JP2008121710A - One-way clutch and fluid transmission device incorporating the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve such a problem that a thrust race is required for a conventional one-way clutch incorporated in a fluid transmission device, thus needing an installation space for the race. <P>SOLUTION: The one-way clutch 34 has an inner ring 35, an outer ring 36 encircling the inner ring 35, a plurality of sprags 38 incorporated between the inner ring 35 and the outer ring 36, and a pair of end bearings 42 fitted between the inner ring 35 and the outer ring 36 in a relatively rotatable manner to oppose to each other across the sprags 38 for specifying a space between the inner ring 35 and the outer ring 36. It comprises an inside holding groove 43 annularly formed in the outer peripheral face of the inner ring 35, an outside holding groove 44 annularly formed in the inner peripheral face of the outer ring 36, an inside protruded portion 45 protruded on the inner peripheral face of the end bearing 42 for slidably engaging with the inside holding groove 43 of the inner ring 35, and an outside protruded portion 46 protruded on the outer peripheral face of the end bearing 42 for slidably engaging with the outside holding groove 44 of the outer ring 36. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a one-way clutch using sprags and a fluid transmission device incorporating the same.

  In a one-way clutch using a sprag, it is necessary to accurately dispose the sprag between the inner ring and the outer ring. For this reason, in addition to a retainer that accommodates the sprags at regular intervals, and a ribbon spring that applies a spring force to contact the sprags with the outer peripheral surface of the inner ring and the inner peripheral surface of the outer ring, these are held between the inner ring and the outer ring. It is necessary to use a pair of end bearings.

  As a typical mechanical apparatus incorporating such a one-way clutch, a torque converter as shown in Patent Document 1 is known. In the torque converter, a one-way clutch is incorporated between the stator and the support cylinder integral with the transmission case to define the rotation direction of the stator.

JP 2004-132526 A

  In the one-way clutch disclosed in Patent Document 1, in order to prevent the end bearing from coming off from between the inner ring and the outer ring, a pair of thrust traces that can be brought into sliding contact with the side end surfaces of the inner ring and the outer ring are provided via a snap ring. Attached to the stator.

  Since the annular thrust race is opposed to the one-way clutch so as to cover the gap between the inner ring and the outer ring, the flow of hydraulic oil supplied into the torque converter may be hindered by the thrust trace. is there. There is also a problem that the dimension along the rotation axis of the torque converter increases by the thickness of the thrust trace.

  An object of the present invention is to provide a one-way clutch that eliminates the thrust trace and promotes a smooth flow of hydraulic oil and does not require an increase in the dimension along the rotation axis, and a fluid transmission device incorporating the one-way clutch. It is to provide.

  In the first aspect of the present invention, the inner ring, the outer ring arranged so as to surround the inner ring, a plurality of sprags incorporated between the inner ring and the outer ring, and the above-mentioned so as to face each other with the sprags interposed therebetween. A one-way clutch that is fitted between an inner ring and an outer ring so as to be relatively rotatable and has a pair of end bearings that define a distance between the inner ring and the outer ring, and has an annular shape formed on the outer peripheral surface of the inner ring. An inner holding groove, an annular outer holding groove formed on the inner peripheral surface of the outer ring, and an inner peripheral surface of the end bearing projectingly slidably engage with the inner holding groove of the inner ring. An inner protrusion and an outer protrusion projecting from the outer peripheral surface of the end bearing and slidably engaged with an outer holding groove of the outer ring are provided.

  In the present invention, the relative rotational directions of the inner ring and the outer ring are always restricted to only one direction by the sprags. The inner and outer protrusions of the end bearing are slidably engaged with the inner and outer holding grooves of the inner ring and the outer ring, respectively. Even if the inner ring and the outer ring rotate relative to each other, the end bearing is inserted between the outer ring and the inner ring. There will be no problem that will be lost.

  In the one-way clutch according to the first aspect of the present invention, it is preferable that the inner protrusion and the outer protrusion of the end bearing are each elastically deformable in the radial direction.

