JPH03181620A - Clutch hydraulic pressure controller for automatic transmission - Google Patents

Abstract

PURPOSE:To obtain an automatic transmission of remarkably small size and light weight by constituting the device so that relative rotating members are relatively rotated by a prescribed quantity due to relative torque between the input side and the output side members to change the opening area of a variable opening part for draining clutch liquid pressure. CONSTITUTION:It is instituted that the opening area of a variable opening part 62 becomes large for communication on the rotated position of relative rotating members 52 at generating negative torque. Hereby, even in the case of feeding pressure liquid a little earlier to a clutch L/C, the pressure liquid is drained from the variable opening part 62. Therefore, engagement of the clutch L/C in the condition of generating negative torque can be prevented. Meanwhile, when the torque output to an output shaft 10 is changed over positive, the relative rotating members 52 are reversely rotated to make smaller or shut off the opening area of the variable opening part 62, hereby, the clutch liquid pressure is raised to engage the clutch L/C.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a control device for hydraulic pressure supplied to a gear shifting clutch of an automatic transmission.

Conventional automatic transmissions installed in vehicles include, for example, the Japanese Patent Application Laid-Open No. 6
(There is one disclosed in Publication No. 184441.

As shown in Fig. 5, a gear train is constructed from two planetary gear sets PG, PC, (front and rear), and the gear train includes a plurality of hydraulically operated friction elements (
Reverse clutch R/C, high clutch H/C.

Low clutch L/C, ROHM reverse brake L&R/
B.

A band brake B/B) is incorporated, and these friction elements are engaged and released as appropriate, so that each I! ! The coupling relationship of the elements constituting the star gear sets PC+ and PG* is changed, thereby changing the gear ratio, that is, changing the speed.

By the way, the hydraulic pressure supplied to the friction element is switched by a hydraulic valve (not shown), and the timing for supplying and removing the hydraulic pressure is determined.

In the figure, 1 is an input shaft, and 2 is an output shaft.

Problems to be Solved by the Invention However, in such conventional automatic transmissions, the timing of engagement and release of the friction elements is determined during gear shifting as described above, but this timing is controlled by the engagement hydraulic pressure. This is extremely difficult because it involves various changing factors such as line pressure, which determines the timing, and oil temperature, which affects viscosity. If even the slightest deviation occurs in the timing, torque will be pulled, and the gear shift system will be affected. 3γ error is generated.

For example, the automatic transmission disclosed in the above-mentioned publication has a shifting function of 4 forward speeds and 1 reverse speed, and when downshifting from 4th speed to 3rd speed while driving, the band brake H/B is released and New low clutch 1. /C is designed to be engaged, but at this time, the above-mentioned low clutch L/C is
It is conceivable that the band brake R/R is engaged when the gear train is in a state where it can idle and the engine rotation speed is increased to a rotation speed corresponding to the increase in gear ratio due to downshift. If the low clutch L/C is engaged even a little earlier than this, the engine speed has not yet reached the point corresponding to 3rd gear, so 1=
Negative torque is generated in the output shaft 2 of the single dynamic transmission, and a large shift shock is generated.

For this reason, in the past, a one-way clutch OfC was provided between the low clutch drum 3 as the output side member of the rotary notch L/C and the transmission case 4, and even when torque was pulled, the low clutch drum 3
By preventing the low clutch L from being reversed,
/C can be engaged smoothly, thereby reducing shift shock.

Therefore, since the one-way clutch OWC is incorporated into the gear train, there are problems in that the automatic transmission is forced to be larger and its weight is significantly increased.

Therefore, the present invention focuses on the fact that the input side member and the output side member of the clutch are relatively rotated in opposite directions when torque is pulled in, and utilizes this relative rotation direction to rotate the clutch. It is an object of the present invention to provide a clutch hydraulic pressure control device for a variable transmission that makes it possible to eliminate a one-way clutch by timing the supply of hydraulic pressure and controlling the timing of engagement of the clutch.

