JP2568194B2 - Hub clutch - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention always generates a sufficient braking force at the time of shifting to a locked state in a four-wheel drive vehicle to improve response, and after locking, it becomes a rotary system component. The present invention relates to a hub clutch that can reduce sliding between fixed parts and improve the durability of brakes and the like.

[Conventional technology]

As a conventional automatic freewheel hub clutch (hereinafter referred to as hub clutch), US Pat. No. 4,327,82
There is one disclosed in No. 1. This hub clutch is composed of a group of rotating parts that are sequentially assembled on the outer periphery of the drive shaft and a stationary part that is assembled on the spindle.The rotating system parts are linked when the drive shaft starts rotating. While starting the operation, the drive shaft and the wheel hub are connected (locked). The rotary system component group and the fixed system component are linked by a fixed system brake member and a rotary system brake member (brake shoe), and these brake members maintain the connection state between the drive shaft and the wheel hub. Brake shoes
It is in sliding contact with the outer peripheral surface of the stationary brake member, and is constantly pressed against the stationary brake member with a predetermined force by a ring-shaped spring.

[Problems to be solved by the invention]

However, in the hub clutch, since the pressure contact force applied by the spring to the sliding portion between the two brake members is always constant even in the locked state, a strong frictional resistance is generated between the two brake members during traveling. I am letting you. Due to such unnecessary frictional resistance, there is a drawback in that durability is significantly deteriorated.

[Means for solving problems]

The present invention has been made in view of the above, and in the process of transitioning to the lock state, the braking of the rotary system brake member by the fixed system brake member is ensured to improve the responsiveness, while the transition to the lock state is completed. After that, in order to prevent the decrease in durability due to unnecessary frictional resistance by releasing the pressure contact with the fixed brake member by the rotating brake member,
An intermediate brake member is disposed between the fixed brake member and the rotary brake member, and the rotary brake member is braked by pressing the intermediate brake member by the operating piece of the rotary brake member to realize locking. Alternatively, the present invention provides a hub clutch adapted to release braking of a rotary brake member.

〔Example〕

Hereinafter, the hub clutch of the present invention will be described in detail.

1 (a) (b) to FIG. 3 are configuration explanatory views of an embodiment of the present invention. This hub clutch is fixedly splined on the outer circumference of the front end of the axle shaft 1 and clutched on the outer circumference. A drive gear 2 having a gear portion 2a and a spline portion 2b is spline-coupled to the spline portion 2b so as to be movable in the axial direction, and a V-protruding cam portion 4a is projectingly formed on an axially inner end edge. The cam member 4 and a V-groove type cam portion 8a, which is prevented from rotating by a fixed system (consisting of a spindle 5 and a lock nut, etc.) and is fitted to the thick portion on the outer diameter side of the cam portion 4a of the cam member 4, is a shaft. A plurality of brake outers 8 on the outer edge in the axial direction, and a cam portion 4a on the outer edge in the axial direction.
V-shaped groove-shaped first cam portion 9a into which the thick portion on the inner diameter side is fitted
And a second cam portion 9b located on both sides of the first cam portion 9a, a brake inner 9 fixed to the outer periphery of the drive gear 2 by a circlip 12, and a claw portion 9a of an inner diameter portion and a later-described portion. A release plate 11 engageable with a claw portion 16b of the intermediate brake member 16, and an axially inner end portion of the brake inner 9 and an axially outer surface of the brake outer 8 are disposed via a thrust bearing 13. Circular clip (C-ring) 1 that is a donut disk-type thrust washer 14 and is engaged between the outer peripheral surface of the brake inner 9 and the inner peripheral surface of the brake outer 8 to unitize both brake members 8 and 9
5, an intermediate brake member having an outer peripheral surface disposed between the thrust washer 14 and the brake inner 9 and having a tapered surface for generating a braking force by sliding on the inner peripheral surface of the brake outer 8.
16 and a spline 22 fixed to the wheel hub (not shown) with bolts 20 on the inner peripheral surface and the end surface has an opening.
A slide having a case 24 that is 23, a spline 25a that engages with a spline portion 22 of the case 24 in an axially movable manner on the outer periphery, and a gear portion 2a of the drive gear and a gear portion 25b that turns the clutch on and off on the inner periphery. Gear 25 and retainer arm 26, which is prevented from rotating by spline 22.
a and the retainer arm 26a, the retainer 26 having an inwardly bent portion 26b on the inner side in the axial direction, the return spring 27 stretched between the step portion 2c on the outer periphery of the drive gear 2 and the spring holder 32, and the retainer. And a shift spring 28 which is stretched between the inner wall surface of the slide gear 25 in the axial direction and biases the slide gear 25 outward in the axial direction (clutch-on direction). Reference numeral 33 is a spindle washer, and 34 is a circlip, which prevents the thrust washer 14 and the like from falling off. The circlip 12 is fitted on the outer peripheral surface of the drive gear 2 and prevents the members (4, 11, 27, etc.) held on the outer periphery of the drive gear 2 from falling off during subassembly.