  According to a second aspect of the present invention, an input side rotating element to which an input member is coupled, an output side rotating element to which an output member is coupled, and the input side rotating element and the output side rotating element are interposed. And a one-way clutch incorporated between the stator and a fixing member, wherein the one-way clutch is according to the first aspect of the present invention, and an inner ring thereof is the fixed The outer ring is connected to the stator while being connected to the member.

  In the present invention, the rotation direction of the outer ring and the stator integrated with the outer ring is always restricted to only one direction by the sprags with respect to the inner ring connected to the fixing member. The inner and outer protrusions of the end bearing are slidably engaged with the inner and outer holding grooves of the inner ring and the outer ring, respectively. Even if the outer ring rotates together with the stator, the end bearing comes out from between the outer ring and the inner ring. Defects that come off do not occur.

  According to the one-way clutch of the present invention, an annular inner holding groove formed on the outer peripheral surface of the inner ring, an outer holding groove formed on the inner peripheral surface of the outer ring, and the inner peripheral surface of the end bearing project. An inner protrusion that slidably engages with the inner holding groove of the inner ring, and an outer protrusion that projects from the outer peripheral surface of the end bearing and slidably engages with the outer holding groove of the outer ring. Thus, the end bearing can be prevented from coming off from the inner ring and the outer ring. As a result, it is not necessary to use a conventional thrust bearing race, and the number of parts can be reduced, and the one-way clutch can be made more compact.

  When the inner and outer protrusions of the end bearing can be elastically deformed in the radial direction, when the end bearing is mounted between the inner ring and the outer ring, a simple press-fitting operation can be performed without using a special jig. It can be installed quickly.

  According to the fluid transmission device of the present invention, the one-way clutch incorporated between the stator and the fixed member is the first embodiment of the present invention, and the inner ring is connected to the fixed member and the outer ring is connected to the stator. As a result, it is no longer necessary to use a race to prevent the end bearing from falling off between the inner ring and the outer ring. Thereby, the reduction of the number of parts can be combined with the reduction of the weight of the fluid transmission device, and the flow of the hydraulic oil passing through the one-way clutch can be made smoother.

  An embodiment in which a fluid transmission device according to the present invention is applied to a vehicle torque converter will be described in detail with reference to FIGS. However, the present invention is not limited to such an embodiment, and all changes and modifications included in the concept of the present invention described in the claims are possible. The one-way clutch belongs to the spirit of the present invention. Of course, the present invention can be applied to any other technology that requires the above.

  FIG. 1 shows a cross-sectional structure (upper half) of the torque converter in the present embodiment. The torque converter 10 according to the present embodiment includes an input side rotating element A including a pump impeller 11 and a front cover 12, a turbine runner 13, and a turbine hub 15 integrally connected to the turbine runner 13 via a rivet 14. A lock-up clutch device C including an output-side rotation element B, a lock-up piston 17 having a friction plate 16 that presses against the front cover 12 joined to an outer peripheral end portion, a lock-up piston 17 of the lock-up clutch device C, and an output And a damper device D disposed across the turbine hub 15 of the side rotating element B.

  The pump impeller 11 described above has a blade 18 and an annular pump shell 19 having the blade 18 attached to the inside. In addition to the pump impeller 11, the input side rotating element A is joined to a pump shell 19 at an outer peripheral edge portion, and a nut member 20 for fixing a drive plate connected to a crankshaft of an engine (not shown) as an input member. Further, a front cover 12 that is welded to the inner periphery of the pump shell 19 and an extension sleeve 21 whose outer periphery is joined to the inner periphery of the pump shell 19 are further included.

