JP2007032682A - Rotation transmission device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To operate an electromagnetic clutch stably by reducing the influence of magnetic field from members other than a rotor to an armature. <P>SOLUTION: A wet type multiple disc clutch 7 capable of allowing and shutting off transmission of rotation between an outer ring 3 and an inner ring 5 is installed by supporting the inner ring 5 on an inner side of the outer ring 3 on the same shaft axis rotatably, and the allowance and shutting-off of transmission of rotation are controlled by bringing the rotor 12 and the armature 11 into contact mutually or separating them from each other by an electromagnet 13 and applying axial force by their mutual contact and separation from each other. Since an air gap t1 between the armature 11 and the rotor 12 is set to be smaller than a clearance t2 between a face 11b on the opposite side to a contact and separation face 11a of the armature 11 and an end face E of the inner ring 5 approaching the face 11b most and opposing to it and be smaller than a clearance t3 between a side peripheral face 11c of the armature 11 and an inner peripheral face F of a member approaching the side peripheral face 11c most and opposing to it, attraction force from the rotor 12 acts on the armature 11 the most strongly. For this reason, the armature 11 is hardly attracted by the members other than the rotor 12 to operate the electromagnetic clutch stably. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

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

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

For example, this rotation transmission device will be described with reference to FIG. 1 which is an explanatory view of an embodiment of the present invention. An output member (inner ring) 5 is provided inside an input member (outer ring) 3 to which a driving force from the transmission is input. Are coaxially mounted and supported rotatably in the housing 1, respectively, and the input member 3 and the output member 5 are relatively rotatable.
A wet multi-plate clutch 7 that couples the inner ring 5 and the outer ring 3 by a loaded axial force is incorporated between the outer ring 3 and the inner ring 5, and the wet multi-plate clutch 7 is disposed on one side in the axial direction of the wet multi-plate clutch 7. A clutch control device 10 is provided for controlling the coupling and decoupling of the wet multi-plate clutch 7 according to the load of the axial force applied to the plate clutch 7.

The clutch control device 10 includes an electromagnetic clutch portion 10A and an axial force load portion 10B that converts the rotational torque of the outer ring 3 into an axial force and loads the wet multi-plate clutch 7 when the electromagnetic clutch portion 10A is coupled.
The electromagnetic clutch portion 10A includes an armature 11 movable in the axial direction, a rotor 12 attached to the outer ring 3 and facing the armature 11 in the axial direction, and an electromagnet 13 facing the rotor 12 in the axial direction. By energizing the electromagnetic coil 13 a of the electromagnet 13, the armature 11 is attracted to the rotor 12 and the outer ring 3 and the armature 11 are coupled.

  In addition, the axial force load portion 10B incorporates a pressure plate 21 between the armature 11 and the wet multi-plate clutch 7, holds the pressure plate 21 around the inner ring 5, and supports it so as to be movable in the axial direction. 21 and the armature 11 are provided with cam grooves 22 and 23 each having a groove depth gradually decreasing from the center toward both ends in the circumferential direction, and a ball 24 is incorporated between the cam grooves 22 and 23 so that the pressure plate 21 The pressure plate 21 is moved in the axial direction by the relative rotation of the armature 11 to apply an axial force to the wet multi-plate clutch 7.

  In order to securely lock the wet multi-plate clutch 7 in the coupled state, the electromagnetic clutch for attracting the armature 11 to the rotor 12 must have a predetermined torque. In other words, the torque of the electromagnetic clutch needs to be at a level at which the suction can be maintained until the armature 11 is rotated relative to the pressure plate 21 and a certain amount of axial thrust is generated on the pressure plate 21.

Therefore, it is necessary to appropriately set the electromagnetic clutch air gap t1 so that the torque of the electromagnetic clutch can be maintained at a predetermined level. When setting this, of course, it is necessary to consider the tolerance of each part.
For this reason, the rotor 12 is screwed to the outer ring 3 positioned outside, and the air gap between the armature 11 and the rotor 12 is adjusted by adjusting the degree of screwing between the rotor 12 and the outer ring 3 related to the screwed portion. The t1 can be adjusted to a predetermined size. Further, after the adjustment, the lock nut 16 prevents the screwed portion from loosening.
JP 2005-48788 A

