JP2019214337A - Free wheel hub - Google Patents

Abstract

To provide a free wheel hub which achieves excellent workability for attaching a permanent magnet to a fixed yoke and in which the permanent magnet has a stable force for suctioning a movable yoke.SOLUTION: A free wheel hub includes: a slide member 33 which is supported so as to be movable in an axial direction between a lock position and a free position; a movable yoke 51 which moves integrally with the slide member 33 in the axial direction; a fixed yoke 50 which is disposed facing the movable yoke 51 in the axial direction; and an annular permanent magnet 52 attached to a surface of the fixed yoke 50 which faces the movable yoke 51 in the axial direction. The free wheel hub is provided with an annular magnet holder 70 which is integrally fixed to the permanent magnet 52 and made of a non-magnetic material. A snap fit claw 73 is formed at the magnet holder 70.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a freewheel hub used for a part-time four-wheel drive vehicle.

  A part-time four-wheel drive vehicle capable of switching between two-wheel drive and four-wheel drive is known. Part-time four-wheel drive vehicles are driven by two-wheel drive that drives only the rear wheels during normal driving, and four-wheel drive that drives both front and rear wheels when driving on rough roads such as snowy roads. It is a vehicle that can travel on.

  In this part-time four-wheel drive vehicle, a freewheel hub is often used as a hub to which front wheels are attached. The free wheel hub is a hub capable of switching between a locked state in which rotation is transmitted between the front axle and the front wheel and a free state in which transmission of rotation between the front axle and the front wheel is blocked. When this freewheel hub is used, it is possible to prevent the transmission of rotation from the front wheels to the axle by reducing the energy loss due to rotation of the axle by setting the freewheel hub to the free state when driving two wheels. Is possible.

  As a freewheel hub, the one described in Patent Document 1 is known. The free wheel hub disclosed in Patent Document 1 is a hub that is supported so as to be rotatable relative to an axle, a lock position that transmits rotation between the axle and the hub, and a free that blocks transmission of rotation between the axle and the hub. A slide member supported so as to be movable in the axial direction between the position, a movable yoke coupled to the slide member so as to move integrally with the slide member in the axial direction, and opposed to the movable yoke in the axial direction. A fixed yoke, a spring that urges the movable yoke in a direction away from the fixed yoke, and an annular permanent magnet attached to an axially opposed surface of the fixed yoke with respect to the movable yoke.

  When the slide member is at the lock position, the slide member is held at the lock position by the urging force of the spring. On the other hand, when the slide member is in the free position, the slide member is held in the free position by the force with which the permanent magnet attracts the movable yoke.

JP 2011-131693 A

  By the way, the conventional freewheel hub as disclosed in Patent Literature 1 uses an adhesive as a method of fixing a permanent magnet to a fixed yoke. That is, the permanent magnet is fixed to the fixed yoke by adhering the axially facing surfaces of the fixed yoke and the annular permanent magnet with an adhesive.

  However, when the permanent magnet is fixed using an adhesive, the operation of bonding the permanent magnet to the fixed yoke is difficult because the permanent magnet and the fixed yoke attract each other. Therefore, there is a problem that the center position of the fixed yoke and the center position of the permanent magnet are likely to be shifted. If the center position of the fixed yoke is shifted from the center position of the permanent magnet, the force with which the permanent magnet attracts the movable yoke becomes unstable. Moreover, since it takes time until the adhesive is solidified, there is also a problem that the assembly cost is high.

  An object of the present invention is to provide a freewheel hub which is excellent in workability for attaching a permanent magnet to a fixed yoke and has a stable force for attracting the movable yoke by the permanent magnet.

In order to solve the above problems, the present invention provides a freewheel hub having the following configuration.
A hub supported to be rotatable relative to the axle;
A slide member supported so as to be movable in the axial direction between a lock position for transmitting rotation between the axle and the hub and a free position for blocking transmission of rotation between the axle and the hub;
A movable yoke coupled to the slide member so as to move integrally with the slide member in the axial direction;
A fixed yoke disposed opposite the movable yoke in the axial direction,
A spring for urging the movable yoke in a direction away from the fixed yoke;
A freewheel hub comprising: an annular permanent magnet attached to an axially facing surface of the fixed yoke with respect to the movable yoke;
An annular magnet holder made of a non-magnetic material fixed integrally to the permanent magnet;
The magnet holder is formed with a snap-fit claw that restricts the relative movement of the fixed yoke relative to the magnet holder by engaging with the fixed yoke.
Freewheel hub characterized by that.