  The turbine runner 13 of the output side rotating element B includes a blade 22 that faces the pump impeller 11 and a turbine shell 23 that holds the blade 22. The output-side rotating element B has a transmission (not shown) as an output member, for example, an automatic transmission (AT) using a plurality of planetary gear units, a pair of pulleys capable of changing the groove width, and an endless coil wound around them. An input shaft 1 of a continuously variable transmission (CVT) using a belt is connected. In the present embodiment, a female spline 15 a is formed on the inner peripheral surface of the turbine hub 15, and a male spline 1 a formed on the outer peripheral surface of the transmission input shaft 1 is fitted therein. A seal ring 24 is press-fitted into the inner peripheral surface of the boss portion 15b of the turbine hub 15 of the output side rotating element B, and the inner peripheral surface of the boss portion 15b and the outer peripheral surface of the shaft end portion of the transmission input shaft 1 are connected. The gap between them is sealed. In addition, a thrust receiving member 25 that restricts displacement of the turbine hub 15 along a direction parallel to the rotation axis 10 a of the torque converter 10 is incorporated between the turbine hub 15 and the front cover 12. The thrust receiving member 25 passes automatic transmission oil or CVT oil (hereinafter collectively referred to as hydraulic oil) along the radial direction (vertical direction in FIG. 1) of the torque converter 10. A permissible oil passage (not shown) is defined.

  A cylindrical boss portion 17 a that protrudes toward the turbine hub 15 is formed at the radially inner end of the lock-up piston 17, and the rotational axis 10 a of the torque converter 10 with respect to the annular groove portion 15 c formed in the turbine hub 15. Are slidably fitted along a direction parallel to the. A seal ring 26 is mounted between the groove portion 15c of the turbine hub 15 and the boss portion 17a of the lockup piston 17 to seal the gap between them. The lockup clutch device C having the lockup piston 17 can hold the front cover 12 and the lockup piston 17 in a directly connected state by pressing the friction plate 16 of the lockup piston 17 integrally with the front cover 12. It is what I did. More specifically, the hydraulic oil pressure supplied to the engagement side oil chamber 27 defined between the lockup piston 17 and the pump shell 19, and between the front cover 12 and the lockup piston 17. A differential pressure from the hydraulic pressure of the hydraulic oil supplied to the defined engagement release side oil chamber 28 is controlled via a hydraulic control device (not shown). As a result, the lock-up piston 17 can be displaced along the direction facing the front cover 12, that is, the direction parallel to the rotation axis 10a of the torque converter 10. Thus, the friction plate 16 can be held in a completely non-contact state with respect to the front cover 12 and can also be held in a half-clutch state in which the front cover 12 and the friction plate 16 of the lockup piston 17 are slidably contacted. It becomes possible.

  In this case, the lockup piston 17 is displaced toward the turbine hub 15 in a torque converter function region where rotation of the stator 29 described later does not occur. As a result, the front cover 12 and the friction plate 16 of the lock-up piston 17 are not in contact with each other, that is, the lock-up clutch device C is not connected. As a result, the power from the input side rotating element A is transmitted to the output side rotating element B in a state where the torque is enhanced via the hydraulic oil. Conversely, in the torque converter non-functional region where the rotational speeds of the input-side rotating element A and the output-side rotating element B are substantially equal and the stator 29 idles, the lock-up piston 17 is displaced toward the front cover 12 to lock up. The friction plate 16 of the piston 17 and the front cover 12 are brought into close contact with each other. This is controlled via a hydraulic pressure control circuit so that the hydraulic pressure of the hydraulic oil supplied to the engagement side oil chamber 27 becomes relatively higher than the hydraulic pressure of the hydraulic oil supplied to the engagement release side oil chamber 28. Is made by As a result, the input side rotating element A and the output side rotating element B are integrally coupled via the lock-up clutch device C, and the driving force of the input side rotating element A does not pass through the hydraulic oil and passes through the damper device D. To the output side rotating element B.

  A damper device D disposed between the turbine hub 15 and the lockup piston 17 includes an annular drive plate 31 integrally connected to the lockup piston 17 of the lockup clutch device C via a rivet 30, and an internal drive plate 31. An annular driven plate 32 whose peripheral end is integrally joined to the outer peripheral edge of the turbine hub 15 via the rivet 14 together with the inner peripheral end of the turbine shell 23, and straddles the drive plate 31 and the driven plate 32. And a spring member 33 arranged. Therefore, power transmission between the drive plate 31 and the driven plate 32 is performed via the spring member 33.

  The torque converter 10 according to the present embodiment includes a stator 29 interposed between the turbine runner 13 and the pump impeller 11, a one-way clutch 34 that allows the stator 29 to rotate only in the same direction as the rotation direction of the turbine runner 13, and the like. It also has more.

