JP2005265020A - Hydraulic power transmission - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hydraulic power transmission whose size is easily reduced while securing sufficient torque capacity. <P>SOLUTION: A torque converter 1 can transmit power from a front cover 2 to a turbine hub 5. The torque converter 1 comprises: a pump impeller 3 attached to the front cover 2; a turbine runner 4 attached to the turbine hub 5 to face the pump impeller 3; and a stator 6 for guiding fluid flowing from the turbine runner 4 to the pump impeller 3. When a torus which is formed of the pump impeller 3, turbine runner 4 and stator 6 is divided by a predetermined reference plane RS perpendicular to an axial direction of the turbine hub 5, a blade 3b of the pump impeller 3 is positioned to one side of the reference plane RS and a blade 4b of the turbine runner 4 and the blade 6b of the stator 6 are positioned to the other side of the reference plane RS. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a fluid transmission device that transmits power from an input member to an output member via a fluid transmission element.

  Conventionally, a torque converter (fluid transmission device) having a pump impeller and a turbine runner facing each other and a stator disposed therebetween is known (see, for example, Patent Documents 1 and 2). Also, as this type of torque converter, one having a stator including a blade having an overhang portion extending toward the pump impeller along the pump shell and an overhang portion extending toward the pump impeller along the turbine shell is known. (For example, see Patent Document 3). In the torque converter configured in this way, it is possible to suppress the occurrence of fluid vortices between the turbine runner and the stator or between the stator and the pump impeller, so that the pump impeller, the turbine runner, and the stator The rectifying property of the fluid circulating through can be improved.

Japanese Utility Model Publication No. 5-022917 JP-A-7-332461 Japanese Utility Model Publication No. 3-035359

  Incidentally, in recent years, there has been a demand for further downsizing the torque converter as described above. However, if the conventional torque converter as described above is reduced in size (flattened) as it is, the torque capacity is reduced.

  Accordingly, an object of the present invention is to provide a fluid transmission device that can be easily downsized while sufficiently securing a torque capacity.

  The fluid transmission device according to the present invention is a fluid transmission device that transmits power from an input member to an output member, a pump impeller attached to the input member, a turbine runner attached to the output member and facing the pump impeller, and a turbine A stator for guiding the fluid flowing out from the runner to the pump impeller, and a torus formed by the pump impeller, the turbine runner, and the stator is divided by a predetermined reference plane perpendicular to the axial direction of the output member. The blades of the pump impeller are located on one side of the surface, and the blades of the turbine runner and the stator are located on the other side of the reference surface.

  When the torus (annular flow path) formed by the pump impeller, the turbine runner, and the stator is divided by a predetermined reference plane perpendicular to the axial direction of the output member, the fluid transmission device has a pump impeller on one side of the reference plane. The blade of the turbine runner and the blade of the stator are located on the other side of the reference plane. With this fluid transmission device, the pump capacity can be secured so that a sufficient amount of fluid circulates in the torus. Therefore, even if the entire device (torus) is downsized (flattened), the torque capacity Can be sufficiently secured.

  Further, it is preferable that the fluid inlet side end and the fluid outlet side end of the blade of the pump impeller extend in parallel to the reference plane. By adopting such a configuration, it is possible to secure the maximum pump capacity.

  Furthermore, it is preferable that the projected area of the blade of the turbine runner with respect to the meridian plane is at least half of the area of the torus region on the turbine runner side of the reference plane. By adopting such a configuration, it is possible to make the fluid transmission device compact while maintaining good torque transmission efficiency.

  According to the present invention, it is possible to realize a fluid transmission device that can be easily downsized while sufficiently securing a torque capacity.

  Hereinafter, the best mode for carrying out the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a partial cross-sectional view showing a torque converter as an example of a fluid transmission device according to the present invention. The torque converter 1 is applied to a vehicle equipped with an engine. As shown in FIG. 1, a front cover (input member) 2, a pump impeller (fluid transmission element) 3, a turbine runner (fluid transmission element) 4, including a turbine hub (output member) 5, a stator 6, a damper unit 7, and a lockup clutch mechanism 8. An engine rotation shaft (not shown) is fixed to the front cover 2. Further, an input shaft (not shown) of an automatic transmission (AT) or a continuously variable transmission (CVT) (not shown) is fixed (spline fitting) to the turbine hub 5.