  With this configuration, the permanent magnet is attached to the fixed yoke by engaging the snap fit claw formed on the magnet holder with the fixed yoke, so that the operation of attaching the permanent magnet is easy. Further, since the permanent magnet is fixed to the magnet holder integrally in advance, and the magnet holder is attached to the fixed yoke with a snap-fit claw, the permanent magnet can be fixed to the fixed yoke with stable positional accuracy. Therefore, the force with which the permanent magnet attracts the movable yoke is stabilized. In addition, since the magnet holder is made of a non-magnetic material, it is possible to prevent a magnetic field line from the permanent magnet from being short-circuited through the magnet holder. Therefore, the magnetic field lines can be efficiently concentrated on the fixed yoke and the movable yoke, and the force with which the permanent magnet attracts the movable yoke is large.

  The fixed yoke has an annular plate portion to which the permanent magnet is attached, and an inner cylindrical portion extending from the inner periphery of the annular plate portion to the movable yoke side through the inner diameter side of the permanent magnet, The inner cylinder portion may be configured to receive the movable yoke at an end surface on the movable yoke side.

  In this case, it is preferable that the magnet holder has a fitting cylinder portion that fits between the inner periphery of the permanent magnet and the outer periphery of the inner cylinder portion.

  With this configuration, the fitting cylinder portion of the magnet holder regulates the relative movement in the radial direction between the permanent magnet and the inner cylinder portion of the fixed yoke. The permanent magnet can be mounted in a state where the center position matches. Therefore, the force with which the permanent magnet attracts the movable yoke becomes more stable.

The inner cylinder part employs a claw receiving groove formed in a radial direction through an end of the inner cylinder part on the movable yoke side,
The snap-fit claw includes a claw base portion accommodated in the claw accommodation groove, a claw intermediate portion extending in the axial direction from the claw base portion along the inner circumference of the inner cylinder portion, and a radially outward direction from the claw intermediate portion. It is preferable to adopt a configuration having a claw tip portion that extends to the ring plate and engages with the annular plate portion.

  With this configuration, the claw base of the snap-fit claw is accommodated in the claw accommodating groove formed at the end of the movable yoke side of the inner cylinder portion of the fixed yoke. When the movable yoke is received at the end face, it is possible to prevent the movable yoke from contacting the snap fit claw.

  The magnet holder can be fixed to the permanent magnet by insert molding. That is, the magnet holder can be integrally fixed to the permanent magnet by molding the magnet holder in a state where the permanent magnet is arranged in the molding die of the magnet holder.

The permanent magnet has an axially facing surface with respect to the fixed yoke and an axially facing surface with respect to the movable yoke, and the axially facing surface with respect to the fixed yoke is disposed in contact with the fixed yoke. Adopt
The magnet holder includes an annular plate portion that is in surface contact with a surface of the permanent magnet that faces the movable yoke in the axial direction, and a fitting claw portion provided on an outer periphery of the plate portion. Can be adopted in which the magnet holder is fixed to the permanent magnet by fitting to the outer peripheral surface of the permanent magnet.

  As the non-magnetic material, a resin can be adopted.

  Further, a non-magnetic metal may be employed as the non-magnetic material.

  In the freewheel hub of the present invention, the permanent magnet is attached to the fixed yoke by engaging the snap-fit pawl formed on the magnet holder with the fixed yoke, so that the operation of attaching the permanent magnet is easy. Further, since the permanent magnet is fixed to the magnet holder integrally in advance, and the magnet holder is attached to the fixed yoke with a snap-fit claw, the permanent magnet can be fixed to the fixed yoke with stable positional accuracy. Therefore, the force with which the permanent magnet attracts the movable yoke is stabilized. In addition, since the magnet holder is made of a non-magnetic material, it is possible to prevent a magnetic field line from the permanent magnet from being short-circuited through the magnet holder. Therefore, the magnetic field lines can be efficiently concentrated on the fixed yoke and the movable yoke, and the force with which the permanent magnet attracts the movable yoke is large.