The return spring 27 is configured to have a spreading force stronger than that of the shift spring 28. A knob 30 is manually rotatably attached to the opening 23 of the case 24, and a boss portion 31 is projectingly formed on the inner center of the knob 30. Reference numeral 40 is a check mechanism composed of a check spring and a ball held in the hole 41 of the knob, and 43 is an oil seal. The tip of the drive gear 2 projects from the axle shaft 1, and the inner periphery is supported by the tip member 1a fixed to the tip of the axle shaft 1.
A bearing 29 is attached between the outer peripheral surface of the tip member 1a and the inner peripheral surface of the boss portion 31 of the knob. The release plate 11 is
It is arranged so as to project on the outer periphery of the drive gear, and the arm
11a has a positional relationship capable of engaging with the projection 9d inside the brake inner and the claw portion 16b of the intermediate brake member 16.

The intermediate brake member 16 is capable of sliding contact with the inner peripheral surface of the brake outer 8 on the brake surface on the outer peripheral surface, and at the pair of taper portions 16a (180 ° intervals) provided on the inner peripheral surface, the brake inner member 9 is provided. It is configured to be engageable with a V-shaped servo cam portion (operating piece) 9e protruding inward in the axial direction.

The axially outer end of the retainer arm 26a of the retainer 26 is bent toward the inner diameter side to form a claw portion 26c, as shown in FIG. 1 (a). A cam surface is formed on the outer peripheral surface of the boss portion 31. The cam surface is a surface that is continuously inclined from the inner side to the outer side in the axial direction, and is configured such that the claw portion 26c of the retainer 26 can be engaged with the cam surface. The inside of the cam surface in the axial direction is the claw
26c is released so that it can enter and leave, and a recess as a lock position is formed on the outer side in the axial direction of the cam surface. The pawl portion of the retainer 26 is rotated by rotating the knob 30.
When the 26c moves axially inward along the cam surface and the claw portion 26c is disengaged from the cam surface, the automatic state is set,
The manual lock state is achieved when the claw portion 26c moves axially outward along the cam surface and is locked at the lock position.

In the above configuration, when the claw portion 26c of the retainer 26 is moved inward in the axial direction along the cam surface by the turning operation of the knob 30, the claw portion 26c is disengaged from the cam surface.
The automatic state shown in the figure is set, and the manual lock state is set when the claw portion 26c moves axially outward along the cam surface and is locked at the lock position.

Since the driving force is not transmitted to the axle shaft 1 during the free running (during two-wheel running) of FIG. 1 (a), and the gear portions 2a and 25b are in the clutch-off (non-meshing) state,
The case 24 side rotates in the free state.

