WO2019240026A1

WO2019240026A1 - Freewheel hub

Info

Publication number: WO2019240026A1
Application number: PCT/JP2019/022694
Authority: WO
Inventors: 佐藤　光司
Original assignee: Ntn株式会社
Priority date: 2018-06-14
Filing date: 2019-06-07
Publication date: 2019-12-19
Also published as: JP2019214337A

Abstract

Provided is a freewheel hub, comprising a slide member (33) that is supported so as to be movable in an axial direction between a lock position and a free position, a movable yoke (51) that moves integrally with the slide member (33) in the axial direction, a fixed yoke (50) disposed so as to face the movable yoke (51) in the axial direction, and an annular permanent magnet (52) attached to an axially facing surface of the fixed yoke (50) that faces the movable yoke (51), wherein an annular magnet holder (70) made of a non-magnetic material that is fixed integrally with the permanent magnet (52) is provided, and a snap-fit claw (73) is formed on the magnet holder (70).

Description

Freewheel hub

This invention relates to a freewheel hub used in a part-time four-wheel drive vehicle.

A part-time four-wheel drive vehicle that can switch 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 free wheel hub is often used as a hub to which a front wheel is 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.

The thing of patent document 1 is known as a freewheel hub. 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.

This free wheel hub is held in the locked position by the biasing force of the spring when the sliding member is in the locked position. 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 2011-131893 A

By the way, the conventional freewheel hub like patent document 1 used the adhesive agent 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 permanent magnet and the fixed yoke are attracted to each other, so that it is difficult to bond the permanent magnet to the fixed yoke. 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.

The problem to be solved by the present invention is to provide a freewheel hub that is excellent in workability for attaching a permanent magnet to a fixed yoke and has a stable force for the permanent magnet to attract the movable yoke.

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 to 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.

In this case, the permanent magnet is attached to the fixed yoke by engaging the snap fit claws formed on the magnet holder with the fixed yoke, so that the permanent magnet can be easily attached. In addition, 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 cylinder 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, A configuration in which the movable yoke is received by the end surface of the inner cylinder portion on the movable yoke side can be employed.

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

In this way, the fitting cylinder part of the magnet holder restricts the relative movement in the radial direction between the permanent magnet and the inner cylinder part of the fixed yoke, so that the center position of the permanent magnet and the inner cylinder part of the fixed yoke are The permanent magnet can be attached 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.

In this way, the claw base portion of the snap fit claw is accommodated in the claw accommodating groove formed at the end of the inner cylinder portion of the fixed yoke on the movable yoke side. When the movable yoke is received at the end face, the movable yoke can be prevented from coming into contact with the snap fit claws.

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 an axially opposed surface of the permanent magnet with respect to the movable yoke, and a fitting claw portion provided on an outer periphery of the plate portion, and the fitting claw portion. It is possible to adopt a configuration in which the magnet holder is fixed to the permanent magnet by being fitted to the outer peripheral surface of the permanent magnet.

Resin can be used as the non-magnetic material.

Further, a nonmagnetic metal may be employed as the nonmagnetic material.

In the freewheel hub of the present invention, the permanent magnet is attached to the fixed yoke by engaging the snap fit claws formed on the magnet holder with the fixed yoke, so that the permanent magnet can be easily attached. 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 permanent magnet and 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 in which a freewheel hub 1 according to an embodiment of the present invention is used. In this part-time four-wheel drive vehicle, the engine 2, the transmission 3 that shifts and outputs the rotation input from the engine 2, and the rotation that is input from the transmission 3 are distributed to the front propeller shaft 4 and the rear propeller shaft 5. And a transfer 6 for output.

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

The rear propeller shaft 5 is connected to the 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 6 is switched to the four-wheel drive state by operating the transfer lever 7, the freewheel hub 1 is switched to a locked state in which rotation is transmitted between the axle 13 and the front wheel 14 in conjunction with this. When the transfer 6 is switched to the two-wheel drive state by the operation of the lever 7, the operation is performed so as to switch to the free state in which the transmission of rotation between the axle 13 and the front wheel 14 is cut off in conjunction with this. The operation of the freewheel hub 1 is performed by an external operation using electric or fluid pressure (air pressure in this embodiment).

As shown in FIG. 2, the freewheel hub 1 includes a cylindrical spindle 20 arranged so as to surround the axle 13, a hub 22 rotatably supported by a rolling bearing 21 attached to the outer periphery of the spindle 20, A cover 24 fixed to the hub 22 with bolts 23 so as to rotate integrally with the hub 22 is provided. 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 cylindrical 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 a rolling bearing 21 incorporated between the inner periphery of the hub 22 and the outer periphery of the spindle 20 and is supported 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 is formed between 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 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 protruding outward in the axial direction from the spindle 20, and a slide member 33 is fitted to 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 includes a cover cylinder portion 35 formed so as to surround a portion of the axle 13 that protrudes axially outward from the spindle 20, and a cover lid portion 36 that closes an axial outer end of the cover cylinder portion 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, inner teeth 41 that mesh with the outer teeth 34 of the slide member 33 are formed on the inner periphery of the outer gear 38. 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.