The figure which shows typically the part-time four-wheel drive vehicle in which the freewheel hub of embodiment of this invention is used. Sectional drawing of the freewheel hub of embodiment of this invention FIG. 2 is an enlarged cross-sectional view of the vicinity of the slide member FIG. 3 is an enlarged sectional view in the vicinity of the permanent magnet and the magnet holder in FIG. The figure which shows the state which the slide member of FIG. 3 moved to the lock position from the free position. Sectional drawing which shows the process in which the permanent magnet and magnet holder shown in FIG. 4 are attached to a fixed yoke Perspective view of the permanent magnet and the magnet holder shown in FIG. The perspective view which shows the process in which the permanent magnet and magnet holder shown in FIG. 4 are attached to a fixed yoke. Sectional drawing which shows the modification of the magnet holder shown in FIG. Perspective view of permanent magnet and magnet holder shown in FIG.

  FIG. 1 schematically shows a part-time four-wheel drive vehicle using a freewheel hub 1 according to an embodiment of the present invention. This part-time four-wheel drive vehicle distributes the rotation input from the transmission 3 to the engine 2, the transmission 3 for shifting and outputting the rotation input from the engine 2, and the front propeller shaft 4 and the rear propeller shaft 5. And a transfer 6 for outputting.

  The transfer 6 is a two-wheel drive state in which the rotation input from the transmission 3 is not output to the front propeller shaft 4 but is output only to the rear propeller shaft 5 in response to the operation of the transfer lever 7, and the transfer 3 is input from the transmission 3. And a switching mechanism 8 for switching between a four-wheel drive state in which rotation is output to both the front propeller shaft 4 and the rear propeller shaft 5.

  The rear propeller shaft 5 is connected to a rear differential 9. The rear differential 9 is a differential device that distributes and transmits rotation input from the rear propeller shaft 5 to a pair of left and right axles 10. The pair of left and right axles 10 are connected to the respective rear wheels 11 so as to rotate together with the pair of left and right rear wheels 11 respectively. The front propeller shaft 4 is connected to the front differential 12. The front differential 12 is a differential device that distributes and transmits rotation input from the front propeller shaft 4 to a pair of left and right axles 13. The pair of left and right axles 13 are connected to the pair of left and right front wheels 14 via the freewheel hub 1, respectively.

  When the transfer lever 6 is switched to the four-wheel drive state by operating the transfer lever 7, the freewheel hub 1 switches to a locked state in which rotation is transmitted between the axle 13 and the front wheels 14 in conjunction therewith, and the transfer When the transfer 6 is switched to the two-wheel drive state by the operation of the lever 7, in conjunction with this, the transfer 6 is switched to the free state in which the transmission of rotation between the axle 13 and the front wheels 14 is interrupted. The operation of the freewheel hub 1 is performed by an external operation using electricity or fluid pressure (air pressure in this embodiment).

  As shown in FIG. 2, the freewheel hub 1 includes a cylindrical spindle 20 disposed so as to surround the axle 13, a hub 22 rotatably supported by a rolling bearing 21 mounted on the outer periphery of the spindle 20, and It has a cover 24 fixed to the hub 22 with bolts 23 so as to rotate integrally with the hub 22. Hereinafter, the side close to the center in the vehicle width direction (right side in the figure) and the side far from the center in the vehicle width direction (left side in the figure) along the axial direction of the axle 13 are referred to as the axially inner side and the axially outer side, respectively.

  The spindle 20 is formed in a tubular shape through which the axle 13 is inserted. A bush 25 that rotatably supports the spindle 20 is incorporated between the inner periphery of the spindle 20 and the outer periphery of the axle 13. An oil seal 26 is incorporated between the inner circumference of the axially inner end of the spindle 20 and the outer circumference of the axle 13. The spindle 20 is fixedly attached to a steering knuckle (not shown).

  The hub 22 is supported by a rolling bearing 21 incorporated between the inner periphery of the hub 22 and the outer periphery of the spindle 20 so as to be rotatable relative to the axle 13. The front wheel 14 (see FIG. 1) is fixed to the hub 22. An oil seal 27 is incorporated between the inner periphery of the end of the hub 22 in the axial direction and the outer periphery of the spindle 20.

