JPH04191552A - Fluid transmission with lockup clutch - Google Patents

Abstract

PURPOSE:To increase the capacity of a lockup clutch without increasing its size by interrupting the inflow of working oil to the outer circumferential side of the disk of the lockup clutch at the time of lockup thereby increasing the effective pressure receiving area of a lockup piston. CONSTITUTION:An annular seal member 34 made of an elastic material of an approximate L cross section is fit at the smaller diameter portion of a step 32 formed along the outermost circumferential portion of a lockup piston 19. The seal member 34 consists of a base portion 36 with a metallic, annular, flat ring 35 embedded in the inner diameter side thereof, and a lip portion 38 extending from the base portion 36 toward outer diameter side thereof and capable of elastic deformation. A front cover 7 is provided with a contact portion 40 having a wall surface capable of coming in the axial direction in contact with the lip portion 38. Along with the increase in the oil pressure in an A chamber, the lip portion 38 elastically deflects to the right, comes in contact with the wall surface of the contact portion 40 of the front cover 7 to prevent working oil from the A chamber to a B chamber. As a result, differential pressure rapidly rises, the lockup piston 19 moves to the right so that the lockup clutch is brought into an engaged condition.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a fluid transmission device with a lock-up clutch used in an automatic transmission of a vehicle or the like.

[Prior art]

It is well known that the 1-lux converter is used in vehicles equipped with automatic transmissions. Its basic configuration is that a turbine runner is placed in a space formed by a pump impeller and a front cover that are integrally connected, with the pump impeller facing each other, and that there is a space between the pump impeller and the turbine runner. The stator is arranged via a one-way clutch. By filling the aforementioned space with oil, a spiral flow of oil generated by the rotation of the pump impeller to which the rotational driving force of the engine is transmitted via the front cover acts on the turbine runner, causing the turbine runner to rotate. If the ratio of the rotational speeds of the pump impeller and the turbine runner is below a predetermined clutch point, the direction of the oil flow is changed by the stake, so the torque is amplified and transmitted to the turbine runner. Moreover, when the clutch point is exceeded, rotation is transmitted accompanied by torque amplification.

However, in the case of a torque converter like this, there is always a rotation between the pump impeller and the turbine launch! ? This difference in number causes a loss in torque transmission.

Therefore, recently, in order to improve the fuel efficiency of vehicles, 1-
A fluid transmission device with a cock-up clutch has been developed and is in use, which is equipped with a lock-up device that mechanically directly connects the front cover, which is the input element, and the hinge runner, which is the output element, of the converter converter. Its general configuration will be explained as follows.

FIG. 5 is described in Japanese Unexamined Patent Publication No. 57-18853, and the reference numeral 1 indicates a torque concha.

A pump impeller 2 forming a part of the torque converter 1 has a configuration in which a large number of pump blades 4 are attached to the inner surface of an annular bowl-shaped outer shell 3. outer shell 3
The outer periphery of is integrally connected to the bottomed bowl-shaped front cover ■ by welding.

The front cover 7 is attached to the drive plates 1 and 5 which are rotatably connected to the engine crankshafts 1 to 1 (not shown) serving as the human power shafts of the torque converter 1 by means of portolo. Further, an extension sleeve 8 is attached to the inner peripheral portion of the outer shell 3, and a hydraulic pump 9 is rotationally driven through this extension sleeve 8.

In the space formed by the pump impeller 2 and the front cover 7, a turbine runner O is arranged facing the pump impeller 2 and on the same axis, and like the pump impeller, a large number of turbines are arranged in an annular bowl-shaped outer shell 11. It has a configuration in which a blade 12 is attached. The inner peripheral side of the outer shell 11 is attached to a turbine hub 14, and the turbine hub 14 is further attached to an input shaft 13 of an automatic transmission as an output shaft of the torque converter 1 by splice fitting.

A stake 15 is disposed between the pump impeller 2 and the inner periphery of the turbine runner 0, and the stator 15 is engaged with a stator shaft 17 via a one-way clutch 16 disposed on the inner periphery of the stake 15. ing.

