JP2008202687A - Rotation transmission device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a reliable rotation transmission device capable of surely preventing erroneous engagement of a two-way clutch. <P>SOLUTION: An electromagnetic clutch 20 is juxtaposed to the two-way clutch 10. The electromagnetic clutch 20 comprises an armature 21, a rotor 22 confronting the armature 21, an electromagnet 23 for attracting the armature 21 to the rotor 22 by supplying current, and a receding spring 24 for energizing the armature 21. A tapered recession 27 is formed on an inner peripheral part of a surface confronting an inner ring 2 of the armature 21, an end of the inner ring 2 is fitted in the tapered recession 27 when the armature 21 is separated from the rotor 22 by pushing of the receding spring 24 by disengagement of the two-way clutch 10, and relative rotation of the inner ring 2 and a retainer 14 is prevented by frictional engagement of a tapered surface 28 formed on an end part outer periphery of the inner ring 2 and a tapered inner surface 29 of the tapered recession 27, and erroneous engagement of an engagement element 13 is prevented. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a rotation transmission device used for switching between power transmission and cutoff on a power transmission path.

  In an FR-based four-wheel drive vehicle, a rotation transmission device that transmits and interrupts driving force to a front wheel as an auxiliary drive wheel has been conventionally known.

  In the rotation transmission device described in Patent Document 1, a two-way clutch is incorporated between a large-diameter portion formed on the input-side member and an outer ring provided on the outside thereof, and an electromagnetic clutch attached to the two-way clutch is used. By controlling the engagement and disengagement of the two-way clutch, the input side member and the outer ring are coupled by the engagement of the two-way clutch, and rotational torque is transmitted between the input side member and the outer ring. Yes.

  Here, the two-way clutch forms a cylindrical surface on the inner periphery of the outer ring, and forms a wedge-shaped space in which both ends in the circumferential direction are narrow with the cylindrical surface on the outer periphery of the large-diameter portion of the input side member A cam surface is provided, and an engaging element made of a roller is incorporated between the cam surface and the cylindrical surface, and the engaging element is engaged with the cylindrical surface and the cam surface by the relative rotation of the cage that holds the engaging element and the input side member. I try to let them. Further, a switch spring is incorporated between the input side member and the cage, and the cage is elastically held at a neutral position where the engagement element is disengaged from the cylindrical surface and the cam surface by the switch spring.

  On the other hand, an electromagnetic clutch is an armature that is prevented from rotating by a cage and is supported so as to be movable in the axial direction, and a rotor that is incorporated in a rotor guide connected to the opening end of the outer ring and faces the armature in the axial direction. And an electromagnet that faces the rotor in the axial direction, and a separation spring that urges the armature in a direction away from the rotor. The armature is attached to the outer ring by attracting the armature to the rotor by energizing the electromagnet. The engaging member is engaged with the cylindrical surface and the cam surface by relative rotation of the input side member.

  By the way, in the rotation transmission device described in Patent Document 1, when the input side member rotates at high speed, the input side member and the roller held by the cage rotate together, and the centrifugal force acting on the roller is rotated. Due to the force, the roller moves radially outward to contact the cylindrical surface of the outer ring, and the dragging torque acting on the contact portion causes the input side member and the cage to rotate relative to each other, causing the roller to miss the cam surface and cylindrical surface. There is a risk of engagement.

  Further, when the input side member is suddenly accelerated and decelerated in the idling state, the input side member and the roller are elastically coupled to the input side member via the switch spring by the inertia force of the input side member and the roller. There is a possibility that the cage, the armature and the roller rotate relative to each other and the roller misengages with the cam surface and the cylindrical surface.

  In order to solve such a problem, in the rotation transmission device described in Patent Document 2, when the armature is separated from the rotor by the pressing of the separation spring, the cylindrical portion or protrusion provided on the armature is connected to the inner diameter of the switch spring. The switch spring is prevented from contracting, and the cage and the cam ring (inner ring) are prevented from rotating relative to each other to prevent the engagement element from misengaging.

JP 2005-249003 A JP 2005-83560 A

  By the way, in the rotation transmission device described in Patent Document 2, since the axial movement distance of the armature that moves to the rotor side when the electromagnet is energized is extremely small, a sufficient amount of engagement between the cylindrical portion and the protrusion with respect to the switch spring is ensured. In some cases, there is a possibility of misengagement, and there is a point to be improved in order to increase the reliability of preventing the misengagement.

  An object of the present invention is to provide a reliable rotation transmission device capable of reliably preventing misengagement of a two-way clutch.