  The spindle 20 has a first air passage 28 communicating with an annular space formed between the inner periphery of the hub 22 and the outer periphery of the spindle 20, and a first air passage 28 formed between the inner periphery of the spindle 20 and the outer periphery of the axle 13. A second air passage 29 communicating with the annular space is provided. The first air passage 28 and the second air passage 29 are connected to a first air pipe 31 and a second air pipe 32, respectively. The first air pipe 31 and the second air pipe 32 are connected to a negative pressure tank via a solenoid valve (not shown).

  The axle 13 has a portion that protrudes axially outward from the spindle 20, and a slide member 33 is fitted around the outer periphery of the portion. The sliding member 33 and the axle 13 are fitted by spline fitting, whereby the sliding member 33 is supported so as to be movable relative to the axle 13 in the axial direction and not relatively rotatable. A plurality of external teeth 34 arranged at equal pitches in the circumferential direction are formed on the outer periphery of the axially inner portion of the slide member 33.

  The cover 24 has a cover cylinder 35 formed so as to surround a portion of the axle 13 projecting outward from the spindle 20 in the axial direction, and a cover lid 36 for closing an axial outer end of the cover cylinder 35. An oil seal 37, an outer gear 38, and a sleeve 39 are fitted in the inner periphery of the cover cylinder portion 35 in the axial direction. The oil seal 37 is in sliding contact with the outer periphery of the nut member 40 that is screw-engaged with the outer periphery of the axially outer end of the spindle 20. The outer periphery of the outer gear 38 is spline-fitted with the inner periphery of the cover cylinder portion 35, whereby the outer gear 38 is prevented from rotating around the cover 24.

  As shown in FIG. 3, on the inner periphery of the outer gear 38, there are formed inner teeth 41 that mesh with the outer teeth 34 of the slide member 33. A protrusion 43 is formed on the outer periphery of the sleeve 39 to engage with a groove 42 formed on the inner periphery of the cover cylinder portion 35, and the sleeve 39 is prevented from rotating around the cover 24 by the engagement of the protrusion 43 and the groove 42. ing. A space between the axially opposed surfaces of the sleeve 39 and the outer gear 38 is sealed with a seal member 44.

  A connecting member 45 is fitted around the outer periphery of the axially outer end of the slide member 33. The connecting member 45 is in contact with the end surface of the slide member 33 on the outer side in the axial direction and is locked to a circlip 46 attached to the outer periphery of the slide member 33. Thereby, the connection member 45 and the slide member 33 are connected so as to be movable integrally in the axial direction. Further, the inner periphery of the connecting member 45 and the fitting surface of the slide member 33 are cylindrical surfaces that are fitted with a gap, and the connecting member 45 and the slide member 33 are relatively rotatable.

  A fixed yoke 50 is fixed inside the cover lid 36. On the inner side in the axial direction of the fixed yoke 50, a movable yoke 51 is disposed so as to oppose. Both the fixed yoke 50 and the movable yoke 51 are made of a magnetic metal material. The magnetic metal material is, for example, a metal having a relative permeability of 1000 or more, and iron, silicon steel, etc. can be employed. The connecting member 45 is also formed of a magnetic metal material.

  An annular permanent magnet 52 is attached to a surface of the fixed yoke 50 facing the movable yoke 51 in the axial direction. The permanent magnet 52 is magnetized in such a direction that one end face of the both end faces in the axial direction is an N pole and the other end face is an S pole. Between the fixed yoke 50 and the movable yoke 51, a spring 53 that urges the movable yoke 51 in a direction away from the fixed yoke 50 is incorporated. The spring 53 is a compression coil spring formed by winding a wire in a coil shape.

  The movable yoke 51 includes an annular attracting plate 54 axially facing the permanent magnet 52, a spring seat 55 receiving the spring 53 on the outer diameter side of the attracting plate 54, and a spring seat 55 on the outer diameter of the spring seat 55. And a tapered cylindrical portion 56 extending toward the fixed yoke 50. On the outer periphery of the tapered cylindrical portion 56, a rotation preventing projection 58 that is inserted into a through hole 57 formed in the fixed yoke 50 is formed.