  The pump impeller 3 has a pump shell 3 a and a plurality of blades 3 b, and the pump shell 3 a is closely fixed to the front cover 2. Similarly, the turbine runner 4 has a turbine shell 4 a and a plurality of blades 4 b, and the turbine shell 4 a is fixed to the turbine hub 5. The pump impeller 3 on the front cover 2 side and the turbine runner 4 on the turbine hub 5 side face each other, and a stator 6 having a plurality of blades 6b rotatable coaxially with the input shaft is disposed between the two. The The stator 6 has a one-way clutch 9 whose rotational direction is set to only one direction. The stator 6 (and the one-way clutch 9) is a turbine between the hub 3c and the turbine hub 5 by thrust bearings 10a and 10b. It is positioned in the axial direction of the hub 5. These pump impeller 3, turbine runner 4 and stator 6 form a torus (annular flow path) for circulating hydraulic oil.

  Here, the torque converter 1 of the present embodiment, as shown in FIG. 1, when a torus (annular flow path) formed by the pump impeller 3, the turbine runner 4, and the stator 6 is divided by the reference plane RS, The blade 3b of the pump impeller 3 is positioned on the left side of the reference plane RS in the drawing, and the blade 4b of the turbine runner 4 and the blade 6b of the stator 6 are positioned on the right side of the reference plane RS in the drawing. The reference plane RS is a plane perpendicular to the axial direction of the turbine hub 5 and divides the torus formed by the pump impeller 3, the turbine runner 4 and the stator 6 into two substantially vertically at the center. Furthermore, in this embodiment, the fluid inlet side edge 3i and the fluid outlet side edge 3o of each blade 3b of the pump impeller 3 extend in parallel to the reference plane RS, that is, perpendicular to the axial direction of the turbine hub 5. Exist.

  In the torque converter 1 configured as described above, the pump capacity can be secured so that a sufficient amount of fluid circulates in the torus. Therefore, even if the entire device (torus) is downsized and flattened, the torque capacity Can be sufficiently secured. And it becomes possible to ensure pump capacity to the maximum by extending the fluid inlet side edge 3i and the fluid outlet side edge 3o of each blade 3b of the pump impeller 3 in parallel with the reference plane RS. . In the torque converter 1, the turbine shell 4a also serves as a so-called stator shell (side wall of the blade 6b), and a slight gap is formed between the blade 6b of the stator 6 and the turbine shell 4a. This makes it possible to reduce the size of the torus and increase the torque capacity at the low speed ratio.

  Further, in the present embodiment, the projected area of the blades 4b of the turbine runner 4 with respect to the meridian plane (the plane parallel to the paper surface including the axis of the turbine hub 5) is on the turbine runner 3 side (right side in the figure) with respect to the reference plane RS. The torus region (a region surrounded by the reference surface RS and the turbine shell 4a) is more than half the area of the meridian surface. As a result, it is possible to make the torque converter 1 compact while maintaining good torque transmission efficiency. In this case, the projected area of the turbine runner 4 on the meridian plane of the blade 4b and the projected area of the blade 6b of the stator 6 on the meridian plane in a region on the other side (right side in the figure) of the torus reference plane RS on the meridian plane The ratio is preferably 5: 5 to 7: 3 (turbine blade: stator blade).

  The pump impeller 3 according to the present embodiment includes a blade 3b as shown in FIG. 2 and a core member 30 as shown in FIG. In this case, the blade 3b having a substantially semicircular shape has two tabs 3t formed at a predetermined interval between the fluid inlet side edge 3i and the fluid outlet side edge 3o. The core member 30 is formed as a narrow annular member as shown in FIG. A plurality of slits 30s opened outward are formed radially at the outer peripheral edge of the core member 30, and a plurality of slits 30s opened inside are formed at the inner peripheral edge of the core member 30. Yes.