  However, when the gap t2 between the surface 11b opposite to the contact surface 11a of the armature 11 shown in FIG. 1 and the end surface E of the inner ring 5 is small, the magnetic field of the electromagnet 13 causes the outer ring 3 to move from the rotor 12 to the outer ring 3. After that, when the bearing 4, the clutch plate 8, the clutch plate 9, and the inner ring 5 flow in this order, the armature 11 is attracted to the end face E side of the inner ring 5 by the action of the magnetic field generated by the inner ring 5. is there. When the armature 11 is attracted to the inner ring 5 side when the electromagnetic clutch is applied, the rotation of the outer ring 3 is not reliably transmitted to the armature 11, and an appropriate axial force load and shaft are applied to the wet multi-plate clutch 7. It is not preferable because the force cannot be released.

  Similarly, when the gap t3 between the inner peripheral surface F of the outer ring 3 and the side peripheral surface 11c of the armature 11 shown in FIG. 1 is small, there is a problem that the armature 11 is attracted to the outer ring 3 by the action of the magnetic field generated by the outer ring 3. is there. If the armature 11 is attracted to the outer ring 3 when the electromagnetic clutch is applied, the movement of the armature 11 in the axial direction becomes dull. Therefore, as in the case described above, an appropriate shaft for the wet multi-plate clutch 7 is used. It is not preferable because force load and axial force cannot be released.

  Accordingly, an object of the present invention is to reduce the influence of a magnetic field from other than the rotor on the armature and to stably operate the electromagnetic clutch.

In order to solve the above problems, the present invention sets the air gap of the armature so as to be smaller than the gap with other members adjacent to the armature.
The attraction force acting on the magnetic body by the magnetic field becomes stronger as the distance from the magnetic field generation source to the attracted magnetic body becomes shorter, so the attraction force of the magnetic field from the rotor acts on the armature most strongly. For this reason, the armature becomes difficult to be attracted from other adjacent members other than the rotor, and the electromagnetic clutch can operate stably.

  Since the present invention reduces the influence of the magnetic field from other than the rotor on the armature, the electromagnetic clutch can operate stably.

As an embodiment of the above means, one of the input member and the output member is coaxially disposed inside the other, and the input member and the output member are rotatably supported around the axis in the housing, respectively. A wet multi-plate clutch that allows rotation transmission from the input member to the output member to be turned on and off by a loaded axial force is incorporated between the members. A clutch control device is provided on one side in the axial direction of the wet multi-plate clutch, and the clutch control device contacts and separates the rotor and the armature by energizing and shutting off the electromagnet fixed to the housing. The rotation transmission device converts the rotational torque of the input member into an axial force and loads the axial force on the wet multi-plate clutch.
In the rotation transmission device having the above configuration, the air gap between the armature and the rotor is smaller than the gap between the end face of the member that is closest to and opposite to the surface opposite to the contact surface of the armature with the rotor. It was.

  In this way, the armature has a larger suction force from the rotor than the suction force from the other member located adjacent to the surface on the opposite side of the rotor side. It becomes difficult to be affected by the suction force from other members located adjacent to each other. For this reason, the armature is appropriately connected to and separated from the rotor, and the electromagnetic clutch can operate stably.

  The same effect can be achieved even if the air gap between the armature and the rotor is made smaller than the gap between the side peripheral surface of the armature and the inner peripheral surface of the member closest to the side peripheral surface. Can do. That is, since the suction force from the rotor acts on the armature more than the suction force from other members located adjacent to the side (radial direction) of the armature, the other is located adjacent to the side. It becomes difficult to be influenced by the suction force from the member. For this reason, the armature is appropriately connected to and separated from the rotor, and the electromagnetic clutch can operate stably.

  As described above, the air gap between the armature and the rotor is determined by the gap between the surface on the opposite side of the contact surface of the armature with the rotor and the end surface of the member closest to the opposite surface. And the air gap is set to be smaller than the gap between the armature side peripheral surface and the inner peripheral surface of the member closest to the side peripheral surface. The operation becomes stable.

One embodiment will be described with reference to FIGS.
As shown in FIG. 1, a housing 1 as a stationary member has an end wall 2 at one end.

  An outer ring 3 as an input member is incorporated in the housing 1. The outer ring 3 is rotatably supported by a bearing 4 incorporated in the other end of the housing 1.