Means for Solving the Problems To achieve the object, the present invention provides an automatic transmission equipped with a clutch that is incorporated in a gear train and that is engaged or released by supplying or removing hydraulic pressure to switch gear ratios. , A relative rotational member capable of relative rotation by a predetermined amount to the input side member or output side member of the clutch is provided, and the relative rotational force between the input side member and the output side member is extracted and applied to the relative rotational member. A relative rotational force extraction member for transmission is provided, and a variable opening whose opening area is changed depending on the relative rotational position of the two is provided between the relative rotational member and the input side member or the output side member, The clutch hydraulic pressure is drained through the variable opening.

In the clutch hydraulic pressure control device for an automatic transmission of the present invention having the above-described structure, the rotational force generated during relative rotation between the input side member and the output side member of the clutch is transmitted through the relative rotational force extraction member. The relative rotational direction of the input side member and the output side member is transmitted to the relative rotational member.
In other words, the automatic throat shaft is rotated within a predetermined amount according to the positive and negative torques generated in the outer throat shaft, thereby changing the opening area of the variable opening.

Therefore, by setting the opening area of the variable opening to be large in communication at the position where the relative rotation member is rotated when the negative torque is generated, it is possible to Since the clutch hydraulic pressure is drained from the variable opening, it is possible to prevent the clutch from being engaged in a negative torque generation state.

On the other hand, when the torque output to the output shaft switches to positive, the relative rotation member is reversed and the opening area of the variable opening changes to a small value or is shut off, so the clutch fluid pressure rises. The clutch is then engaged.

Example Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

That is, FIGS. 1 to 3 show a hydraulic pressure control device for a variable transmission according to an embodiment of the present invention. FIG. 1 shows the main parts of a gear train, IO is an input shaft, and 12 is an output shaft. The abutting ends of the input shaft IO and the output shaft 12 are coaxially fitted and supported relative to each other by a coaxial shaft Ij.

Spline 14 is on the outer periphery of the input shaft IO.
A rear sun gear S11 is fitted through the rear sun gear Sll, and a rear pinion gear PIl is meshed with the rear sun gear Sll, and a rear internal gear 6 is meshed further outside the rear pinion gear pH.
．． Rear binion gear PR and rear internal gear I
R constitutes the rear side free play Jl', m car set pc.

Further, the rear planet carrier PCR connected to the rear pinion gear PR is connected to the output shaft 1.
2 through a spline 16, and the output rotation of the gear train is output from the rear planet carrier PC1l to the output shaft 12.

In addition, on the right side of the diagram of the planetary gear set PC on the rear side,
Although not shown, a planetary gear set on the front side is arranged,
The front internal gear of the front planetary gear set is connected to the rear planet carrier PC6l, and the front planet carrier of the front planetary gear set is connected to the low clutch driver 18.

Incidentally, a clutch plate 20 of the low clutch L/C configured as a wet multi-disc clutch is provided between the inner periphery of the low clutch drum 18 and the outer periphery of the rear internal gear I6. The low clutch L/C is engaged by pressing with the clutch piston 22, and in this embodiment, as disclosed in Japanese Patent Application Laid-Open No. 60-84441, the low clutch L/C is engaged at the first forward gear. This is done in 1st, 2nd, and 3rd gears.

Here, the clutch plate 20 includes a plurality of drive plates 20a that are spline-fitted to the rear internal gear Im as an input end member, and a plurality of drive plates 20a that are spline-fitted to the low clutch drum 18 as an output side member. The drive plate 20a and the driven plate 20b are arranged to overlap alternately.

On the other hand, the low clutch drum 18 extends in a direction opposite to the front planetary gear set (to the left in the figure) to form a storage chamber 24 for the clutch piston 22.

The storage chamber 24 is formed into an annular shape with an inverted U-shaped cross section, consisting of an inner cylinder part 24a, an outer cylinder part 24b, and a bottom part 24c, and is slidable with a liquid-tight structure between the inner and outer cylinder parts 24a and 24b. A piston chamber 24d is configured between the fitted L-shaped latch piston 22 and the bottom portion 24C, and
The inner cylindrical portion 24a is rotatably fitted onto the outer periphery of a cylindrical portion 26a formed integrally with the transmission case 26.

Further, a supply passage 28 for clutch extraction pressure is formed in the thick part of the cylindrical part 26a, and an annular groove 30 communicating with the supply passage 28 is formed in the outer periphery of the cylindrical part 26a. A radial through hole 32 formed in the inner cylinder portion 24a
The annular groove 30 and the piston chamber 24d communicate with each other through the annular groove 30 and the piston chamber 24d.