  Each tab 3t of the blade 3b is inserted into the slit 30s of the core member 30, and is bent in the circumferential direction of the core member 30, and is fixed to the core member 30 by a predetermined method. By adopting such a configuration, even if the size of the core member 30 is reduced, the stability of the blade 3b against the force in the circumferential direction can be ensured, so that the durability of the pump impeller 3 can be improved. It becomes. Of course, it goes without saying that such a configuration can be applied to the turbine runner 4.

  On the other hand, the damper unit 7 of the torque converter 1 is coupled to the turbine hub 5 together with the turbine shell 4a. As shown in FIG. 1, the damper unit 7 includes an intermediate plate 71, a plurality of springs (elastic bodies) 72, and guide plates 73 and 74. The intermediate plate 71 is formed as an annular member in which substantially trapezoidal protrusions are extended outward from a plurality of locations in the circumferential direction of the outer peripheral edge thereof, and the inner peripheral portion thereof is connected via a rivet or the like. The turbine hub 5 is fixed. A predetermined number of springs 72 are arranged between the protrusions of the intermediate plate 71, and the intermediate plate 71 and the springs 72 are sandwiched from both sides by the guide plates 73 and 74.

  The guide plates 73 and 74 are formed in an annular shape, and have spring holding portions 73a and 74a formed by opening a part of the plate outward and opening at a plurality of locations in the circumferential direction. The guide plate 73 and the guide plate 74 are connected (fixed) to each other by rivets or the like at a plurality of locations in the circumferential direction of the respective outer peripheral side edges. The intermediate plate 71 is held between the guide plates 73 and 74 so as to be rotatable relative to the guide plates 73 and 74, and the springs 72 arranged between the protrusions of the intermediate plate 71 are respectively corresponding spring holding portions. 73a and 74a. At this time, one outer end (the end opposite to the protrusion) of the spring 72 comes into contact with one end of the spring holding portions 73a and 74a.

  The lockup clutch mechanism 8 of the torque converter 1 is disposed between the above-described damper unit 7 and the front cover 2. As shown in FIG. 1, the lockup clutch mechanism 8 includes a lockup piston 80, a first friction disk (first friction member) 81, and a second friction disk (second friction member) 82. The lock-up piston 80 is formed in an annular shape, and the center portion thereof is slidably supported around the end portion 5a of the turbine hub 5 on the front cover 2 side. As a result, the lock-up piston 80 can move in the axial direction of the turbine hub 5, and can approach and separate from the front cover 2.

  In this embodiment, the inner peripheral side positioning end 80a of the lockup piston 80 fitted into the end 5a of the turbine hub 5 extends to the front cover 2 side. The front cover 2 is formed with a recess 2a so as to face the inner peripheral side positioning end 80a and the end 5a of the turbine hub 5, and between the end 5a and the recess 2a, A thrust bearing 10c is disposed. By adopting such a configuration, it is possible to reduce the space required for positioning the lockup piston 80 in the axial direction of the turbine hub 5 and disposing the thrust bearing 10c.

  As shown in FIGS. 1 and 4, the first friction disk 81 includes a main body 810 formed in an annular shape, and is disposed between the lockup piston 80 and the front cover 2. A friction plate 83 is fixed to the front and back surfaces (the surface on the lockup piston 80 side and the surface on the front cover 2 side) on the outer peripheral side of the main body 810. A plurality of grooves are formed radially on the inner edge of the main body 810, and each groove engages with the guide portion 11 a of the disk support member 11 fixed to the inner surface of the front cover 2. Thus, the first friction disk 81 is pivoted with respect to the disk support member 11 in a state where movement of the front cover 2 and the turbine hub 5 in the rotation direction (rotation with respect to the front cover 2 and the like) is restricted by the disk support member 11. It becomes slidable in the direction. That is, the first friction disk 81 is integrated with the front cover 2 in the rotational direction of the front cover 2 and the turbine hub 5, while being movable in the axial direction of the turbine hub 5 and the like with respect to the front cover 2.