  In order to solve the above-described problems, in the present invention, an engagement element and a retainer that retains the engagement element are provided between the outer ring and an inner ring that is incorporated therein, and the relative rotation of the retainer and the inner ring is achieved. As a result, a two-way clutch for coupling the outer ring and the inner ring by incorporating the engagement element into the opposing surfaces of the outer ring and the inner ring is incorporated, and the engagement element is connected to the outer ring and the inner ring between the cage and the inner ring of the two-way clutch. A switch spring that elastically holds the cage is incorporated in a neutral position where the biting is released, and an electromagnetic clutch that controls engagement and disengagement of the two-way clutch is provided in addition to the two-way clutch. A clutch has a disc-shaped armature having a hole in the center that is prevented from rotating with respect to the retainer and is movably supported in the axial direction, and is connected to the opening end of the outer ring in the axial direction. A rotation transmission device comprising: a rotor facing the rotor; an electromagnet that is axially opposed to the rotor and attracts the armature to the rotor by energization; and a separation spring that urges the armature in a direction away from the rotor. A tapered concave portion is formed in the inner peripheral portion of the opposing surface to fit the end portion of the inner ring in a state where the armature is separated from the rotor. The outer peripheral end portion of the inner ring is formed on the tapered inner surface of the tapered concave portion. A configuration with a suitable tapered surface was adopted.

  As described above, a tapered recess is formed in the inner periphery of the surface facing the inner ring of the armature, and the end of the inner ring is fitted, and the outer periphery of the end of the inner ring is adapted to the tapered inner surface of the tapered recess. By providing a tapered surface and forming a conical clutch between the inner ring and the armature, the end of the inner ring is fitted into the tapered recess of the armature during idling of the inner ring where the two-way clutch is disengaged, The tapered inner surface of the tapered recess is frictionally engaged with the tapered surface of the inner ring, and the armature is coupled to the inner ring. For this reason, the inner ring and the cage do not rotate relative to each other, and it is possible to reliably prevent the two-way clutch from misengaging when the inner ring is idling and to obtain a highly reliable rotation transmission device. it can.

  Embodiments of the present invention will be described below with reference to the drawings. As shown in FIG. 1, an inner ring 2 is incorporated inside the outer ring 1, and the outer ring 1 and the inner ring 2 are supported relatively rotatably by a bearing 3.

  An input shaft 4 is inserted inside the inner ring 2, the input shaft 4 and the inner ring 2 are prevented from rotating by a serration 5, and the input shaft 4 and the inner ring 2 rotate together.

  A two-way clutch 10 is incorporated between the outer ring 1 and the large-diameter portion 2 a formed on the inner ring 2. As shown in FIGS. 1 and 3, the two-way clutch 10 forms a cylindrical surface 11 on the inner periphery of the outer ring 1, and the outer periphery of the large-diameter portion 2 a of the inner ring 2 is circumferential with the cylindrical surface 11. A flat cam surface 12 that forms a narrow wedge-shaped space at both ends is provided at intervals in the circumferential direction, and an engagement element 13 made of a roller is incorporated between each cam surface 12 and the cylindrical surface 11. Is held by the cage 14.

  In addition, a switch spring 15 partially cut off in the circumferential direction is incorporated in the end portion of the inner ring 2, and a pair of pressing pieces 15 a formed outward from both ends of the switch spring 15 are formed on the end surface of the inner ring 2. It inserts into the notch 17 provided in the edge part of the holder | retainer 14 from the notch part 16, presses the opposing side surface in the circumferential direction of the notch part 16 and the notch 17 in the opposite direction, and the engagement element 13 is pressed by the pressing. Retains the retainer 14 in a neutral position where the engagement is released from the cylindrical surface 11 and the cam surface 12.

  As shown in FIG. 1, an electromagnetic clutch 20 that controls the engagement and disengagement of the two-way clutch 10 is provided between the outer ring 1 and the cage 14 together with the two-way clutch 10. Yes.

  The electromagnetic clutch 20 is a disk-shaped armature 21 having a hole in the center disposed opposite to the end face of the cage 14, a rotor 22 facing the armature 21 in the axial direction, and facing the rotor 22 in the axial direction. An electromagnet 23 and a separation spring 24 that urges the armature 21 in a direction away from the rotor 22 are provided.

  The armature 21 has an engagement hole 25, and a projection piece 26 formed at the end of the retainer 14 is engaged with the engagement hole 25, and the armature 21 is engaged by the engagement of the projection piece 26 and the engagement hole 25. Is prevented from rotating with respect to the retainer 14 and is movable in the axial direction.

  Further, as shown in FIG. 2, the armature 21 is formed with a tapered concave portion 27 in the inner peripheral portion of the end surface facing the inner ring 2, and the armature 21 is separated from the rotor 22 by the pressing of the separation spring 24. When moved, the end of the inner ring 2 is fitted into the tapered recess 27, and the tapered surface 28 formed on the outer periphery of the end of the inner ring 2 is frictionally engaged with the tapered inner surface 29 of the tapered recess 27. It is like that.

  As shown in FIG. 1, the rotor 22 has cylindrical portions 22 a and 22 b on the outer periphery and the inner periphery, and the outer peripheral cylindrical portion 22 a is fitted into a cylindrical rotor guide 30 connected to the opening end of the outer ring 1. It is positioned in the axial direction and is prevented from rotating.