  The movable yoke 51 and the connecting member 45 are connected by a rivet 59. Here, the movable yoke 51 and the slide member 33 are connected via a connecting member 45. That is, the movable yoke 51 is coupled to the slide member 33 so as to move integrally with the slide member 33 in the axial direction.

  The inside of the cover 24 includes a first airtight chamber 61 communicating with the first air passage 28 (see FIG. 2) by a diaphragm 60 formed of a flexible material (rubber or the like), and a second air. It is partitioned into a second airtight chamber 62 communicating with the passage 29 (see FIG. 2). The inner peripheral portion of the diaphragm 60 is sandwiched between the movable yoke 51 and the connecting member 45, and the outer peripheral portion of the diaphragm 60 is connected to the sleeve 39.

  The diaphragm 60 functions as a member that drives the slide member 33 in the axial direction. That is, when a negative pressure is introduced from the first air passage 28 to the first hermetic chamber 61, the diaphragm 60 bends outward in the axial direction due to a pressure difference between the first hermetic chamber 61 and the second hermetic chamber 62, and the slide member 33 moves outward in the axial direction. On the other hand, when a negative pressure is introduced from the second air passage 29 to the second hermetic chamber 62, the diaphragm 60 bends inward in the axial direction due to the pressure difference between the first hermetic chamber 61 and the second hermetic chamber 62, and the slide member 33 moves inward in the axial direction.

  The slide member 33 has a lock position (see FIG. 5) for transmitting rotation between the axle 13 and the hub 22 by engaging the outer teeth 34 on the outer periphery with the inner teeth 41 of the outer gear 38. By disengaging the inner gear 41 from the inner gear 41 of the outer gear 38, it is possible to move axially between a free position (see FIG. 3) where transmission of rotation between the axle 13 and the hub 22 is interrupted. .

  As shown in FIG. 4, the fixed yoke 50 includes an annular plate portion 63 having an axially facing surface with respect to the movable yoke 51, and a movable yoke passing from the inner periphery of the annular plate portion 63 to the inner diameter side of the permanent magnet 52. And an inner cylindrical portion 64 extending toward the side of the movable yoke 51. The end surface of the inner cylindrical portion 64 on the side of the movable yoke 51 receives the movable yoke 51. The inner cylinder portion 64 is formed with a claw receiving groove 65 that penetrates the end portion of the inner cylinder portion 64 on the movable yoke 51 side in the radial direction.

  The permanent magnet 52 is integrally fixed to an annular magnet holder 70. The permanent magnet 52 has an axially facing surface 71 with respect to the fixed yoke 50 and an axially facing surface 72 with respect to the movable yoke 51, and the axially facing surface 71 with respect to the fixed yoke 50 is disposed in contact with the fixed yoke 50. . The magnet holder 70 is made of resin as a nonmagnetic material. A nonmagnetic metal may be adopted as the nonmagnetic material. The nonmagnetic metal is, for example, a metal having a relative permeability of 100 or less, and aluminum or the like can be adopted.

  The magnet holder 70 is formed with a snap-fit claw 73 that engages with the fixed yoke 50 to restrict the fixed yoke 50 from moving relative to the magnet holder 70 in the axial direction. A plurality of snap fit claws 73 are formed at intervals in the circumferential direction (see FIG. 7). The snap fit claw 73 includes a claw base portion 74 accommodated in the claw accommodation groove 65, a claw intermediate portion 75 extending in the axial direction from the claw base portion 74 along the inner periphery of the inner cylinder portion 64, and the claw intermediate portion 75. A claw tip 76 that extends outward in the radial direction and engages with the annular plate 63. In addition, the magnet holder 70 has a fitting cylinder part 77 that fits between the inner circumference of the permanent magnet 52 and the outer circumference of the inner cylinder part 64.

  The magnet holder 70 is fixed to the permanent magnet 52 by insert molding. That is, the magnet holder 70 is integrally fixed to the permanent magnet 52 by molding the magnet holder 70 in a state where the permanent magnet 52 is disposed in the molding die of the magnet holder 70.