  The second friction disk 82 also includes a main body 820 formed in an annular shape, and is disposed on the outer periphery of the guide plates 73 and 74 of the damper unit 7 and the lock-up piston 80 as shown in FIGS. Is done. The main body 820 includes a base portion 82 a extending in the radial direction of the turbine hub 5 and a plurality of splines 82 b extending from the base portion 82 a in the axial direction of the turbine hub 5. A friction plate 83 is fixed to the surface of the base portion 82a on the front cover 2 side.

  Further, as shown in FIG. 5, a recess 80 b is formed in the outer peripheral portion of the lockup piston 80 so as to correspond to the spline 82 b of the second friction disk 82. Similarly, recesses 73 b and 74 b are formed on the outer peripheral portions of the guide plates 73 and 74 constituting the damper unit 7 so as to correspond to the splines 82 b of the second friction disk 82. As shown in FIG. 5, each spline 82b of the second friction disk 82 is engaged with the recess 80b of the lockup piston 80 and the recesses 73b and 74b of the guide plates 73 and 74 so as to be slidable in the axial direction. It is done.

  As a result, the second friction disk 82 is integrated with the lockup piston 80 in the rotational direction (such as the turbine hub 5) and is movable in the axial direction (such as the turbine hub 5) with respect to the lockup piston 80. It becomes. Further, the second friction disk 82 is integrated with the guide plates 73 and 74 of the damper unit 7 in the rotational direction (such as the turbine hub 5) and is also (with respect to the guide plates 73 and 74, such as the turbine hub 5). It becomes movable in the axial direction. Accordingly, since the damper unit 7 (intermediate plate 71) is connected to the turbine hub 5 as described above, the second friction disk 82 is integrated with the turbine hub 5 in the rotational direction, and is connected to the turbine hub 5. On the other hand, it can move in the axial direction.

  Now, in the torque converter 1 configured as described above, when an engine (not shown) is operated and the front cover 2 and the pump impeller 3 rotate, the turbine runner 4 starts to be dragged by the flow of hydraulic oil. When the rotational speed difference between the pump impeller 3 and the turbine runner 4 is large, the stator 6 converts the flow of hydraulic oil into a direction that assists the rotation of the pump impeller 3. As a result, the torque converter 1 operates as a torque amplifier when the rotational speed difference between the pump impeller 3 and the turbine runner 4 is large. When the rotational speed difference between the two becomes small, the stator 6 idles via the one-way clutch 9. And act as a fluid coupling. That is, engine power is transmitted from the front cover 2 to the turbine hub 5 via the turbine runner 4 (working fluid).

  When a predetermined condition is satisfied after the vehicle starts (for example, when the vehicle speed reaches a predetermined value), the lock-up clutch mechanism 8 is activated, and the power transmitted from the engine to the front cover 2 is used as an output member. Is directly transmitted to the turbine hub 5 (mechanically [directly transmitted)], whereby the engine and the input shaft of the transmission are mechanically directly connected. Further, the fluctuation of torque transmitted from the front cover 2 to the turbine hub 5 is absorbed by the damper unit 7.

  At the time of such lock-up, hydraulic oil is supplied to an oil chamber defined between the lock-up piston 80 and the pump shell 3a by a hydraulic device (not shown). Thereby, the lock-up piston 80 is pressed by the flow of the hydraulic oil from the oil chamber and moves toward the front cover 2. Accordingly, the first friction disk 81 and the second friction disk 82 are pressed by the lock-up piston 80 and moved toward the front cover 2.

  Accordingly, the first friction disk 81 and the second friction disk 82 are sandwiched between the lockup piston 80 and the front cover 2. The friction plate 83 on one side (left side in the figure) of the first friction disk 81 is in frictional contact with the lockup piston 80, and the friction plate 83 of the second friction disk 82 is in frictional contact with the front cover 2. The friction plate 83 on the other side (the right side in the figure) of the first friction disk 81 is in frictional contact with the base portion 82a of the second friction disk 82, so that the first friction disk 81 and the second friction disk 82 are in frictional contact with each other. To do. As a result, the lockup piston 80 and the front cover 2 are firmly connected, and both rotate together. In the torque converter 1, when hydraulic oil is supplied to the oil chamber defined between the front cover 2 and the lockup piston 80, the connection between the front cover 2 and the lockup piston 80 is cut off, There will be a difference in rotation.

