JPH0247308Y2 - - Google Patents

Description

[Detailed explanation of the idea]

(Field of Industrial Application) The present invention relates to a lock-up device for a so-called pressurized piston-type torque converter, which is suitable for use in vehicles such as construction machinery where the internal pressure of the torque converter is low during lock-up and the transmitted torque is large. . (Prior art and its problems) In the conventional pressurized piston type lockup device,
A piston that slides under hydraulic pressure and a lock-up damper are arranged between the front cover of the torque converter and the turbine impeller, and the pressure contact force from the piston causes both friction surfaces of the friction plate of the lock-up damper to move on the front cover side. It is designed to be pressed against the friction plate. However, since the support disk that holds the friction plate of the rock-up damper faces the turbine shell of the turbine impeller, a clearance is provided between the support disk and the turbine shell so that the support disk does not interfere with the turbine shell. It is necessary to do so.
Therefore, there is a problem in that the torque converter becomes larger by the clearance. (Object of the invention) The object of the invention is to provide a torque converter lockup device that can eliminate the clearance between the support disk and the turbine shell. (Structure of the invention) (1) Technical means A lock-up damper that elastically connects the front cover of the torque converter and the outer circumference of the turbine hub, and a lock-up damper that elastically connects the front cover of the torque converter and the outer circumference of the turbine hub, and In a lock-up device for a torque converter, the lock-up damper includes a plurality of torsion springs disposed intermittently in the circumferential direction, and a lock-up damper arranged radially inwardly of the clutch to accommodate the torsion springs. an annular support disk having a notch open to the center; and a first support disk disposed on the piston side of the support disk to support the torsion spring together with the support disk on the outer side in the radial direction of the clutch than the flange portion of the turbine hub. A retaining plate and a second plate located on the opposite side of the support disk.
a torsion spring; and a rivet that fixes the inner circumferential edges of both retaining plates to the piston-side outer circumferential surface of the turbine hub in a state where they abut, and the second retaining plate and the torque converter are connected to each other. The inner circumferential edge of the piston is bent toward the inner circumferential side of the torsion spring, and the inner circumferential edge of the front cover is bent along the inner circumferential edge of the piston. This lock-up device for a torque converter is characterized in that the torque converter is bent toward the inner periphery of the torque converter. (2) Function The support disk is sandwiched between both retaining plates, and the retaining plate is integral with the turbine impeller, so no clearance is required between the retaining plate and the turbine shell. (Example) In FIG. 1 showing a case where the present invention is applied to an automatic transmission of a heavy vehicle such as a construction machine, 10 is a four-element two-stage torque converter. A transmission 12 with three forward speeds and one reverse speed is connected to the rear stage of the torque converter 10. The transmission 12 has a first planetary gear 30 that shares one planetary carrier 32.
b, a planetary gear train consisting of a second planetary gear 28b, and a clutch _F3 or brakes _F1 , _F2 , R for controlling the planetary gear train. The transmission 12, the torque converter 10, and a hydraulic gear speed control device, which will be described in detail later, constitute an automatic transmission. The torque converter 10 includes a pump 14, a turbine 16, a fixed stator 18, a reversing stator 20, and a lock-up damper 21 (lock-up clutch).
The structure is such that the power of the engine is transmitted to the engine. Lock-up damper 21 and front cover 2
A piston 21a is slidably provided between the lock-up damper 2 and the piston 21a, and when the piston 21a slides in the direction of the lock-up damper 21 by hydraulic pressure, both surfaces of the lock-up damper become torque transmission surfaces. It's becoming a pattern. The turbine 16 is connected to a turbine shaft 16a,
The reversing stator 20 is connected to a stator shaft 20a. The fixed stator 18 is fixed to the housing 12a by a shaft 18a, and the pump 14 is fixed to the housing 12a by a shaft 18a.
connected to a. A ring gear 14b is provided at the transmission side end of the pump shaft 14a, and the number of teeth of the ring gear 14b is set to _Ze1 . The ring gear 14b is a gear 24b (number of teeth Ze ₂ ) of an intermediate shaft 24a arranged at the upper part of the housing 12a.
The gear 24b is also engaged with the PTO shaft 2.
It meshes with gear 24d of 4c (Power Take Off). A hydraulic pressure source is located at the bottom of the housing 12a. A charging pump 25 is provided, and the charging pump 25 is slid by a sliding gear 25a that meshes with the ring gear 14b. A clutch disk 26a of a clutch _F3 for third speed is fixed in the middle of the turbine shaft 16a. Clutch cover 22b of clutch _F3 is connected to stator shaft 20a. clutch cover 2
A second speed brake F ₂ is arranged outside of the housing 12b, and the brake F ₂ is fixed to the housing 12a. A second sun gear 28 is provided at the end of the stator shaft 20a.
a (number of teeth Za ₂ ) is fixed, and a first sun gear 30a (number of teeth Za ₁ ) is fixed to the end of the turbine shaft 16a. The first sun gear 30a meshes with the first planet gear 30b, and the second sun gear 28a meshes with the second planet gear 28b. A first ring gear 30c (number of teeth Zr ₁ ) is provided outside the first planetary gear 30b.
0c and the first planetary gear 30b are meshed with each other. Further outward of the first ring gear 30c is a housing 1.
A first speed brake F ₁ fixed to 2a is arranged. A second ring gear 28c (number of teeth Zr ₂ ) meshes with the outside of the second planetary gear 28b.
A brake R for reversing is arranged further outward of 8c. Brake R is fixed to housing 12a. As shown in FIG. 2, the first planetary gear 30b and the second planetary gear 28b are held on a carrier 32 in a rotatably engaged state. An output shaft 34 is connected to the carrier 32. The above transmission 12 includes a clutch F ₃ , a brake F ₁ ,
By selectively turning on F ₂ and R, the reduction ratios shown in Table 1 below can be generated. In addition, the ○ mark in the table indicates the ON operation of the clutch and brake.