Next, the operation for shifting from the clutch-off state shown in FIGS. 1 (a) and (b) to FIGS. 2 (a) and (b) to the clutch-on state shown in FIGS. 2 (c) and (d) will be described. . First, when the driving force from the engine is transmitted to the axle shaft 1, the drive gear 2 and the cam member 4 start integral rotation. At this time, the cam portion 4a of the cam member 4 is simultaneously fitted in the cam groove 8a of the brake outer 8 and the groove-shaped cam portion 9a of the brake inner 9, but the brake outer 8 which is a fixed system.
The cam member 4 is moved outward in the axial direction by a reaction force that presses the brakes 8 and 9 inward in the axial direction by the thrust force generated at the contact portion with the cam groove 8a. Cam part 4a of cam member 4
Moves axially outward along the groove-shaped cam portion 8a of the brake outer 8, and when it has climbed up the groove 8a, this time it hits the second cam portion 9b of the brake inner 9. At this time, the brake inner 9
Is rotated by the cam member 4, the servo cam portion (operating piece) 9e of the brake inner 9 is the intermediate brake member 16
Although an attempt is made to engage with the inner peripheral taper portion 16a to rotate it, the intermediate brake member 16 causes the inner peripheral surface of the brake outer 8 by the axial inward thrust force generated at the contact portion with the servo cam portion 9e. It is pressed against the surface and rotation is suppressed. As a result of the rotation of the intermediate brake member 16 being suppressed, the rotation of the brake inner 9 is also suppressed, so that the cam portion 4a of the cam member 4 climbs the second cam portion 9b of the brake inner 9 and moves axially outward. Move on. Subsequently, when the cam portion 4a climbs up the second cam portion 9b, the arm 11a of the release plate 11 engages with the protrusion 9d of the brake inner 9 and the taper portion 16a of the intermediate brake member 16 to force it. To rotate,
The intermediate brake member 16 and the brake inner 9 are disengaged from the brake outer 8 and start rotating together with the cam member 4.

When the return spring 27 is bent by the movement of the cam member 4 in the axially outward direction, the slide gear 25 is displaced in the axially outward direction by the shift spring 28, and the gear portion 25a.
And the gear portion 2a are completely meshed with each other (Fig. 2 (c)). When the clutch is completely engaged in this way, the arm 11a of the release plate engages with the protrusion 9d on the inner circumference of the brake inner 9 and the claw portion 16b of the intermediate brake member to engage the brake inner 9 with each other.
Also, the rotation torque is transmitted by directly turning the intermediate brake member 16. At this time, since the axial inner end of the servo cam portion 9e of the brake inner 9 is positioned on the brake outer 8 via the thrust washer 14 and the thrust bearing 18, the return spring is locked when locked (four-wheel drive mode). The expansion force of 27 prevents the intermediate brake member 16 from being pressed against the brake outer 8 in the axial direction, so that no frictional resistance is generated between the fixed brake member 8 and the rotary brake member 9.

Next, when changing from the four-wheel drive state to the two-wheel drive state, if the transmission of the driving force to the axle shaft 1 is interrupted and the vehicle body is slightly moved in the direction opposite to the traveling direction up to now,
The arm 11a of the release plate 11 is connected to the intermediate brake member 16
Of the intermediate brake member 16 away from the claw portion 16b of the
Is about to be turned by the servo cam portion 9e of the brake inner 9 again. Therefore, the intermediate brake member 16 is pressed against the brake outer 8 to be braked. The brake inner 9 is an intermediate brake member as in the transition from free to lock.
Since the rotation is suppressed by 16, the cam portion of the cam member 4
4a moves axially inward along the second cam portion 9b. At this time, the expanding force of the return spring 27 facilitates the cam member 4 to be displaced inward in the axial direction, and finally falls into the cam portion 8a of the brake outer 8 and the cam portion 9a of the brake inner 9. In this way, the clutch-off state is realized. In the process of axially inward displacement of the cam member 4, the gear portion 25b of the slide gear 25 is disengaged from the gear portion 4a.