  When the lockup piston 80 and the front cover 2 are connected and both of them start rotating, the rotation (power) of the front cover 2 and the lockup piston 80 is transmitted to the turbine hub 5 as an output member via the damper unit 7. Directly transmitted mechanically. At this time, in this embodiment, the power transmission path from the front cover 2 to the damper unit 7 (guide plates 73 and 74) is divided into three systems as indicated by arrows in FIG.

  In other words, the first power transmission path transmits power from the front cover 2 to the damper unit 7 in the order of the front cover 2 → the friction plate 83 → the second friction disk 82 → the damper unit 7. Further, the second power transmission path is configured such that the front cover 2 → the disk support member 11 → the first friction disk 81 → the friction plate 83 → the second friction disk 82 → the damper unit 7 in the order of power from the front cover 2 to the damper unit 7. Is to communicate. The third power transmission path is from the front cover 2 in the order of the front cover 2 → the disk support member 11 → the first friction disk 81 → the friction plate 83 → the lockup piston 80 → the second friction disk 82 → the damper unit 7. The power is transmitted to the damper unit 7.

  As described above, in the torque converter 1, the power (torque) from the front cover 2 is transmitted to the damper unit 7 (turbine hub 5) in a state of being distributed in the first to third power transmission paths. . Therefore, in the torque converter 1, it is possible to reduce the stress applied to each member and reliably prevent the stress from concentrating on a specific part. In particular, in the present embodiment, the torque transmitted from the front cover 2 to the damper unit 7 (turbine hub 5) via the lock-up piston 80 can be greatly reduced as compared with the conventional one. Therefore, the lock-up piston 80 can be easily thinned (downsized).

  In the torque converter 1, the lock-up piston 80 and the damper unit 7 (turbine hub 5) are linked via the second friction disk 82, so the lock-up piston 80 and the damper unit 7 (turbine hub 5). Can be simplified (reduced), and the number of parts required for the engagement can be reduced. The splines 82b of the second friction disk 82, the lock-up piston 80, and the recesses 80b, 73b, 74b of the guide plates 73 and 74 can all be formed relatively easily and at low cost. Therefore, according to the present invention, it is possible to reduce the number of parts of the lockup clutch mechanism 8 and reduce the cost of the torque converter 1.

It is sectional drawing which shows the fluid transmission apparatus by this invention. It is a schematic diagram which shows the braid | blade of the pump impeller contained in the fluid transmission apparatus of FIG. It is a schematic diagram which shows the core member of the pump impeller contained in the fluid transmission apparatus of FIG. It is a principal part enlarged view of the fluid transmission apparatus of FIG. It is a principal part enlarged view of the fluid transmission apparatus of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Torque converter 2 Front cover 3 Pump impeller 3a Pump shell 3b Blade 3i Fluid inlet side edge 3o Fluid outlet side edge 4 Turbine runner 4a Turbine shell 4b Blade 5 Turbine hub 6 Stator 6b Blade 7 Damper unit 8 Lock-up clutch mechanism 11 Disc support members 73, 74 Guide plates 73b, 74b, 80b Recess 80 Lock-up piston 81 First friction disc 82 Second friction disc 82a Base 82b Spline 83 Friction plate RS Reference surface S Input shaft

Claims (3)

In a fluid transmission device that transmits power from an input member to an output member,
A pump impeller attached to the input member;
A turbine runner attached to the output member and facing the pump impeller;
A stator for guiding the fluid flowing out of the turbine runner to the pump impeller,
When a torus formed by the pump impeller, the turbine runner, and the stator is divided by a predetermined reference plane perpendicular to the axial direction of the output member, a blade of the pump impeller is positioned on one side of the reference plane. The fluid transmission device, wherein the turbine runner blade and the stator blade are located on the other side of the reference surface.   2. The fluid transmission device according to claim 1, wherein a fluid inlet side end and a fluid outlet side end of the blade of the pump impeller extend in parallel to the reference surface.   3. The fluid transmission device according to claim 1, wherein a projected area of a blade of the turbine runner with respect to a meridian plane is half or more of a torus region on the turbine runner side with respect to the reference plane.

Images