By the way, a plate 34 is integrally fixed to the rear internal gear Isl, and the rear internal gear 1 m
is rotatably supported on the outer periphery of the spline 16 fitting portion of the rear planet carrier Pct via the plate 34, and one side of the plate 34 and the tip of the inner cylindrical portion 24a are in contact with each other. Being faced with.

Here, in this embodiment, a small diameter part 50 is formed on the outer periphery of the tip of the inner cylinder part 24a, and an orifice switching ring 52 as a relative rotation member is fitted into the small diameter part 50 so as to be relatively rotatable. .

On one side 52a of the orifice switching ring 52, a third
As shown in the figure, a concave portion 54 is formed, and the inner cylinder portion 24a has a width W smaller than the circumferential direction 1w+ of the four portions 54.
A convex portion 56 is formed that protrudes with , and the convex portion 56
is fitted into the recess 54, so that the orifice switching ring 52 and the inner cylinder part 24a have a predetermined fit (w, -
Relative rotation by w, ) is possible.

Also, within the wall thickness of W4m248 above, there is a piston chamber 2.
A drain passage 58 is formed in the orifice switching ring 52, and the orifice switching ring 52 is formed so that the orifice switching ring 52 is inserted into the inner cylindrical part 24a in the middle of FIG. The switching passage 6 communicates with the drain passage 58 when the switching passage 6 is relatively rotated in the direction and stopped.
0 is formed.

Incidentally, when the orifice switching ring 52 rotates relative to the direction B in FIG. 3, the switching passage 60 moves to the position indicated by the broken line and is cut off from the drain passage 58.

A variable opening 62 is formed by the second drain passage 58 and the switching passage 60.

By the way, the orifice switching ring 52 has a relative fit.
The A direction in which the motor is rotated is when there is a torque pull-in.
A state is reached in which reverse torque is input from the output shaft 12 to the gear train.

On the other hand, in the B direction, the engine is in a normal driving state, and the driving force is transmitted from the input shaft IO to the gear train.

Between the orifice switching ring 52 and the plate 34, a bearing 64 is provided as a relative co-rotating force extraction member.
is disposed, and the relative rotation difference generated between the plate 34 and the inner part 24a is generated as a frictional force in the bearing 64, and this frictional force causes the orifice switching ring 52 to move against the plate 34. They are now being carried around.

With the above configuration, in this embodiment, the vehicle is running in any one of the first to third speeds, and the low clutch 1. /C is in the fastened state, the engine driving force is transmitted from the input shaft lO to the output shaft 12, so the orifice switching ring 52 is in state B in FIG. 3, and the drain passage 58 and the switching passage 60 are in a state of being cut off from each other.

Therefore, in this state, the supply passage 28. The clutch Aft pressure supplied to the piston chamber 24d via the annular groove 30 and the through hole 32 is maintained at a predetermined pressure, and the clutch plate 20 is engaged via the clutch piston 22 pressed by the clutch extraction pressure. The condition continues.

Here, when downshifting from 4th gear to 3rd gear is counted as 4, in this case, the band brake (not shown) that is in the engaged state is released, and the low clutch [, /C, which is in the released state] is engaged. However, the engagement of the low clutch L/C is performed by introducing clutch oil pressure into the piston chamber 24d as described above, and a time chart showing the operating state at this time is shown in FIG. .

That is, during such a downshift, as shown in FIG. 4(d), after the band brake engagement hydraulic pressure (4th speed band brake Ab pressure) is removed, the low clutch L/C
When the band brake is released, the gear train temporarily becomes idle, and reverse torque is introduced from the output shaft 12.

Therefore, at this time, the orifice switching ring 52 is
Since the state is relatively rotated in the direction of entry in FIG. 3, and the drain passage 58 and the switching passage 60 are in communication with each other,
When the clutch oil pressure is supplied to the piston chamber 24d early, the clutch oil pressure is drained through the drain passage 58 and the switching passage 60, as shown in FIG. 4(d).