  The electromagnet 23 includes an electromagnetic coil 23a and a core 23b that supports the electromagnetic coil 23a. When the electromagnetic coil 23a is energized, a magnetic flux flows through the core 23b, the rotor 22, and the armature 21, and an attractive force is applied to the armature 21. It has come to be.

  The rotation transmission device shown in the embodiment has the above-described structure. FIGS. 1 and 2 show a cut-off state of the electromagnet 23 with respect to the electromagnetic coil 23a, and the armature 21 is separated from the rotor 22 and An air gap is formed between the two. The two-way clutch 10 is in a disengaged state. For this reason, even if the inner ring 2 rotates, the rotation is not transmitted to the outer ring 1 and the inner ring 2 rotates idle.

  When the electromagnetic coil 23 a of the electromagnet 23 is energized in the idling state of the inner ring 2, magnetic flux flows between the core 23 b, the rotor 22, and the armature 21, and the armature 21 is attracted to the rotor 22.

  As the armature 21 is attracted, the frictional resistance acting on the attracting surface becomes the rotational resistance of the cage 14, so that the inner ring 2 and the cage 14 rotate relative to each other. By the relative rotation, the engaging element 13 is engaged with the cylindrical surface 11 and the cam surface 12, the two-way clutch 10 is engaged, and the rotation of the inner ring 2 is transmitted to the outer ring 1. Further, the switch spring 15 is elastically deformed by the relative rotation of the inner ring 2 and the cage 14.

  For this reason, when the energization to the electromagnetic coil 23a is interrupted, the armature 21 is separated from the rotor 22 by the pressing force of the separation spring 24, the cage 14 is rotated by the restoring elasticity of the switch spring 15, and the engaging element 13 is cylindrical. 11 and the neutral position where the cam surface 12 is disengaged, the two-way clutch 10 is disengaged, the rotation transmission from the inner ring 2 to the outer ring 1 is interrupted, and the inner ring 2 idles. .

  Here, when the armature 21 is moved away from the rotor 22 by the pressing force of the separation spring 24, the end of the inner ring 2 is fitted into a tapered recess 27 formed in the armature 21, as shown in FIG. Then, the tapered surface 28 on the outer periphery of the end portion frictionally engages with the tapered inner surface 29 of the tapered recess 27, and the armature 21 is coupled to the inner ring 2.

  For this reason, when the rotation transmission device is idling, the inner ring 2 is rotated at a high speed, and the engaging member that rotates together with the inner ring 2 comes into contact with the cylindrical surface 11 of the outer ring 1 by centrifugal force and is held by drag torque acting on the contact portion. Even if a rotational resistance exceeding the spring force of the switch spring 15 is loaded on the cage 14, the cage 14 does not rotate relative to the inner ring 2. For this reason, the engaging element 13 is not misengaged with the cylindrical surface 11 and the cam surface 12.

  Even if a large inertia force is applied to the cage 14 and the engagement element 13 elastically coupled to the inner ring 2 due to the sudden acceleration / deceleration of the inner ring 2, the inner ring 2, the cage 14 and the engagement element 13 are relatively rotated. This can also be prevented.

Longitudinal front view showing an embodiment of a rotation transmission device according to the present invention Enlarged sectional view showing the armature in a separated state Sectional view along line III-III in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Outer ring 2 Inner ring 10 Two-way clutch 11 Cylindrical surface 12 Cam surface 13 Engagement element 14 Retainer 15 Switch spring 20 Electromagnetic clutch 21 Armature 22 Rotor 23 Electromagnet 24 Separation spring 27 Tapered recess 28 Tapered surface 29 Tapered inner surface

Claims (1)

Between the outer ring and the inner ring incorporated in the inner ring, there is an engagement element and a retainer for holding the engagement element, and the engagement element is engaged with the opposing surfaces of the outer ring and the inner ring by the relative rotation of the retainer and the inner ring. In addition, a two-way clutch that connects the outer ring and the inner ring is incorporated, and the retainer elastically moves the retainer between the retainer and the inner ring of the two-way clutch in a neutral position where the engagement with the outer ring and the inner ring is released. A switch spring for holding is incorporated, and an electromagnetic clutch for controlling engagement and disengagement of the two-way clutch is provided in addition to the two-way clutch, and the electromagnetic clutch is prevented from rotating with respect to the cage, And a disk-shaped armature having a hole in the center supported so as to be movable in the axial direction, a rotor connected to the opening end of the outer ring and facing the armature in the axial direction, and facing the rotor in the axial direction, Energized Thus an electromagnet for attracting the armature to the rotor, the rotation transmitting device comprising a separating spring biasing the armature in a direction away from the rotor,
A tapered recess is formed in the inner peripheral portion of the surface facing the inner ring of the armature so that the end of the inner ring fits in a state where the armature is separated from the rotor, and the tapered recess is formed on the outer periphery of the end of the inner ring. A rotation transmission device characterized in that a taper surface adapted to the taper-shaped inner surface is provided.

Images