  When the vehicle shown in FIG. 1 travels in a four-wheel drive state, the freewheel hub 1 introduces a negative pressure from the second air passage 29 shown in FIG. As shown in FIG. 5, the slide member 33 is driven inward in the axial direction, and is moved to a lock position where the outer teeth 34 of the slide member 33 engage with the inner teeth 41 of the outer gear 38. As a result, rotation is transmitted from the axle 13 shown in FIG. 1 to the front wheels 14, and it is possible to travel by four-wheel drive that drives both the front wheels 14 and the rear wheels 11. Here, as shown in FIG. 5, when the slide member 33 is in the locked position, the slide member 33 is held in the locked position by the urging force of the spring 53.

  On the other hand, when the vehicle shown in FIG. 1 travels in the two-wheel drive state, a negative pressure is introduced from the first air passage 28 shown in FIG. 2 to the first hermetic chamber 61, as shown in FIG. Then, the slide member 33 is driven axially outward to move to a free position where the engagement between the external teeth 34 of the slide member 33 and the internal teeth 41 of the outer gear 38 is released. Thereby, it is possible to prevent the rotation from being transmitted from the front wheel 14 shown in FIG. 1 to the axle 13 and to reduce energy loss due to the axle 13 and the front propeller shaft 4 rotating. Here, as shown in FIG. 3, when the slide member 33 is in the free position, the slide member 33 is held in the free position by the force with which the permanent magnet 52 attracts the movable yoke 51.

  The permanent magnet 52 of the freewheel hub 1 can be attached to the fixed yoke 50 as follows. First, as shown in FIGS. 6 and 8, a permanent magnet 52 integrally fixed to a magnet holder 70 and a fixed yoke 50 are prepared and arranged to face each other in the axial direction. Next, the snap fit claw 73 of the magnet holder 70 is inserted into the inner cylindrical portion 64 of the fixed yoke 50 while being elastically deformed toward the inner diameter side. Then, when the claw tip portion 76 of the snap fit claw 73 passes through the inner cylinder portion 64, the snap fit claw 73 is elastically restored, and the claw tip portion 76 becomes the annular plate portion 63 of the fixed yoke 50 as shown in FIG. It is locked to the outer edge of the inner circumference in the axial direction.

  The freewheel hub 1 attaches the permanent magnet 52 to the fixed yoke 50 by engaging the snap fit claw 73 formed on the magnet holder 70 with the fixed yoke 50. The mounting work of the permanent magnet 52 is easier than the case where the axially opposed surfaces of the magnet 52 are bonded with an adhesive.

  Further, in this freewheel hub 1, the permanent magnet 52 is fixed to the magnet holder 70 in advance and the magnet holder 70 is attached to the fixed yoke 50 with the snap fit claw 73, so that the permanent magnet 52 is fixed with stable positional accuracy. It can be fixed to the yoke 50. Therefore, the force with which the permanent magnet 52 attracts the movable yoke 51 becomes stable.

  In addition, since the magnet holder 70 is formed of a non-magnetic material, it is possible to prevent the magnetic field lines coming out of the permanent magnets 52 from being short-circuited through the magnet holder 70. Therefore, the lines of magnetic force can be efficiently concentrated on the fixed yoke 50 and the movable yoke 51, and the force by which the permanent magnet 52 attracts the movable yoke 51 is large.

  In this freewheel hub 1, as shown in FIG. 4, the fitting cylinder 77 of the magnet holder 70 restricts the relative movement in the radial direction between the permanent magnet 52 and the inner cylinder 64 of the fixed yoke 50. Therefore, the permanent magnet 52 can be mounted in a state where the center position of the permanent magnet 52 and the center position of the inner cylindrical portion 64 of the fixed yoke 50 match, and the permanent magnet 52 and the inner cylindrical portion 64 of the fixed yoke 50 High coaxiality. Therefore, the force with which the permanent magnet 52 attracts the movable yoke 51 becomes more stable.

  Further, since the freewheel hub 1 accommodates the claw base 74 of the snap-fit claw 73 in the claw accommodating groove 65 formed at the end of the inner cylinder portion 64 of the fixed yoke 50 on the movable yoke 51 side. When the movable yoke 51 is received by the end surface of the inner cylinder portion 64 on the side of the movable yoke 51, the movable yoke 51 can be prevented from contacting the snap fit claw 73.