A seal ring 18 is provided on the outer peripheral side of the turbine hub 14.
A lock-up piston 19, which is an annular plate, is fitted so as to be movable in the axial direction of the input shaft 13 while maintaining liquid tightness. On the surface facing the inner surface (the space side) of the front cover 7 of the one-piece pickup piston 19, on the inner circumference side from the outermost circumference of the lock amplifier piston, there are further the drive plays 1 and 5 and the front cover 7. A lock-up clutch disk 20, which is a friction lug, is installed at the same radial position as the ports 1 to 6 that connect the two.

Further, the turbine hub 14 includes a turbine plate 2.
1 is fixed, and this turbine plate 21 is connected to the outer periphery of the lock-up screws 1 to 19 via a damper mechanism 22 provided on the outer periphery of the turbine plate 21.

Therefore, in the torque converter with a lock amplifier clutch configured as described above, the spiral flow generated by the rotation of the pump impeller 2 acts on the turbine runner 10. As a result, the turbine run 10 rotates and the input shaft 13
Power is transmitted to an automatic transmission (not shown) via.

The oil passage (on-circuit) 23 between the stator shaft 17 and the extension sleeve 8 is operated into the space formed by the back side of the lock-up screw 1 19 and the pump impeller 2, that is, the A chamber in FIG. Oil passage that supplies oil and passes through the input shaft 13 at the same time (off circuit)
24 and from the space formed by the front side of the lock-up piston 19 and the front cover 7, that is, the illustrated chamber B, a pressure difference is generated between chambers A and B.
The lock-up piston 19 receives this pressure and is pushed to the right in the figure. As a result, the lock-up clutch disc 20 comes into frictional contact with the front cover 7, and the lock-up device is brought into a locked state.
and the turbine runner 10 are in a directly connected state. When the lock-up clutch is released, hydraulic oil is supplied to the B chamber from the off circuit 24, and the on circuit 24 communicates with the chamber.
By discharging from 3, B
The oil pressure on the inner circumferential side of the lock-up clutch 20 in the room increases, and the lock-up piston 19 is pressed in the release direction (left side in the figure), and the open/close-up clutch disc 20 is separated from the front cover 7. The lockup will be released.

As is clear from the above explanation, the lock-up clutch disc 20 is pressed against the front cover 7 and transmits torque by generating frictional force, but at the same time it also has the sealing function between the A chamber and the B chamber. will have.

[Problem to be solved by the invention]

The lock-up clutch disk 20 generally functions by being compressed between portions that are formed flat and parallel to each other.

However, in the above configuration, in the pressing process when forming the front cover 7, the corners 30 of the front cover 7 are formed in a predetermined R shape in most cases due to strength or raw material. The outer circumferential portion of the lock amplifier piston 19 is also formed in an R shape corresponding to the R shape of the front cover 7.Therefore, the lock up clutch disc 20 has an R shape corresponding to the R shape of the lock up piston 19. It is attached to a flat portion disposed substantially parallel to and facing the front cover 7 on the inner circumferential side.

Therefore, when the lock-up clutch is engaged, the hydraulic oil in the A chamber enters into the outer circumferential side of the lock amplifier clutch disc 20.

Therefore, if the lock-up piston 19 receives a pressing force F in the engagement direction (rightward in the figure), the lock-up piston 19
It is determined by the area S that receives the pressure P of the chamber A (
, F = P
The pressing force in the engagement direction that is applied to the shaft is offset by the hydraulic pressure that has entered as described above. Therefore, the actual pressing force applied to the lock amplifier clutch disc 20 is F=PX (S-3'').

As described above, in the conventional structure, since the effective pressure-receiving area of the lock-up piston 19 is small, there is a problem in that a large latch capacity cannot be obtained.

Therefore, the present invention has been made in view of the problems of the prior art, and an object to be solved by the present invention is to prevent the lock-up clutch from being locked when the lock-up clutch is engaged, without increasing the size of the torque converter device. By preventing hydraulic oil from entering the up-clutch disc side, the effective pressure receiving area of the lock-up clutch is expanded and the clutch capacity of the lock-up clutch is increased.

