JPH0194028A - Freewheel hub device for vehicle - Google Patents

Abstract

PURPOSE:To make 4WD and 2WD selectable as well as to speed up cam operation by operating a clutch mechanism intermittently with a cam mechanism installed in a tip peripheral part of a fixed spindle. CONSTITUTION:A cam mechanism 20 is installed in an axial peripheral part of a fixed spindle 1. This cam mechanism 20 is composed of a cam collar 21 rotatably held on a peripheral part of the fixed spindle 1, a fixed cam face 22 to be formed in an axial outer end of the fixed spindle 1 and slide ring 23 engageable with the cam collar 21 and the cam face 22. The cam mechanism 20 is independent from a power transmission system which transmits rotational driving force of a drive shaft 10 to a wheel hub 3, and it is made into cam operation by utilizing a torque difference between the rotational driving force of the drive shaft 10 and the fixed side of the fixed spindle 1.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a freewheel hub device for a vehicle that allows selection of two-wheel drive and four-wheel drive.

(Prior art) A four-wheel drive vehicle is equipped with a power transmission system that transmits driving force from the engine to each of the front two wheels and the rear two wheels, and is usually driven with two-wheel drive selected, such as when driving on snowy roads or Four-wheel drive is usually selected when necessary for sandy terrain, off-roading, etc.

Selection between two-wheel drive and four-wheel drive is made by the driver operating the transfer. In two-wheel drive, the freewheel is separated from the drive system and rotates freely, and in four-wheel drive, the freewheel is automatically connected to the drive shaft to transmit power.

However, if 2N drive is selected, the driven wheels (driver
The drive system on the side (en wheel) side may spin due to reverse torque, causing noise and mechanical loss, and reducing durability. A freewheel hub device is provided to interrupt transmission and prevent the drive system from idling.

The intermittent torque in this type of freewheel hub device can be manually operated or automatically controlled in accordance with a transfer switching operation.

Manually operated freewheel hub devices have the inconvenience of having to stop the mold each time, get out of the vehicle, and operate from outside the vehicle, and there is also the risk of forgetting to manually operate the device.

On the other hand, automatic freewheel hub devices include a reversible overrunning clutch type in which a roller is housed in a gauge and the clutch wedges together to transmit torque when driving force is applied, and a reversible overrunning clutch type in which a roller is housed in a gauge and the clutch is wedged together to transmit torque when driving force is applied. They are broadly divided into dog clutch types, in which the clutch moves axially and engages with a cam.

(Problems to be Solved by the Invention) The dog clutch type freewheel hub device does not vibrate due to repeated engagement and engagement of the clutch on snowy roads, unlike the reversible overrunning clutch type.
Stable torque transmission can be expected. However, in order for the cam to move the dog clutch in the axial direction, it is necessary to apply a relatively large braking force to the cam, and conversely, the cam constantly drags this braking force, resulting in mechanical loss and cam wear. By! There was a problem in that when the IJ power decreased, the dog clutch became unable to engage, making four-wheel drive impossible.

This invention was made in consideration of the above-mentioned problems, and is a freewheel hub device for a vehicle that improves the dog clutch type and enables the clutch mechanism to reliably engage with the small braking force of the cam mechanism. The main purpose is to provide

[Structure of the invention]

(Means for Solving the Problems) In order to achieve the above-mentioned purpose, the freewheel hub device for a vehicle according to the present invention includes a hollow fixed spindle fixed to the vehicle body side, and a rotatable shaft mounted on the outer periphery of the fixed spindle. a wheel hub supported by a wheel hub; a drive shaft that extends through the fixed spindle and protrudes outward to transmit engine driving force; a power transmission mechanism that transmits rotational driving force of the drive shaft; a clutch mechanism for transmitting rotational driving force from the drive shaft to the wheel hub, and a cam mechanism provided on the outer periphery of the tip of the fixed spindle to connect and disconnect the clutch mechanism, and the cam mechanism is connected to the drive shaft. The system is provided independently from the system for transmitting the rotational driving force of the wheel to the wheel hub, and a clutch mechanism is operated to select between two-wheel drive and four-wheel drive.

(Function) The freewheel hub device of this vehicle is equipped with a cam mechanism on the outer periphery of the tip of a fixed spindle fixed to the vehicle body, and this cam mechanism operates the clutch mechanism intermittently to transfer the rotational driving force of the drive shaft to the wheel. The on/off of the clutch mechanism that transmits data to the hub is controlled, and the vehicle is selected between four-wheel drive and two-wheel drive by controlling the on/off of the clutch mechanism.