The connecting member 45 is fitted to the outer periphery of the end of the slide member 33 in the axial direction. 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 portion 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 made of a magnetic metal material.

An annular permanent magnet 52 is attached to the 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 suction plate portion 54 facing the permanent magnet 52 in the axial direction, a spring seat portion 55 that receives a spring 53 on the outer diameter side of the suction plate portion 54, and an outer diameter side of the spring seat portion 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 coupled 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) and a second air by a diaphragm 60 formed of a flexible material (rubber or the like). It is partitioned into a second hermetic 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) that transmits rotation between the axle 13 and the hub 22, and the external teeth 34 when the external teeth 34 on the outer periphery mesh with the internal teeth 41 of the outer gear 38. And the inner gear 41 of the outer gear 38 are disengaged from each other, so that it can move in the axial direction between a free position (see FIG. 3) that interrupts transmission of rotation between the axle 13 and the hub 22. .

As shown in FIG. 4, the fixed yoke 50 includes an annular plate portion 63 having an axially opposed surface with respect to the movable yoke 51, and a movable yoke passing from the inner periphery of the annular plate portion 63 through the inner diameter side of the permanent magnet 52. The inner cylinder portion 64 extends toward the 51 side, and is configured to receive the movable yoke 51 on the end surface of the inner cylinder portion 64 on the movable yoke 51 side. 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 the 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 relative movement of the fixed yoke 50 in the axial direction with respect to the magnet holder 70. 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 into the second airtight chamber 62 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 moved to a lock position where the external teeth 34 of the slide member 33 engage with the internal 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 a two-wheel drive state, a negative pressure is introduced into the first airtight chamber 61 from the first air passage 28 shown in FIG. Then, the slide member 33 is driven outward in the axial direction and moved to a free position where the external teeth 34 of the slide member 33 and the internal teeth 41 of the outer gear 38 are disengaged. 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.

In the free wheel hub 1 described above, the permanent magnet 52 is attached to the fixed yoke 50 by engaging the snap fit claws 73 formed on the magnet holder 70 with the fixed yoke 50. Compared to the case where the opposing surfaces of the magnet 52 in the axial direction are bonded with an adhesive, the attaching operation of the permanent magnet 52 is easier.

In the freewheel hub 1, the permanent magnet 52 is fixed to the magnet holder 70 integrally in advance, and the magnet holder 70 is attached to the fixed yoke 50 with the snap-fitting claw 73. It can be fixed to the yoke 50. Therefore, the force with which the permanent magnet 52 attracts the movable yoke 51 becomes stable.

Moreover, since the magnet holder 70 is made of a nonmagnetic material, it is possible to prevent the magnetic lines of force from the permanent magnet 52 from being short-circuited through the magnet holder 70. Therefore, the magnetic lines of force can be efficiently concentrated on the fixed yoke 50 and the movable yoke 51, and the force with which the permanent magnet 52 attracts the movable yoke 51 is large.

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

Further, the free wheel hub 1 accommodates the claw base 74 of the snap fit claw 73 in a claw accommodation groove 65 formed at the end of the inner cylinder 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 movable yoke 51 side, the movable yoke 51 can be prevented from coming into contact with the snap fit claws 73.

9 and 10 show a modification 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.

DESCRIPTION OF SYMBOLS 1 Freewheel hub 13 Axle 22 Hub 33 Slide member 50 Fixed yoke 51 Movable yoke 52 Permanent magnet 53 Spring 63 Ring plate part 64 Inner cylinder part 65 Claw accommodating groove 70 Magnet holder 71 Axial facing surface 72 Axial facing surface 73 Snap Fit claw 74 Claw base 75 Claw intermediate part 76 Claw tip part 77 Fitting cylinder part 78 Plate part 79 Fitting claw part

Claims

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 opposite 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 portion (63) to which the permanent magnet (52) is attached, and from the inner periphery of the annular plate portion (63) to the inner diameter side of the permanent magnet (52). An inner cylinder portion (64) extending toward the movable yoke (51), and receiving the movable yoke (51) at an end surface of the inner cylinder portion (64) on the movable yoke (51) side. The freewheel hub according to claim 1, wherein the freewheel hub is configured.
The said magnet holder (70) has the fitting cylinder part (77) fitted between the inner periphery of the said permanent magnet (52), and the outer periphery of the said inner cylinder part (64), The free of Claim 2 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 free wheel 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 free wheel 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.