  The stator 29 held on the transmission case side (not shown) via the one-way clutch 34 again supplies hydraulic oil that flows into the turbine runner 13 of the output side rotating element B by the pump impeller 11 of the input side rotating element A again. This causes a known torque increase.

  FIG. 2 shows an extracted enlarged cross-sectional structure of the one-way clutch 34 in the present embodiment, and FIG. 3 shows a further enlarged cross-sectional structure along the line III-III. In the present embodiment, the one-way clutch 34 includes an inner ring 35, an outer ring 36 fitted into the inner periphery of the stator 29, a pair of snap rings 37 that hold the outer ring 36 on the inner periphery side of the stator 29, and the inner ring 35 and the outer ring 36. The main part is composed of the sprag 38 held between the two. The outer ring 36 can rotate integrally with the stator 29, but the rotation direction is always defined only in one direction by the sprag 38. On the inner peripheral surface of the inner ring 35, there is a female spline 35a that fits into a male spline 2a formed at the tip of a support cylinder 2 as a fixing member of the present invention that constitutes a part of a transmission case (not shown). Is formed. A needle roller bearing 3 for holding them concentrically is incorporated between the transmission input shaft 1 and the support cylinder 2 to ensure smooth rotation of the transmission input shaft 1 with respect to the support cylinder 2. Yes. The sprag 38 is held by an inner retainer 39 and an outer retainer 40 for maintaining the posture of the sprag 38 uniformly, and a biasing force is applied to the inner ring 35 and the outer ring 36 by a ribbon spring 41. The inner retainer 39 and the outer retainer 40 are held by the pair of end bearings 42 mounted between the inner ring 35 and the outer ring 36 without dropping from between the inner ring 35 and the outer ring 36 together with the inner and outer retainers 39 and 40. The The pair of end bearings 42 are formed with communication holes 42a for defining a flow path of hydraulic oil that crosses the sprag 38, whereby the hydraulic oil is smoothly supplied to the engagement side oil chamber 27 side. Consideration is taken. In the case of the present embodiment, the race that covers the side end surfaces of the inner ring 35 and the outer ring 36 is not required, so that the flow of hydraulic oil across the one-way clutch 34 can be performed more smoothly than the conventional one.

  Two annular grooves 43 and 44 are formed on the outer peripheral surface of the inner ring 35 and the inner peripheral surface of the outer ring 36 with which the inner sliding contact portion 42b and the outer sliding contact portion 42c of the end bearing 42 are in sliding contact, respectively. The annular grooves 43 and 44 functioning as the inner holding groove and the outer holding groove of the present invention are for preventing the end bearing 42 from coming off from between the inner ring 35 and the outer ring 36, and for the inner and outer sides thereof. Protrusions 45 and 46 are formed on the inner sliding contact portion 42b and the outer sliding contact portion 42c of the end bearing 42, respectively. A plurality of these inner and outer protrusions 45, 46 are arranged at equal intervals along the circumferential direction of the annular grooves 43, 44, and project into the annular grooves 43, 44, thereby causing end bearings from the inner ring 35 and the outer ring 36. This prevents 42 from coming off. In this case, it is effective that the inner sliding contact portion 42b and the outer sliding contact portion 42c of the end bearing 42 that are in sliding contact with the outer peripheral surface of the inner ring 35 and the inner peripheral surface of the outer ring 36 are elastically deformable in the radial direction. That is, when the end bearing 42 is mounted between the inner ring 35 and the outer ring 36, the inner sliding contact portion 42b and the outer sliding contact portion 42c are elastically deformed, and the inner and outer protrusions 45 and 46 formed on these are contacted. It is desirable to set the fitting dimension so that elastic deformation is released when the inner ring 35 and the outer ring 36 are fitted into the annular grooves 43 and 44.