Moreover, the cam mechanism that operates the clutch mechanism intermittently is installed on the outer periphery of the tip of the fixed spindle, independent of the system that transmits the rotational driving force of the drive shaft to the wheel hub, and is connected to the fixed side and the rotational driving force of the drive shaft. Since the cam operation is performed based on the difference, the cam operation is rapid and the braking force acting on the cam mechanism can be reduced.

(Example) Hereinafter, an example of the present invention will be described with reference to the accompanying drawings.

FIG. 1 is a tuft side view showing a preferred embodiment of the freewheel hub device for a vehicle according to the present invention, in which the upper half of the freewheel hub device is a four-wheel drive vehicle with the clutch ON, and the lower half of the freewheel hub device is a four-wheel drive vehicle with the clutch ON. shows the two-wheel drive state with the clutch OFF.

In FIG. 1, reference numeral 1 indicates a fixed spindle 1 fixed to a vehicle body 2 of a four-wheeled vehicle, and a wheel hub 3 is rotatably supported on the outer circumference of this fixed spindle 1 via a bearing 4.4. A cylindrical main body casing 5 of the freewheel hub device is fixed to the outer end of the wheel hub 3 in the axial direction at its 7 flange portions 5a with fixing tools such as bolts 6. A male thread 7 is formed on the outer periphery of the main body casing 5 in the axial direction, and a female thread 9 of the cap 8 is attached to the male thread 7.
are screwed together, and the main casing 5 is opened from the outside.

On the other hand, a drive shaft 10 is inserted into the fixed spindle 1 and is rotationally driven from an engine (not shown) via a drive power transmission system such as a transfer.

The tip of the drive shaft 10 passes through the fixed spindle 1 and protrudes outward in the axial direction, and a spline 11 is attached to this protruding tip.
is engraved. The internal teeth 128 of the cylindrical drive gear 12 mesh with this spline 11, and the drive gear 1
A retaining ring 13 restricts the axially outward sliding of the Nidrive gear 12, which is rotatably supported and slidably slidable in the axial direction.

External teeth 12b are carved on the outer peripheral surface of the drive gear 12, and these external teeth 12b are internal teeth or splines 1 carved on the inner peripheral surface of the sleeve-shaped drive clutch 14.
It is always engaged with 5. In this case, the drive gear 12 is a power transmission WtE! that transmits the driving force of the drive shaft 10 to the drive clutch 14! It makes up the structure. This drive clutch 14 is held slidably in the axial direction, and clutch external teeth 16 are formed on the outer peripheral surface of the drive clutch 14 on the outside in the axial direction. The clutch outer teeth 16 are formed by clutch inner teeth 17 carved on the inner circumferential surface of the main body casing 5 on the outside in the axial direction.
It is held so that it can be engaged with. In this case, the main casing 5
constitutes a driven clutch, and a clutch mechanism 18 is formed from the drive clutch 14 and the driven clutch 5.
It can be configured to be connected freely.

Further, a cam mechanism 20 is provided on the axial outer circumference of the fixed spindle 1. The cam mechanism 20 includes a cam collar 21 rotatably held on the outer circumference of the fixed spindle 1;
Fixed spindle 1. As shown in FIG. 3, it is formed of a fixed cam face 22 formed on the outer end surface in the angular direction, and a slide ring 23 that can be engaged with the cam collar 21 and the cam face 22. cam! 1 fX20 is independent from the power transmission system (the drive gear 12 of the power transmission mechanism, the clutch mechanism 18, and the main body casing 5) that transmits the rotational driving force from the drive @ 10 to the wheel hub 3, and the rotational drive of the drive shaft 10 The cam is actuated by utilizing the rotational force difference between the rotational force and the fixed side of the fixed spindle 1.

On the other hand, the cam collar 21 of the cam mechanism 18 is attached to the presser finger 26 of the spring washer 25 held by the fixing mechanism 24.
It is supported elastically and immovably in the axial direction through a sliding ring 27 such as a web washer so as to be lightly braked in the rotational direction. The thrust force of the cam collar 21 is received by a ring plate-shaped rotating bearing 28.
As a result, the cam collar 21 is held rotatably while receiving a braking force from the spring washer 25 and the like. Further, the fixed m structure 24 has a double nut structure, and this double nut 30.31 is screwed to a female thread carved on the outer surface of the fixed spindle 1, and the lock washer 32 and the key groove 33 are screwed together.
Rotation is stopped by.