[Table] Next, details of the lock-up damper 21 disposed between the front cover 22 and the turbine 16 (turbine impeller) will be explained with reference to FIG. In FIG. 3, the turbine 16 is formed from turbine blades 40, a turbine shell 42, a hub 44, and the like. The inner peripheral part of the turbine shell 42 is fixed to the rear surface of the outer peripheral part of the hub 44 with a rivet 46, and the lock-up damper 21, which will be described in detail later, is fastened together with the rivet 46 to the front surface of the outer peripheral part of the hub 44. The inner circumference of the hub 44 is spline-fitted to the front end of the turbine shaft 16a, and the hub 44 is connected to the thrust bearing 44a and the hub 45 of the reversing stator 20.
It is held in a state in which movement in the axial direction is prohibited at the inner circumference front end 45a. A substantially annular piston 21 is provided on the front cover 22.
a is slidably fitted in the axial direction in a fluid-tight manner via O-rings 48, 48a, and an oil chamber 50 is formed between the front cover 22 and the piston 21a. A passage 50a is bored in the center of the front cover 22, and the upper end of the passage 50a in the figure connects to the oil chamber 50 through a space 50b and a gap 50c.
is connected to. Also, the lower end of the passage 50a is a space 5.
It is connected to the passage 16b of the turbine shaft 16a via 0d. The lock-up damper 21 is arranged between the piston 21a and the turbine shell 42. The lockup damper 21 is composed of a first retaining plate 52, a second retaining plate 54, a support disk 56, a torsion spring 58, a friction plate 60, a stop pin 62, and the like. The first retaining plate 52 has a substantially disk shape as shown in FIG. 4, and the first retaining plate 52 has torsion springs 58 (see FIG. 3) at six locations equally spaced in the circumferential direction. A window hole 53 is formed to accommodate the. Also, between the window holes 53, there are stop pins 6 at three locations equally spaced in the circumferential direction.
2 (FIG. 3) is bored through the hole 53a. Furthermore, eight holes 53b, through which the rivets 46 (FIG. 3) pass, are bored at equal intervals in the circumferential direction in the inner circumference of the first retaining plate 52. As shown in FIG. 4a, the first retaining plate 52 has an outer peripheral portion where the window hole 53 and the hole 53a are provided in a substantially L-shape to the left in FIG. 4a (forward in FIG. 3). It's bent. The second retaining plate 54 also has a substantially disk shape as shown in FIG.
a, eight holes 55b are bored at equal intervals in the circumferential direction. As shown in FIG. 5a, the second retaining plate 54 is formed such that the outer peripheral portion where the window hole 55 and the hole 55a are provided is slightly inclined to the left in FIG. 5a. When the inner peripheries of the retaining plates 52 and 54 are brought into contact with each other as shown in FIG. 3, the rivet 46 passes through the holes 53b and 55b.
They are fastened together to the front surface of the hub 44. In this state, the rear surface of the second retaining plate 54 facing the turbine shell 42 extends radially outward along the front surface of the turbine shell 42, and the clearance C between the turbine shell 42 and the second retaining plate 54 is set very little. Note that the clearance C does not necessarily need to be provided by adjusting the dimensions (thickness of the hidden portion) of the stop pin 62, etc.
4 and the turbine shell 42 can also be brought into contact. A support disk 56, which will be described in detail later, is sandwiched between the retaining plates 52 and 54. This support disk 56 is attached to both retaining plates 5 with a stop pin 62 tightening the outer peripheries of both retaining plates 52 and 54.
2 and 54 in the circumferential direction within a predetermined torsional angle range. A notch 57 for accommodating a torsion spring 58 is formed in the inner periphery of the support disk 56, and both ends of the torsion spring 58 are pressed against a circumferential end surface 57a of the notch 57. Also, both ends of the torsion spring 58 are connected to the window holes 5 of both retaining plates 52 and 54.
The retaining plates 52, 54 and the support disk 56 are urged into the initial state by the spring force of the torsion spring 58. The support disk 56 is formed as shown in FIGS. 6 and 6a, with a notch 57 opening inward. Adjacent to this notch 57 is a window hole 5 through which the stop pin 62 (FIG. 3) is inserted loosely, that is, freely rotatable in the circumferential direction.
7b are formed at six locations. A peripheral wall portion 57c is formed on the outer peripheral portion of the support disk 56 and is bent in a substantially L-shape to the left in FIG. 6a, and spline external teeth 57d are formed on the outer peripheral surface of the peripheral wall portion 57c. As shown in FIG. 3, the spline internal teeth 60a of the friction plate 60 are spline-fitted to the spline external teeth 57d. On both friction surfaces 60b and 60c of the friction plate 60, there are two friction plates 6 on the front cover side.
4 are facing each other, and this friction plate 6
4 is a spline inner tooth 22a of the front cover 22
is fitted with a spline. Therefore, the piston 21
When a slides rearward by hydraulic pressure, both wear surfaces 60b and 60c of the friction plate 60 come into pressure contact with the friction plate 64, so that they become torque transmission surfaces during lock-up. The pump 14 of the torque converter 10 is connected to the hub 14