  An inner ring 5 as an output member is incorporated inside the outer ring 3, and both wheels 3 and 5 are relatively rotatable by a bearing 6 incorporated between the inner ring 5 and the outer ring 3. Therefore, the outer ring 3 as the input member and the inner ring 5 as the output member are supported coaxially in the housing 1 so as to be rotatable about the axis.

  A wet multi-plate clutch 7 is incorporated between the outer ring 3 and the inner ring 5 so that the rotation transmission can be turned on and off. The wet multi-plate clutch 7 includes a large number of input side clutch plates 8 and a large number of output side clutch plates 9. The input side clutch plate 8 and the output side clutch plate 9 are alternately assembled in the axial direction, and the input side clutch plate 8 is supported with respect to the outer ring 3 so as to be movable in the axial direction. On the other hand, the output side clutch plate 9 is supported by the inner ring 5 so as to be movable in the axial direction.

  The input side clutch plate 8 and the output side clutch plate 9 are moved in the axial direction by a loaded axial force and are brought into close contact with each other to be in a coupled state. By this connection, the rotation of the outer ring 3 can be transmitted to the inner ring 5.

  On one side in the axial direction of the wet multi-plate clutch 7, a clutch control device 10 that controls the coupling and decoupling of the wet multi-plate clutch 7 is provided.

  The clutch control device 10 includes an electromagnetic clutch portion 10A and an axial force load portion 10B that converts the rotational torque of the outer ring 3 into an axial force and loads the wet multi-plate clutch 7 when the electromagnetic clutch portion 10A is coupled.

  The electromagnetic clutch portion 10 </ b> A includes an armature 11, a rotor 12 provided on one side of the armature 11, and an electromagnet 13 provided on one side of the rotor 12.

  The armature 11 is supported rotatably around an output shaft (not shown) connected to the inner ring 5 and is movable in the axial direction.

  The rotor 12 has an outer cylinder part 12b and an inner cylinder part 12a, and a male screw 14 is formed on the outer periphery of the outer cylinder part 12b. The rotor 12 is fixed to the outer ring 3 by screwing a male screw 14 into a female screw 15 formed on the inner periphery of one end of the outer ring 3, and is loosened by tightening a lock nut 16 that is screw-engaged with the female screw 15. A minute gap (air gap) t1 is formed between the rotor 12 and the armature 11, and the gap t1 can be adjusted by adjusting the screwing amount of the rotor 12. Further, a separation spring 18 that urges the armature 11 in a direction away from the rotor 12 is incorporated between the rotor 12 and the armature 11.

  The electromagnet 13 is incorporated in a concave portion of the rotor 12 having a U-shaped cross section, that is, between the outer cylinder portion 12b and the inner cylinder portion 12a. The electromagnet 13 includes an electromagnetic coil 13a and a core 13b that supports the electromagnetic coil 13a. When the electromagnetic coil 13a is energized, a magnetic flux flows through the core 13b, the rotor 12, and the armature 11, and the bottom end face 12c of the rotor 12 is obtained. The armature 11 is adsorbed on the surface. By the adsorption, the armature 11 is coupled to the outer ring 3, and the armature 11 rotates together with the outer ring 3.

  As shown in FIG. 1, the axial force load portion 10 </ b> B is provided with a pressure plate 21 between the armature 11 and the wet multi-plate clutch 7, prevents the pressure plate 21 from rotating around the inner ring 5, and can move in the axial direction. Are provided on each of the opposing surfaces of the pressure plate 21 and the armature 11 so that the groove depth gradually decreases from the center to both ends in the circumferential direction, and a ball 24 is provided between the cam grooves 22 and 23. As a result, the pressure plate 21 is moved toward the wet multi-plate clutch 7 by the relative rotation of the armature 11 with respect to the pressure plate 21, and the wet multi-plate clutch 7 is pushed in the axial direction (FIGS. 2 and 3). reference).

  As shown in FIG. 1, the electromagnet 13 is an elastic body between a retaining ring 20 a attached to an engagement groove 1 a provided on the inner periphery of the housing 1 and a flange 20 that protrudes outward from the electromagnet 13. 20 b is interposed, and due to the elastic force of the elastic body 20 b, the electromagnet 13 has a back surface of the core 13 b covering the electromagnetic coil 13 a, that is, an end surface 13 d opposite to the end surface 13 c facing the contact surface between the rotor 12 and the armature 11. Is fixed to the end wall 2 of the housing 1 by pressing.