  It is also possible to make the inner and outer protrusions 45 and 46 continuous over the entire circumference of the inner sliding contact portion 42b and the outer sliding contact portion 42c. However, by forming intermittently along the circumferential direction of the annular grooves 43 and 44 as in this embodiment, the annular grooves 43 and 44 positioned between the protrusions 45 and 46 adjacent in the circumferential direction are operated. It can function as an oil reservoir for oil, which is advantageous in terms of lubricity between the inner ring 35 and the outer ring 36 and the end bearing 42. Further, the number of the annular grooves 43 and 44 and the number of projections 45 and 46 fitted to these can be appropriately changed according to the dimensions and the like of the one-way clutch 34, and the annular grooves 43 and 44 for one end bearing 42. Of course, it is also possible to form a plurality of each on the inner ring 35 and the outer ring 36.

  Thrust bearings 47 are interposed between the turbine hub 15 and the extension sleeve 21 and the one-way clutch 34, respectively, and the one-way clutch 34 can be rotated relative to the extension sleeve 21 and the turbine hub 15.

  In the above-described embodiment, the fluid transmission device according to the present invention is applied to the vehicle torque converter 10, but it is naturally possible to apply the fluid transmission device to a fluid transmission device that does not have a function of increasing the drive torque. In this case, the fluid transmission device may not have a lock-up clutch device or a damper device. Furthermore, it will be readily understood that the present invention can be applied to any mechanical device that needs to incorporate a one-way clutch in addition to the fluid transmission device.

It is sectional drawing showing the internal structure of one Embodiment which applied the fluid power transmission apparatus by this invention to the torque converter for vehicles, and shows only one side (upper half in a figure) on the boundary of the rotating shaft line. It is an extraction expanded sectional view of the part of the one-way clutch in the embodiment shown in FIG. FIG. 3 is a cross-sectional view along the circumferential direction of a fitting portion between an outer ring and one end bearing of the one-way clutch shown in FIG. 2.

Explanation of symbols

A Input side rotating element B Output side rotating element C Lock-up clutch device D Damper device 1 Input shaft 1a Male spline 2 Support cylinder 2a Male spline 3 Needle roller bearing 10 Torque converter 10a Rotating axis 11 Pump impeller 12 Front cover 13 Turbine runner 14 Rivet 15 Turbine hub 15a Female spline 15b Boss portion 15c Groove portion 16 Friction plate 17 Lock-up piston 17a Boss portion 18 Blade 19 Pump shell 20 Nut member 21 Extension sleeve 22 Blade 23 Turbine shell 24 Seal ring 25 Thrust receiving member 26 Seal ring 27 Engagement side oil chamber 28 Disengagement side oil chamber 29 Stator 30 Rivet 31 Drive plate 32 Driven plate 33 Spring member 34 One-way clutch 35 Inner ring 35a Female spline 36 Outer ring 37 Snap ring 38 Sprag 39 Inner retainer 40 Outer retainer 41 Ribbon spring 42 End bearing 42a Communication hole 42b Inner sliding contact part 42c Outer sliding contact part 43, 44 Annular groove 45 Inner projection part 46 Outer projection part 47 Thrust bearing

Claims (3)

Relative rotation between the inner ring and the outer ring so as to face each other with an inner ring, an outer ring arranged so as to surround the inner ring, a plurality of sprags incorporated between the inner ring and the outer ring, and sandwiching these sprags A one-way clutch that has a pair of end bearings that are fitted together and define a distance between the inner ring and the outer ring,
An inner holding groove having an annular shape formed on the outer peripheral surface of the inner ring;
An outer holding groove having an annular shape formed on the inner peripheral surface of the outer ring,
An inner protrusion protruding from the inner peripheral surface of the end bearing and slidably engaged with an inner holding groove of the inner ring;
A one-way clutch comprising: an outer protrusion protruding from an outer peripheral surface of the end bearing and slidably engaged with an outer holding groove of the outer ring.   The one-way clutch according to claim 1, wherein the inner protrusion and the outer protrusion of the end bearing are elastically deformable in the radial direction. An input side rotating element to which the input member is coupled;
An output side rotating element to which the output member is coupled;
A stator interposed between the input side rotation element and the output side rotation element;
A fluid transmission device comprising a one-way clutch incorporated between the stator and a fixed member,
The fluid transmission device according to claim 1 or 2, wherein the one-way clutch is an inner ring connected to the fixing member and an outer ring connected to a stator.

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