Therefore, the oil pressure in the piston chamber 52 is suppressed to a low level as shown in FIG. 5(e), and it is possible to prevent the low clutch L/C from being engaged.

In this way, when the reverse torque is applied manually, engagement of the low clutch L/C is reliably prevented, as shown in (f) in the same figure.
As shown in FIG. 2, no torque is drawn (indicated by the broken line), and therefore, shift shock can be prevented.

Next, with the gear train idling, when the engine rotation speed is increased to the same rotation speed corresponding to the gear ratio of the 3rd gear to be downshifted, from then on, the engine torque is transferred from the input shaft 10 to the gear train by human power. It will be in a state where it is

Therefore, the orifice switching ring 52 is relatively rotated in the direction B in FIG. 1-kari (Fig. 4(d))
), low clutch 1. /C is concluded.

Therefore, in this embodiment, low clutch 1. /C conclusion and
Synchronization with the predetermined engine speed, that is, low clutch 1. /C person, rotation synchronization of output side member (Figure 4 (a))
However, since this is performed by controlling the clutch extraction pressure by the variable amount LI section 62, it becomes possible to eliminate the conventional one-way clutch, and it becomes possible to achieve a reduction in size and weight of the r1 dynamic transmission.

It is also possible to control the clutch oil pressure by using a solenoid valve after detecting the direction of human torque applied to the gear train using a sensor, but if an electric signal is used in this way, the reliability will be significantly reduced. , may cause malfunction.

By the way, although this embodiment has been explained by taking the low clutch L/C as an example, it is not limited to this, and other clutches, for example, the automatic transmission disclosed in Japanese Patent Application Laid-Open No. 62-62047, can be similarly applied. Low and reverse brakes that require synchronous control are used, so it goes without saying that the present invention can be applied to latches that require synchronous control.

Further, in this embodiment, the orifice switching ring 52 is provided on the inner cylinder portion 24a of the low clutch drum 18 which is the output side member, but the orifice switching ring is provided on the input end member side. It is also possible to relatively rotate the orifice switching ring using the relative rotational force between the input side member and the output side member, and in this case, by reversing the opening/closing relationship between the drain passage and the switching passage,
” It is possible to exhibit the same function as in the second embodiment.

As described in detail, the clutch hydraulic pressure control device for an automatic transmission of the present invention includes a relative rotation member capable of relative rotation by a predetermined amount relative to the input side member or the output side member of the clutch. The relative rotation member is provided with a person.

The opening area of the variable opening that drains the clutch hydraulic pressure is changed by causing relative rotation by a predetermined amount using the relative rotational force between the output side members, so that the synchronization between the clutch engagement point and the input rotation can be maintained. This can now be done easily without the use of a one-way clutch, making it an intimidating small light vehicle with an automatic transmission! It has the excellent effect of being able to achieve a

[Brief explanation of drawings]

Fig. 1 is a sectional view of a main part showing an embodiment of the present invention, the second bacterium is an enlarged sectional view of a main part of an embodiment of the invention, and Fig. 3 is an explanation showing the operating state of an embodiment of the invention. FIG. 4 is a time chart showing the operating state of the present invention, and FIG. 5 is a schematic configuration diagram of an automatic transmission using a conventional clutch hydraulic pressure control device. DESCRIPTION OF SYMBOLS 10... Input shaft, 12... Output shaft, 18... Low clutch drum (output side member), 52... Orifice switching ring (relative rotation member), 58... Drain passage, 60...・Switching passage, 62
...Variable opening, 64...Bearing (relative rotational force extraction member), L/C...Low clutch, 11...
Rear internal gear (input end member). Figure 2

Claims (1)

[Claims] (1) In an automatic transmission equipped with a clutch that is incorporated in a gear train and is engaged or released to switch gear ratios by supplying or removing hydraulic pressure, a position is applied to the input side member or output side member of the clutch. A relative rotation member capable of relative rotation by a fixed amount is provided, and a relative rotation force extraction member is provided that extracts the relative rotation force between the input side member and the output side member and transmits it to the relative rotation member, and A variable opening is provided between the member and the input-side member or the output-side member, the opening area of which is changed according to the relative rotational position of the two, and the clutch hydraulic pressure is drained through the variable opening. Features a clutch hydraulic control device for automatic transmissions.