[Means to solve the problem]

In order to solve the above-mentioned problems, the present invention takes the following measures.

A bottomed bowl-shaped front cover connected to an input shaft rotationally driven by the driving force of the engine, a pump impeller that rotates integrally with the front cover, and a pump impeller in the space formed by the front cover and the pump impeller. a turbine runner, which is arranged opposite to the turbine runner and whose inner circumferential portion is rotationally connected to the output shaft; The lock-up screws 1 to 7 are movable in the direction, and the lock-up screws 1 to 7 are located on the inner circumferential side in the radial direction from the outermost periphery of the long-quad piston, and are connected to the space side wall surface of the front 1-cover. being squeezed by hydraulic pressure generated in the space between
A lock-up clutch disc that rotationally connects the front cover and the turbine runner, the lock-up clutch disc being disposed between the outermost circumference of the lock amplifier piston and the front cover, and disposed in the axial direction of the output shaft. a base that is attached to either the lock-up piston or the fluorocarbon runner in a state where movement in a direction opposite to the turbine runner is prevented; and a base that extends in the radial direction integrally with the base. a sealing member having a lip portion;

The sealing member includes an abutting portion provided on the other side of the lockup piston or the front knee cover and abutting against the lip portion of the sealing member when at least the lockup piston and the frontier disk are in a rotationally connected state.

[Function] In the present invention, the sealing member disposed between the outermost periphery of the lock-up piston and the front cover prevents hydraulic oil from entering the outer periphery of the long-quare and pu-crunch discs during lock-up engagement. Therefore, the pressure is lower in the outer circumferential portion of the lock amplifier clutch disk between the lock-up screws I and the front cover than on the rear side (bumper side) of the CL knock-up screws 1 to 1. As a result, the effective pressure receiving area of the lockup piston increases.

〔Example〕

Embodiments of the present invention will be described below based on the drawings shown in FIGS. 1 to 4. The present invention can be realized by partially improving the prior art described above, so the configuration other than the improved part is the same as that of the prior art, and the explanation of the configuration will be omitted and the main parts related to the present invention will be omitted. The explanation will be given using an enlarged sectional view.

FIG. 1 shows a first embodiment of the present invention.

A step 32 is formed in the outermost periphery of the lock-up piston 19 in the radial direction (in the vertical direction in the figure), and a small diameter portion of the step 32 is formed with an I1-shaped cross-sectional path made of an elastic material such as a rubber material. An annular sealing member 34 is fitted therein.

The sealing member 34 includes a base portion 36 having a metal annular flat plate link 35 on the inner diameter side, and a lip portion 38 that extends from the base portion 36 toward the outer diameter side and is elastically deformable in the horizontal direction in the drawing. It is configured.

In addition, in order to prevent the lip portion 38 from collapsing more than a predetermined amount in the axial direction of the input shaft 13 to the side opposite to the Tahin runner, and to exhibit a sealing function, the fluorocarbon 1 hekahar 7 is connected to the lip portion 38 in the axial direction (left and right in the figure). A contact portion 40 having a contactable wall surface is formed.

The lock-up clutch disc 20 that is attached to the lock amplifier screw 1-19 is the first one.
As shown in Fig. 9-4, slits 42 are formed at five locations in the circumferential direction, and function as oil passages that communicate the inner and outer peripheral portions of the rotor-up clutch disc 20 when the lock-up clutch is engaged.

In the torque converter 1 configured as described above, when hydraulic oil is supplied from the on-circuit 23 in FIG. is pressed to the right in the figure.

When the oil pressure difference between chamber A and chamber B is small, the lip portion 3
8 and the front cover 7, the lip portion 38 elastically deforms in the right direction in the figure as the oil pressure in the chamber A increases, causing the gap formed on the front cover 7 to move. By coming into contact with the wall surface of the contact portion 40 and the axis (in the left-right direction in the figure), hydraulic oil is prevented from entering from the A chamber and the B chamber. In addition, the hydraulic oil before being blocked is
Since it flows to the inner circumference side from the slit 42 of the lock-up clutch disc 20 and is output from the off circuit 24, the lock-up clutch disc 1 is inside the B chamber.
A low pressure state occurs at the inner and outer peripheral portions of the chamber 9, and the differential pressure between chambers A and B rapidly increases.