The keyway 33 extends in the axial direction on the outer surface of the fixed spindle 1.

On the other hand, the slide ring 23 of the cam mechanism 20 is accommodated in a collar sleeve 35 so as to be slidable in the axial direction, and the return sling 3 normally accommodated in the collar sleeve 35
6, it is pressed against the cam collar 21 of the cam mechanism 20 and the cam face 22 of the fixed spindle 1. Inward movement of the slide ring 23 in the axial direction is restricted by a stop ring 37.

Further, the collar sleeve 35 is rotatably housed within the main body casing 5. At this time, a ring plate-shaped rotating bearing 38 is provided between the axially outer end of the collar sleeve 35 and the driven clutch portion of the main body casing 5 so that the collar sleeve 35 rotates smoothly within the cylindrical surface within the main body casing 5. is interposed, and force/ra sleeve 3
Three dents are formed on the outer surface of 5, and these dents 39
lubricating oil is retained in the As shown in FIG. 2, the rotary bearing 38 has a large number of small balls 38b (bearings) disposed within a ring plate 38a at appropriate intervals in the circumferential direction.

Further, on the slide ring 23 of the cam mechanism 20, bar-shaped engagers 40, 40 that can come into contact with the cam face 22 and the cam collar 21 of the fixed spindle 1 are diametrically opposed and protrude radially inward. This engager 40 is inserted into a guide groove 41 extending axially in the cylindrical portion 14a of the drive clutch 14, and is held in an engaged state by a retaining ring 42. At this time, a suppression spring 44 is interposed between the slide ring 23 and the clutch external teeth 16 of the drive clutch 14, and the spring 44 allows the drive clutch 14 and the slide ring 23 to elastically move relative to each other in the axial direction. Supported.

The relative sliding amount of the drive clutch 14 and the slide ring 23 is regulated by the length of the guide 8I41 and the stop ring 42.

On the other hand, the cam collar 21 of the cam mechanism 20 and the cam face 22 of the fixed spindle 1 are formed as shown in FIGS. 3 to 5. Among these, the cam face 22 has a V-shape or a U-shape, and consists of a bottom surface 22a, an inclined surface 22b rising obliquely from the bottom surface 22a, and a top surface 22c. For example, a pair is formed facing each other in the direction.

The cam collar 21 is used in combination with the cam face 22, and includes a pair of diametrically opposed engagement projections 46, shoulder portions 47 formed on both sides of the engagement projections 46, and a bottom surface forming a concave portion. 48. This bottom surface 48 is lower than the bottom surface 22a of the cam face 22 when the cam collar 21 is combined with the cam face 22 of the fixed spindle 1. The shoulder portion 47 includes a tapered surface 47a and a holding surface 47 following this tapered surface 47a.
The holding surface 47b is slightly higher than the top surface 22c of the cam face 22, and the tapered surface 47a intersects with the top surface 22C of the cam face 22 midway. By intersecting the tapered surface 47a with the top surface 22C of the cam face 22, the engager 40 of the slide ring 23 is moved from the cam face 22 to the cam collar 2.
This makes it easy to transition to 1.

Next, the operation of the freewheel hub device will be explained.

During two-wheel drive, since the drive shaft 10 does not rotate, the bar-shaped engager 40 of the slide ring 23 of the cam mechanism 20 is pressed against the bottom surface of the V-shaped or O-shaped groove of the cam face 22 of the fixed spindle 1 by the return spring 36. 22a
and is located axially inwardly. Therefore, the drive clutch 14 is biased inward in the axial direction by the spring force of the return spring 36, so that the drive clutch 14 and the driven clutch 5 do not engage with each other, and the clutch mechanism 18 is kept in the clutch OFF state. Therefore, the wheel hub 3 can rotate freely (see the lower half of FIG. 1 and FIG. 4).

When you operate the transfer and set it to four-wheel drive, the drive shaft 10
rotates, and this rotation causes the drive clutch 14 and slide ring 23 to rotate via the drive gear 12.

As the slide ring 23 rotates, the engager 4
0 moves along the V-shaped or U-shaped inclined surface (cam) 22b of the cam face 22 of the fixed spindle 1, and pushes the slide ring 23 outward in the axial direction against the spring force of the return spring 36. , slide.