  9 and 10 show modifications of the magnet holder 70. FIG. Portions corresponding to the above embodiment are denoted by the same reference numerals and description thereof is omitted. The magnet holder 70 has an annular plate portion 78 that comes into surface contact with the axially facing surface 72 of the permanent magnet 52 with respect to the movable yoke 51, and a fitting claw portion 79 provided on the outer periphery of the plate portion 78. The magnet holder 70 is fixed to the permanent magnet 52 by fitting the fitting claw portion 79 to the outer peripheral surface of the permanent magnet 52.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

Reference Signs List 1 freewheel hub 13 axle 22 hub 33 slide member 50 fixed yoke 51 movable yoke 52 permanent magnet 53 spring 63 annular plate portion 64 inner cylinder portion 65 claw receiving groove 70 magnet holder 71 axial facing surface 72 axial facing surface 73 snap Fitting claw 74 Claw base 75 Claw middle 76 Claw tip 77 Fitting cylinder 78 Plate 79 Fitting claw

Claims (8)

A hub (22) supported to be rotatable relative to the axle (13);
Axial direction between a lock position for transmitting rotation between the axle (13) and the hub (22) and a free position for blocking transmission of rotation between the axle (13) and the hub (22) A slide member (33) movably supported by
A movable yoke (51) coupled to the slide member (33) so as to move integrally with the slide member (33) in the axial direction;
A fixed yoke (50) disposed axially facing the movable yoke (51);
A spring (53) for biasing the movable yoke (51) in a direction away from the fixed yoke (50);
A freewheel hub comprising: an annular permanent magnet (52) attached to an axially facing surface of the fixed yoke (50) with respect to the movable yoke (51);
An annular magnet holder (70) made of a non-magnetic material fixed integrally to the permanent magnet (52);
The magnet holder (70) is formed with a snap-fit claw (73) that engages with the fixed yoke (50) to restrict the relative movement of the fixed yoke (50) in the axial direction with respect to the magnet holder (70). ing,
Freewheel hub characterized by that.   The fixed yoke (50) passes through an annular plate (63) to which the permanent magnet (52) is attached, and an inner periphery of the annular plate (63) through the inner diameter side of the permanent magnet (52). An inner cylindrical portion (64) extending toward the movable yoke (51), so that the end surface of the inner cylindrical portion (64) on the movable yoke (51) side receives the movable yoke (51). The freewheel hub according to claim 1, wherein the hub is configured.   The free magnet according to claim 2, wherein the magnet holder (70) has a fitting cylinder (77) fitted between an inner periphery of the permanent magnet (52) and an outer periphery of the inner cylinder (64). Wheel hub. The inner cylinder part (64) is formed with a claw receiving groove (65) that penetrates the end of the inner cylinder part (64) on the movable yoke (51) side in the radial direction,
The snap-fit claw (73) includes a claw base (74) accommodated in the claw accommodation groove (65), and an axial direction from the claw base (74) along the inner periphery of the inner cylinder part (64). A claw intermediate portion (75) that extends, and a claw tip portion (76) that extends radially outward from the claw intermediate portion (75) and engages with the annular plate portion (63),
The freewheel hub according to claim 2 or 3.   The freewheel hub according to any one of claims 1 to 4, wherein the magnet holder (70) is fixed to the permanent magnet (52) by insert molding. The permanent magnet (52) has an axial facing surface (71) with respect to the fixed yoke (50) and an axial facing surface (72) with respect to the movable yoke (51), and the shaft with respect to the fixed yoke (50). The direction facing surface (71) is disposed in contact with the fixed yoke (50),
The magnet holder (70) includes an annular plate portion (78) in surface contact with an axially facing surface (72) of the permanent magnet (52) with respect to the movable yoke (51), and an outer periphery of the plate portion (78). A fitting claw portion (79) provided on the outer periphery of the permanent magnet (52) so that the magnet holder (70) is fitted to the permanent magnet. (52),
The freewheel hub according to any one of claims 1 to 4.   The freewheel hub according to any one of claims 1 to 6, wherein the nonmagnetic material is a resin.   The freewheel hub according to any one of claims 1 to 6, wherein the nonmagnetic material is a nonmagnetic metal.

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