As a result, the lock-up piston 19 quickly moves to the right in the drawing, and the lock-up clutch disc 20 is pressed against the front cover 7 and comes into frictional contact, so that the lock-up clutch comes to a stopped state. In this way, the engagement operation is shortened, and even when the lock-up clutch is engaged, the outer circumferential side of the lock-amp clutch disc 20 is also maintained at a low pressure state by the seal member 34, so that the lock-up piston 19 The force (retaining force) that presses the lock-up clutch disc 20 against the front cover 7 increases as the effective pressure-receiving area of the lock-up piston 19 is expanded, and the clutch capacity of the lock-up clutch increases. .

In addition, hydraulic oil is supplied from the off circuit 24 communicating with the B chamber and discharged from the on circuit 23 communicating with the A chamber, so that the inside of the B chamber is connected to the inner peripheral side of the lock-up clutch disc 20 and through the slit 42. The outer peripheral side is also in the same high pressure state, and the entire front side (right side in the figure) of the lock-up piston 19 receives the differential pressure with the chamber A, which is in a low pressure state.

Note that when a pressure difference of more than a predetermined value occurs, the lip portion 38 of the sealing member 34 is elastically deformed to the left side in the figure, causing the separation between chambers B and A.
The chambers are in a communicating state, and in the initial state of communication, the communicating portion has a throttling function that regulates the flow of hydraulic oil from the B chamber to the A chamber.

Since the differential pressure between chambers A and B is sufficiently maintained by the above throttling function, the lock-up piston 19 smoothly moves to the left in the figure, and the lock-up clutch disc 20 moves to the lock-up position spaced apart from the front cover 7. The state is released.

FIG. 2 shows a second embodiment of the present invention.

A step 32 is formed at the outermost circumference of the lock amplifier piston 19, as in the first embodiment, and an annular sealing member 44 formed in the shape of a broken circuit is attached to the small diameter portion of the step 32.
2, it is fitted on the engine side (right side in the figure) while its movement is restricted.

The seal member 44 includes a base portion 36 that contacts the outermost circumferential surface of the lock-up piston 19 and a lip portion 38 that extends toward the outer circumferential side in the radial direction.
A metal ring 46 having an annular cross-shaped shape that substantially coincides with that is embedded therein, and prevents the lip portion 38 from falling down in the left-right direction in the drawing, and also allows the base portion to be locked up by elastic force in the radial direction. It is crimped onto the piston 19.

Furthermore, a groove 48 is formed in the inner circumferential portion of the front cover 7 at the portion where the seal member 44 is fitted, and the front cover 7 and the pump impeller 2 are connected by ensuring a contact area between the welded portion. It functions as a bypass passage that communicates chamber A and chamber B when the lock-up clutch is released while preventing a decrease in the strength of the torque converter, thereby preventing a decrease in the circulation of hydraulic oil within the torque converter. Furthermore, the lip portion 3 is located on the engine side (right side in the figure) of the groove portion 48.
A contact portion 50 is formed that can come into contact with 8 in the axial direction (left and right in the drawing). The lock-up clutch disk attached to the lock-up piston 19 is provided with slits 1 to 42 as in the first embodiment.

The operation and effect different from the first embodiment is that the lip portion 38 of the sealing member 44 hardly allows elastic deformation in the axial direction, so that the sealing point is fixed to the lock-up piston 1.
The seal member 44 does not perform its sealing function until the lock-up clutch is almost at a standstill, as determined by the axial movement of the lock-up clutch 9. However, during the lock-up screw, the seal member 44 Since the lip portion of the lock-up piston 19 is not easily deformed, the oil pressure inside the chamber B can be effectively increased, and the lock-up piston 19 can quickly start moving.

FIG. 3 shows a third embodiment of the present invention.