At this time, the engaging element 40 of the slide ring 23 moves up from the bottom surface 22a of the cam face 22 of the fixed spindle 1 over the inclined surface 22b to the top surface 22C, and touches the shoulder of the cam collar 21 that intersects with this top surface 22c. Part 4
The slide ring moves onto the tapered surface 47a of No. 7, then slides on the tapered surface 47a, collides with the engagement protrusion 46, is held by the holding surface 47b, presses the engagement protrusion 46 and rotates, and the slide ring 23 is maintained in a state displaced outward in the axial direction. In this case, the shoulder portion 4 of the cam collar 21
The tapered surface 47a formed at 7 intersects the top surface 22C of the spindle cam face 22, the lower part of the taper is lower than the top surface, and the upper part of the taper (retaining surface 47 bllII)
is smoothly inclined to be higher than the top surface 22c, so the engaging element 40 of the slide ring 23 smoothly transitions from the top surface 22C of the cam face 22 to the tapered portion 47a of the cam collar 21.

Further, a holding surface 47b formed on the shoulder portion 47 of the cam collar 21 is formed continuously with the tapered surface 47a, and is higher than the top surface 22c of the spindle cam face 22. Therefore, when the slide ring 23 is held by the holding surface 47b of the cam collar 21 and rotates, rs friction between the slide ring 23 and the top surface 22c of the fixed spindle cam face 22 is prevented, and wear of the spindle cam face 22 is prevented. Effectively and reliably prevented.

On the other hand, as the slide ring 23 moves outward in the axial direction, the drive clutch 14 is also elastically pressed and moved outward in the axial direction via the pressing spring 44, and the external teeth 16 of the clutch The clutch 11K117 of the casing) 5 engages with the clutch mechanism 18, and the drive shaft 10
The rotational driving force of the wheel is transmitted to the wheel hub 3.

At this time, the slide ring 23 tries to move inward in the axial direction due to the reaction force of the suppression subring 44, but this movement is prevented by the fixing 1124 that holds the cam collar 21, while the thrust force acting on the cam collar 21 is Absorbed by a plate-like rotation bearing 28, the cam collar 21 rotates freely around the fixed spindle 1. At this time, an oil groove 49 is formed on the outer surface of the fixed spindle 1 so that this rotation can be performed smoothly.

Also, the slide ring 23 is attached to the holding surface 4 of the cam collar 21.
The action held on 7b is Kaku! This is continued as long as the e-axis 10 rotates (including when it rotates due to reverse torque from the wheel side due to meandering operation, etc.).

When returning the vehicle from four-wheel drive to two-wheel drive, operate the transfer to set it to two-wheel drive, disconnect the power transmission system that transmits power from the engine to the drive shaft 10, and then
After freeing the vehicle, move the vehicle slightly in the opposite direction.

As a result, rotation is applied to the drive shaft 10 from the ground side via the wheel clutch mechanism 18, the drive shaft 10 rotates in the opposite direction, and the slide ring 23 also rotates in the reverse direction.

By reverse rotation of the slide ring 23, the bar-shaped engager 40
is guided from the holding surface 47b of the cam collar 21 to the tapered surface 47a to the bottom surface 48 side, and this cam collar 21
The slide ring 23 moves onto the cam face 22 of the fixed spindle 1 at the position where it has slid onto the bottom surface 48 of the slide ring 23, and falls into the bottom surface 2a of the cam face 22 by the spring action of the return spring 36.

As the engager 40 of the slide ring 23 is guided by the bottom surface 22a of the cam face 22, the slide ring 23' moves inward in the axial direction, and the drive clutch 1
4 is pulled back inward. As a result, in the clutch mechanisms 18 of the drive clutch 14 and the driven clutch 5, the outer clutch m16 and the inner clutch teeth 17 are disengaged, and the wheel hub 3 becomes free to rotate. At that time, Mukara 21
Since the holding surface 47b has a short length in the circumferential direction, a slight reverse rotation of the slide ring 23 ensures that the clutch n structure 1
Release the mesh of 8 and change from the meshed ON state to the non-meshed O
It can be put into the FF state, and four-wheel drive is eliminated.