4 (a) (b) (c) (d) through FIG. 9 (a)
(B) is a configuration explanatory view of the second embodiment of the present invention, the same parts as those of the first embodiment are represented by the same reference numerals, and the duplicated description will be omitted. The difference is that it uses a wire brake 17 of the type. As a result of using the wire brake 17, the brake inner 9 serves as an actuating piece, and instead of the servo cam, the engaged ends 17a and 17b at the pair of ends of the wire brake are engaged.
An engaging projection 9f that can be engaged with is projectingly provided on one end surface.

In the above configuration, in the free (two-wheel drive) state, each member is in the state shown in FIGS. 4 (a) to 4 (d). That is, the cam portion 4a of the cam member 4 has fallen into the cam portions 8a and 9a, and the engagement protrusion (operating piece) 9f of the brake inner 9 does not engage with the engaged ends 17a and 17b of the wire brake 17. It is in the engaged state.

When the transfer is switched to start the rotation of the axle shaft 1 in order to switch from the two-wheel drive mode to the four-wheel drive mode, the drive gear 2 and the cam member 4 rotate integrally, and the cam member 4a of the cam member 4 rotates. The groove-shaped cam portion 8a and the first cam portion 9a of the brake inner 9 move axially outward (FIGS. 5 (a) and 5 (b)). When the brake inner 9 starts to be rotated by the cam member 4 due to the contact of the cam portion 4a with the second cam portion 9b, the engagement protrusion 9f of the brake inner is engaged with the one engaged end portion 17b (or the other end portion 17b) of the wire brake 17. Since the wire brake 17 is engaged with the wire 17a to rotate the wire 17a, the wire brake 17 is expanded and pressure-bonded to the brake outer 8 to generate a large rotation resistance. Therefore, the rotation of the brake inner 9 is suppressed, and the cam portion 4a further climbs the second cam portion 9b of the brake inner. The cam portion 4a further climbs up the second cam portion 9b of the brake inner as shown in FIG. 6 (a). The cam part 4a is shown in FIG. 6 (a).
When the second cam portion 9b of the brake inner has been climbed up like this, the arm 11a of the release plate 11 engages with the other engaged end portion 17a of the wire brake 17 and tries to rotate it. Therefore, the wire brake 17 contracts,
Rotational resistance with the brake outer 8 is reduced. The wire brake 17 is integrally rotated by the release plate 11 together with the brake inner 9. When the cam portion 4a has climbed up the second cam portion 9b of the brake inner, the spline 25b of the slide gear becomes the spline 2 of the drive gear 2.
Completely meshes with a and the locked state is realized. Since the locking portion 9g of the brake inner 9 is positioned on the brake outer 8 via the thrust washer 14 and the thrust bearing 13, it is fixed to the rotary member group (cam member 4, brake inner 9, wire brake 17, etc.). The system brake member 8 is
As in the first embodiment, the extremely weak sliding state in which the thrust force is not generated, the resistance due to the relative rotation between the two is sufficiently eliminated, and there is no fear of causing inconvenience such as deterioration of durability.

When shifting from four-wheel drive to two-wheel drive, transmission of drive force to the axle shaft 1 is interrupted, and the vehicle body is slightly moved in a direction opposite to the traveling direction up to now. Then, the arm 11a of the release plate 11 separates from the engaged end portion 17a or 17b of the wire brake 17,
The wire brake 17 is again pressed in the rotation direction by the engagement protrusion 9f of the brake inner, and is pressed against the inner peripheral surface of the brake outer. As a result, the rotation of the brake inner 9 is suppressed and the cam member is returned inward in the axial direction.
Transition to the free state of (d).

Further, in the present invention, the thrust bearing 13 also performs the axial positioning of the axle shaft 1 via the washer 33 and the snap ring 34, so that the axial positioning of the axle shaft 1 is conventionally performed on the rotating shaft side. The sliding that occurs when the inward movement of the axle shaft is restricted by using a snap ring or the like between the fixed spindle and the spindle can be prevented, and the durability can be improved.