As in the second embodiment, a seal member 52 is fitted into the small diameter portion of the outermost circumference of the lockup piston 19. The outer periphery of the lip portion 38 of the sealing member 52 is formed in a tapered shape, and correspondingly, a tapered contact portion 54 is also provided on the inner periphery of the fluorocarbon 1-cover 7. Note that the same actions and effects as in the second embodiment can be obtained.

Although the specific embodiment illustrated has been described above,
The present invention is not limited to these embodiments, and various other embodiments are possible within the scope of the present invention.

For example, in the first to third embodiments, the seal member was attached to the lock amplifier piston, and the abutting part that abuts the limp part was formed on the front cover.
A similar effect can also be obtained vice versa.

In addition, the lock-up clutch disk attached to the lock-up screw 1 was provided with 5 slots in the circumferential direction, but the number of slots was determined arbitrarily, and even if there were no slits, the lock-up clutch disc could not be engaged. At this time, the hydraulic oil that has entered the outer periphery is gradually discharged toward the inner periphery of the lock-up clutch disk surface by the pressure generated on the inner and outer peripheries of the lock-up clutch disk.

〔effect〕

In the present invention, since the effective pressure receiving area of the lock 7/knob piston is expanded, it is possible to amplify the clutch capacity when the lock-up clutch is engaged.

In addition, since the clutch capacity is amplified as described in 1., when the same clutch capacity as before is required, it is possible to reduce the hydraulic pressure generated in the torque converter, and the front cover, pump impeller, etc. In addition to suppressing the deformation of parts due to hydraulic pressure and improving the durability of the torque converter, it also reduces the uneven contact of the single-piece pull-up clutch disk due to such deformation, improving the durability of the lock amplifier clutch disk.

[Brief Description of the Drawings] Figures 1 to 3 are drawings of each embodiment in which the present invention is applied to the prior art shown in Figure 5, and Figure 1 shows the main parts of the first embodiment. FIG. 2 is an enlarged sectional view of the main part of the second embodiment, and FIG. 3 is an enlarged sectional view of the main part of the third embodiment. FIG. 4 shows a front view of the lock-up piston used in the first to third embodiments with the lock-up clutch disk removed. FIG. 5 shows a side sectional view of a conventional torque converter with a lock amplifier. Explanation of symbols 1 - Torque converter 2 - Pump impeller 5 - Drive plate 1 - 6 - Bolt 7 Front cover 10 Hinge runner 19 Lock amplifier piston 20 Lock up clutch disc 32 - Step 34, 44, 52 Seal member 35 Ring 36 Base 38 Limp part 40.50.54 Contact part ＼ □□-77 □---1 N/ / / ＼ ＼ ＼ Figure 3 52 Seal @β Half-yearly contact μ ／-1-＼ , ノ' ／ ／ N■■（

Claims (1)

[Claims] A front cover is formed by a bottomed bowl-shaped front cover connected to an input shaft rotationally driven by the driving force of the engine, a pump impeller that rotates integrally with the front cover, and the front cover and the pump impeller. a turbine runner disposed in a space facing the pump impeller and having an inner peripheral portion rotationally connected to the output shaft; and a turbine runner disposed facing a side wall surface of the space of the front cover and rotationally connected to the turbine runner. a lockup piston that is movable in the axial direction of the input shaft; and a lockup piston that is located radially inward from the outermost circumference of the lockup piston, and that is connected to a side wall surface of the space between the lockup piston and the front cover. In a fluid transmission device with a lockup clutch, the lockup clutch disc includes a lockup clutch disc that is compressed by hydraulic pressure generated in the space between the two and rotatably connects the front cover and the turbine runner, the outermost periphery of the lockup piston a base that is disposed between the lock-up piston and the front cover, and is attached to either the lock-up piston or the front cover in a state where movement in a direction opposite to the turbine runner in the axial direction of the output shaft is prevented; a sealing member having a lip portion integrally formed with the base portion and extending in the radial direction; and provided on the other side of the lockup piston or the front cover, when at least the lockup disk is in a rotationally connected state. A fluid transmission device with a lock-up clutch, comprising: a contact portion that contacts a lip portion of the seal member.