The operation of this rotation transmission device will be described. An input shaft is connected to the outer ring 3, and an output shaft is connected to the inner ring 5. In order to connect the input shaft and the output shaft, spline teeth 3a and 5a are provided on the inner circumferences of the outer ring 3 and the inner ring 5, respectively.
FIG. 1 shows a state in which energization is interrupted with respect to the electromagnetic coil 13a of the electromagnet 13, and the wet multi-plate clutch 7 is in a disengaged state. For this reason, even if the outer ring 3 rotates, the rotation is not transmitted to the inner ring 5, and only the outer ring 3 rotates freely.

When the electromagnetic coil 13 a of the electromagnet 13 is energized while the outer ring 3 is rotating, the armature 11 is attracted to the rotor 12, the outer ring 3 and the armature 11 are coupled, and the armature 11 rotates together with the outer ring 3.
Further, the armature 11 rotates relative to the pressure plate 21, and is formed in the cam groove 23 and the pressure plate 21 formed in the armature 11 by the relative rotation as shown in FIGS. 3 (a) to 3 (b). Since the cam groove 22 is out of phase in the circumferential direction, the pressure plate 21 moves in the axial direction toward the wet multi-plate clutch 7 to generate an axial force. Due to the axial force, the input side clutch plate 8 and the output side clutch plate 9 of the wet multi-plate clutch 7 are pressed and moved in the axial direction, and are in close contact with each other.
By this connection, the rotation of the outer ring 3 is transmitted to the inner ring 5 via the wet multi-plate clutch 7, and the inner ring 5 rotates in the same direction as the outer ring 3.

  Here, when the pressure plate 21 presses the wet multi-plate clutch 7 in the axial direction, the armature 11 is pressed against the rotor 12 by the reaction force, so that once the electromagnetic clutch portion 10A is coupled, the subsequent electromagnetic coil Even if the current passed through 13a is reduced, the armature 11 is held in the attracted state, and the current consumption can be reduced.

In a state where rotational torque is transmitted from the outer ring 3 to the inner ring 5, when energization to the electromagnetic coil 13 a is released, the armature 11 is released from adsorption and separated from the rotor 12. When the suction is released, the separation spring 18 presses the armature 11 toward the pressure plate 21 and the pressure plate 21 is pressed from the wet multi-plate clutch 7, so that the cam grooves 22 and 23 press-fit the ball 24. As a result, the armature 11 and the pressure plate 21 rotate relative to each other, and the ball 24 is returned to the neutral position arranged at the center of the cam grooves 22 and 23.
For this reason, the load of the axial force on the wet multi-plate clutch 7 is released, and the wet multi-plate clutch 7 is in a disengaged state, and transmission of rotational torque from the outer ring 3 to the inner ring 5 is interrupted.

In the above-described rotation transmission device that controls the coupling and decoupling of the wet multi-plate clutch 7 by energization and decoupling of the electromagnet 13 with respect to the electromagnetic coil 13a, the contact / separation operation between the armature 11 and the rotor 12 by the electromagnet 13 is unstable If this is the case, when the electromagnetic coil 13a is energized, the armature 11 cannot be held in the attracted state, and the wet multi-plate clutch 7 cannot be coupled.
In particular, when the magnetic field of the electromagnet 13 flows from the rotor 12 through the outer ring 3 to the bearing 4, the clutch plate 8, the clutch plate 9, and the inner ring 5 in this order, the armature 11 is affected by the action of the magnetic field generated by the inner ring 5. Since it is attracted to the end face E side of the inner ring 5, the rotation of the outer ring 3 is not reliably transmitted to the armature 11 and an appropriate axial force may not be applied to the wet multi-plate clutch 7.

  However, in this embodiment, the inner ring 5, which is a member facing the air gap t <b> 1 between the armature 11 and the rotor 12 closest to the surface 11 b opposite to the contact / separation surface 11 a with the rotor 12 of the armature 11. Therefore, the influence of the magnetic field from the inner ring 5 acting on the armature 11 is relatively smaller than the influence of the magnetic field from the rotor 12 side. Therefore, an extremely stable operation of the armature 11 can be obtained, and the wet multi-plate clutch 7 can be reliably controlled by energizing and shutting off the electromagnetic coil 13a.