FIG. 7 shows the state after shifting to the manual lock state, but since the operation for shifting is the same as that described in the first embodiment, duplicate description will be omitted.

〔The invention's effect〕

As described above, according to the hub clutch of the present invention, the intermediate brake member ensures the braking of the brake inner by the brake outer and, after the completion of the shift to the locked state, the sliding between the both brake members is significantly increased. It can be reduced and durability can be improved.

[Brief description of drawings]

FIGS. 1 (a) and 1 (b) are explanatory views and a partially enlarged view of the entire configuration of the first embodiment of the present invention in the auto mode, and FIGS. 2 (a) and 2 (b) are cam portions and the like in the free state. 2 (c) and (d) are explanatory views of the engaged state of the cam portion and the like when locked, and FIG. 3 is an exploded perspective view of all parts,
4 (a) to (d) to FIGS. 9 (a) and 9 (b) are explanatory views of the second embodiment of the present invention, and FIGS.
(D) is an explanatory view of the entire structure in a free state, an explanatory view of an engagement state of each cam portion, etc., FIGS. 5 (a) to 5 (c) are explanatory views showing a transition process to a locked state, and FIG. (A) and (b) are explanatory views of the configuration at the time of locking, FIG. 7 is an explanatory view showing a manually locked state, FIG. 8 is an exploded perspective view of all components, and FIGS. 9 (a) and (b) are brake inners. FIG. Explanation of symbols 1 …… Axle shaft, 2 …… Drive gear 2a, 25b …… Gear part, 2b, 25a …… Spline part 4 …… Cam member, 4a …… Cam part 5 …… Spindle 8 …… Brake outer, 8a …… Cam section 9 …… Brake inner, 9a, 9b …… Cam section 9e …… Servo cam section (operating piece) 9f …… Engaging projection (operating piece) 11 …… Release plate, 12 …… Circlip 13 ... … Thrust bearing, 14 …… Thrust washer 16 …… Intermediate brake member, 16a …… Taper part 16b …… Claw part, 17 …… Wire brake 17a, 17b …… Engaged end part, 20 …… Bolt 22 …… Spline, 23 …… Opening 24 …… Case, 25 …… Slide gear 26 …… Retainer, 26a …… Retainer arm 26b …… Bend, 26c …… Claw 27 …… Return spring, 28 …… Shift spring 29 ...... Bearing, 30 ...... Knob 31 ...... Boss

Claims (1)

(57) [Claims] 1. A cylindrical case fixed to a wheel hub and having a spline on its inner circumference, a knob rotatably attached to an opening at the front end of the case, and a spline fixed on the outer circumference of the front end of an axle shaft. And a gear portion, a cam member having a spline engagement on the outer periphery of the drive gear so as to be movable in the axial direction and a projecting cam portion on the inner side in the axial direction, and rotation being suppressed by a fixed system. A brake outer having a grooved cam portion that engages with the cam portion of the cam member, an intermediate brake member that engages with a friction surface formed on the brake outer to generate a braking force, and the intermediate brake member. A groove-shaped first cam portion engaging with a protruding cam portion of the cam member and connected to both sides of the groove-shaped first cam portion are provided with an operating piece that presses against a friction surface of the brake outer. And a release plate for releasing the pressure contact of the friction surface between the intermediate brake member and the brake outer, and a brake inner having a second cam portion formed therein, and the brake inner and the brake inner are arranged in constant contact. A thrust bearing and a thrust washer, a slide gear that is slidably supported by a spline on the inner circumference of the case, and a slide gear that is clutch-engaged with a gear portion on the outer circumference of the drive gear when displaced outward in the axial direction, the cam member and the drive gear. A return spring that is stretched between a step portion on the outer circumference and presses the cam member inward in the axial direction, and a cam formed on the knob while slidingly contacting the axially outer surface of the cam member. A retainer having a claw portion engageable with a surface, and a shift spring stretched between the retainer and the slide gear. Hub clutch, characterized in that it becomes more and.