a, and the partition wall 66 of the housing 12
An oil seal 68 is interposed between the hub 14a and the hub 14a. The detailed structure of the hub 14a and the flow path of the hydraulic oil flowing from the charging pump 25 (FIG. 1) through the inside of the torque converter 10 to the passage 16b are described in the utility model registration application filed by the applicant and the PTO-equipped automatic Transmission bearing device (Showa era)
(filed on November 11, 1960). Next, the action will be explained. During lock-up, in which the front cover 22 of the torque converter 10 and the turbine shaft 16 are connected by the lock-up damper 21, pressure oil flows from the passage 16b into the spaces 50d and 50.
b, is supplied to the oil chamber 50 through the gap 50c.
The hydraulic pressure of the pressure oil flowing into the oil chamber 50 is applied to the piston 21a.
When the piston 21a is pushed backward, the friction plate 60 of the lockup damper 21 is pressed against the friction plate 64 on the front cover side by the hydraulic pressure from the piston 21a. At this time, the torque transmitted from the friction plate 64 to the friction plate 60 is transmitted over a wide area of both wear surfaces 60b and 60c, and the torque converter 10 for construction machinery often operates at low rotation speeds and the pressure in the oil chamber 50 is relatively low. However, a large amount of torque is transmitted. As described above, when torque is transmitted from the front cover 22 to the lock-up damper 21, the support disk 56 resists the spring force of the torsion spring 58 and the retaining plates 52, 5
Both retaining plates 52, 54 are attached to the hub 44 by rivets 46.
The turbine 16 and both retaining plates 52 and 54 rotate together. Therefore, the clearance C between the second retaining plate 54 and the turbine shell 42 is larger than that in the conventional case where the support disk 56 faces the turbine shell 16. This eliminates the need to consider interference, making it significantly shorter. Further, since the torsion spring 58 of the lock-up damper 21 is disposed in front of the inner circumferential portion of the turbine shell 42 where the turbine shell 42 is curved rearward, the space inside the torque converter 10 is effectively utilized. When the piston is not locked up, the pressure oil in the oil chamber 50 is discharged through the passages 50a and 16b, contrary to when it flows in, and the piston 21a returns to the front. (Effect of the invention) As explained above, in the torque converter lockup device according to the invention, the turbine shell 4
The support disk 56, which rotates relative to the turbine shell 42, is held between the two retaining plates 52, 54, which do not rotate relative to the second retaining plate 54 and the turbine shell 42. The clearance C between the torque converter 10 and the shell 42 can be made much shorter than before, and the width B (FIG. 3) of the torque converter 10 can be shortened. Although the width B is shortened by about 2 to 3 mm, in the field of the torque converter 10, a slight reduction in size leads to a large cost reduction, and the present invention has a great practical effect. Furthermore, according to the invention, the annular support disk 5 has a recess 57 which is open in the radial direction of the clutch in order to accommodate the torsion spring 58.
6 and a torsion spring 58 disposed on the piston 21a side of the support disk 56 and the hub 44 (turbine hub).
Since the lockup damper 21 is provided with a first retaining plate 52 that supports the clutch on the outer side in the radial direction of the clutch, the dimensions of the lockup damper 21 in the radial direction of the clutch can be made compact, and the torsion spring 58 can be adjusted as much as possible to the clutch radius. It can be held in the outward direction. Therefore, since the length of the torsion spring 58 in the clutch circumferential direction can be set to be long, larger torsional characteristics can be obtained. Moreover, since the inner peripheral edges of the first and second retaining plates 52 and 54 adopted in the present invention are caulked to the turbine hub with rivets 46 while abutting each other, the torsion spring 58 is In combination with the structure, the inner peripheral portion of the lockup damper 21 in the radial direction of the clutch can be made thinner. Therefore, by adopting the present invention, the dimension in the clutch axial direction can be further reduced. Moreover, the inner circumferential edge of the piston 21a of the present invention is bent toward the inner circumferential side of the torsion spring 58, and the inner circumferential edge of the front cover 22 is also bent toward the inner circumferential side of the torsion spring 58.
Since the torsion spring 58 is bent toward the inner circumferential side along the inner circumferential edge of the clutch 1a, the length in the clutch axial direction is shortened even when the front cover 22 is included, contributing to compactness. (Another Embodiment) As shown in the above embodiments, the present invention is applicable not only to FR (front engine, rear wheel drive) type automatic transmissions, but also to FF (front engine, front wheel drive) type automatic transmissions. It can also be applied to transaxles for airplanes and forklifts. In this case, reducing the width B of the torque converter 10 even slightly is more effective in the above-mentioned front-wheel drive vehicles and forklift vehicles where the mounting space for the torque converter 10 is small.