Similarly, when the gap t3 between the inner peripheral surface F of the outer ring 3 and the side peripheral surface 11c of the armature 11 shown in FIG. 1 is small, there is a problem that the armature 11 is attracted to the outer ring 3 by the action of the magnetic field generated by the outer ring 3. is there.
However, in this embodiment, the air gap t1 between the armature 11 and the rotor 12 is set so that the side surface 11c of the armature 11 and the inner periphery of the outer ring 3 which is a member facing the side surface 11c most closely. Since it is smaller than the gap t3 with the surface F, the influence of the magnetic field from the outer ring 3 side acting on the armature 11 is relatively smaller than the influence of the magnetic field from the rotor 12 side. For this reason, a very stable operation of the armature 11 can be obtained.

In the above embodiment, the member closest to the surface 11b opposite to the contact / separation surface 11a of the armature 11 with the rotor 12 is the end surface E of the inner ring 5 as an output member. The member that is closest to the surface 11b opposite to the contact / separation surface 11a with the rotor 12 of the armature 11 is not limited to this embodiment, and, for example, an input member and an output member are arranged inside out. In this case, it is also conceivable that the end face E of the outer ring is the output member.
Similarly, in the above embodiment, the side peripheral surface 11c of the armature 11 and the member closest to the side peripheral surface 11c are the inner peripheral surface F of the outer ring 3 which is an input member. The member is not limited to the example, and the side peripheral surface 11c of the armature 11 and the member closest to the side peripheral surface 11c are opposed to each other, for example, in the case where the input member and the output member are arranged in the reverse direction as described above. In this case, the inner peripheral surface F of the outer ring which is the output member may be considered.

Vertical front view showing an embodiment of a rotation transmission device according to an example Sectional drawing along the II line of FIG. The principal part expanded sectional view which shows the engagement state of a cam groove and a ball | bowl 1 is an enlarged cross-sectional view of the main part of FIG.

Explanation of symbols

1 Housing 2 End Wall 3 Outer Ring (Input Member)
5 Inner ring (output member)
7 Wet multi-plate clutch 10 Clutch control device 10A Electromagnetic clutch portion 10B Axial force load portion 11 Armature 12 Rotor 13 Electromagnet 13a Electromagnetic coil 13b Core t1 Air gap t2, t3 Gap

Claims (3)

One of the input member 3 and the output member 5 is coaxially arranged inside the other, and the input member 3 and the output member 5 are respectively supported in the housing 1 so as to be rotatable about the axis. The input member 3 and the output member Between the input member 3 and the output member 5 is incorporated with a wet multi-plate clutch 7 between the input member 3 and the wet multi-plate clutch 7. A control device 10 is provided, and the clutch control device 10 contacts and separates the rotor 11 and the armature 12 by energizing and shutting off the electromagnet 13 fixed to the housing 1, and rotational torque of the input member 3 by the contact and separation. In the rotation transmission device that converts the axial force into the wet multi-plate clutch 7 and converts the axial force into the axial force,
The air gap t1 between the armature 11 and the rotor 12 is larger than the gap t2 between the end surface E of the member that is closest to and faces the surface 11b opposite to the contact / separation surface 11a of the armature 11 with the rotor 12. A rotation transmission device characterized by being made smaller. One of the input member 3 and the output member 5 is coaxially arranged inside the other, and the input member 3 and the output member 5 are respectively supported in the housing 1 so as to be rotatable about the axis. The input member 3 and the output member Between the input member 3 and the output member 5 is incorporated with a wet multi-plate clutch 7 between the input member 3 and the wet multi-plate clutch 7. A control device 10 is provided, and the clutch control device 10 contacts and separates the rotor 11 and the armature 12 by energizing and shutting off the electromagnet 13 fixed to the housing 1, and rotational torque of the input member 3 by the contact and separation. In the rotation transmission device that converts the axial force into the wet multi-plate clutch 7 and converts the axial force into the axial force,
The air gap t1 between the armature 11 and the rotor 12 is made smaller than the gap t3 between the side peripheral surface 11c of the armature 11 and the inner peripheral surface F of the member closest to the side peripheral surface 11c. A rotation transmission device characterized by the above.   2. The rotation transmission device according to claim 1, wherein the air gap t <b> 1 is larger than the gap t <b> 3 between the side peripheral surface 11 c of the armature 11 and the inner peripheral surface F of the member that is closest to and faces the side peripheral surface 11 c. A rotation transmission device characterized by being made smaller.

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