[Brief explanation of the drawing]

Figure 1 is a schematic diagram of the vertical cross-sectional structure of an automatic transmission adopting the present invention, Figure 2 is a cross-sectional view of Figure 1, and Figure 3 is a cross-sectional view of
The figure is an enlarged view of the part in Figure 1, Figure 4 is a rear view of the first retaining plate, and Figure 4a is a--
5 is a front view of the second retaining plate, FIG. 5a is a sectional view taken along a-o-a of FIG. 5, and FIG. 6 is a front view of the support disk.
The figure is a sectional view taken along the line a-a in FIG. 6. DESCRIPTION OF SYMBOLS 10... Torque converter, 16... Turbine, 21... Lock-up damper, 22... Front cover, 21a... Piston, 44... Hub (turbine hub), 46... Rivet, 52...
...first retaining plate, 54...second retaining plate, 56...support disk,
60, 64... Friction plate, 62...
Stop pin.

Claims (1)

[Scope of utility model registration request] A torque converter comprising a lock-up damper that elastically connects a front cover of the torque converter and an outer circumference of a turbine hub, and a piston that connects and disconnects power transmitted between the lock-up damper and the front cover. In the lockup device, the lockup damper includes a plurality of torsion springs disposed intermittently in the circumferential direction, and an annular support disk having a notch that opens inward in the radial direction of the clutch to accommodate the torsion springs. a first retaining plate disposed on the piston side of the support disk and supporting the torsion spring together with the support disk on the radially outward side of the clutch from the flange portion of the turbine hub; and a first retaining plate on the side opposite to the piston of the support disk. the second placed in
a torsion spring; and a rivet that fixes the inner circumferential edges of both retaining plates to the piston-side outer circumferential surface of the turbine hub in a state where they abut, and the second retaining plate and the torque converter are connected to each other. The inner circumferential edge of the piston is bent toward the inner circumferential side of the torsion spring, and the inner circumferential edge of the front cover is bent along the inner circumferential edge of the piston. A lock-up device for a torque converter, characterized in that the torque converter is bent toward the inner circumferential side.