In this way, the freewheel hub device of this vehicle controls the engagement and disengagement of the clutch mechanism 18 by the cam t [20 provided on the fixed spindle, and the cam collar 21 controls the engagement state of the clutch IMIi1s and the engaged state fil (ON state).
t added to Kammler 21.
The ill power is unrelated to the engagement force of the clutch mechanism 18, and can be achieved by creating a slight rotational difference between the cam collar 21 and the slide ring 23 when the clutch mechanism 18 is disengaged. Since the braking force is sufficient, it can be set extremely small compared to the braking force that contributes to the clutch engagement operation of the conventional clutch mechanism, resulting in less mechanical loss and improved durability.

In addition, since the cam face 22 is provided on the hollow fixed spindle 1 fixed to the vehicle body side, the clutch mechanism 18 can be quickly connected and connected due to the difference in rotation between the fixed side and the drive shaft. Furthermore, if a detection switch such as an indicator light is installed on the bottom surface 22a of the cam face 22 in order to determine the operating position of two-wheel drive and four-wheel drive, for example, the cam face 22 is fixedly placed. , it becomes easier to set up and wire electrical circuits.

FIG. 6 shows another embodiment of the freewheel hub device for a vehicle according to the present invention.

The freewheel hub device shown in this embodiment is used when the upper half of the center line is in two-wheel drive (clutch OF:
F), its lower half is in 4-wheel drive (clutch ON)
Indicates the status of This freewheel hub device is basically different from the freewheel hub device shown in Figs. 1 and 2 in the structure of the cam mechanism and the holding structure of the cam collar that constitutes this cam 1@, and the other parts are different. Since this is only a difference in design and is substantially the same, the same reference numerals will be given and the explanation will be omitted.

The cam mechanism 50 of this freewheel hub device is composed of a cam collar 51, a cam face 52 formed on the outer end surface of the fixed spindle 1, and a slide ring 53. The cam face 52 includes a bottom surface 52a that is perpendicular to the axis, an inclined surface 52b that expands outward from both sides of the bottom surface 52a, and a surface that is perpendicular to the axis and continues from the inclined surface 52b. A pair of top surfaces 52c are provided facing each other in the diametrical direction.

The cam collar 51 is fixed in the axial direction on the outer layer of the outer end of the fixed spindle 1, is lightly braked in the rotational direction, and is pivotally supported on the rotating part by the holding device 55. That is, fixed spindle 1
There is a male thread 57 and a keyway 58 on the outside surface of the
0 are engaged and overlapped, and further the fastening ring 61 is removed, and the above three members are connected by a fastening screw 62. At this time, the inner end flange 51a of the cam collar 51 is clamped between the detent washer 60 and the fastening ring 61 with a friction plate 63 and a wave washer 64 placed on the front and back sides thereof. As a result, the cam collar 51 can rotate under light < tlJ motion, and its center in the axial direction is restricted to a constant position.

Further, on the outer end surface of the cam collar 51, as shown in FIG. 7, a bottom surface 65 of the recessed stepped portion, a holding surface 66, and an engaging protrusion 67 protruding outward at the center thereof are arranged. When the cam collar 51 is pivotally supported by the spindle 1 as described above, the bottom surface 65 of the recessed stepped portion is located at the same level or slightly inward from the inner end of the inclined surface 52b of the cam face 52, and the holding surface 66 is Although it coincides with the top surface 5a of the cam face 52,
It is set to be located slightly outward.

Further, the slide ring 53 is rotatably held on the inner peripheral surface of the rotatable collar sleeve 35 by a sliding key 68 so as to be slidable in the axial direction. This sliding key 66 is interposed between the inner peripheral surface of the slide blade ring 53 and the outer peripheral surface of the drive clutch 14. A circlip 69 is fitted to the inner end of the drive clutch 14, and the circlip 69 restricts relative inward movement of the slide ring 5j. That is, with the above configuration, the drive clutch 14 and the slide ring 53 are each rotatably mounted to the drive wheel 10 so as to be slidable in the axial direction, and are coupled so that the distance between them can be relatively reduced. . The above-mentioned combined body is the rotating collar sleeve 35 and the slide ring 5.
The return spring 36 is biased inwardly by the return spring 36 installed between the A circlip 70 is fitted onto the rotating collar sleeve 35 to restrict its inward movement.

An engaging element 72 that extends axially inward and bends in the axial direction is provided at the inner end of the slide ring 53, and the engaging element inner end 72a faces the cam face 5 of the spindle 1. .

The system is constructed as described above, and its functions are as follows.

In the case of two-wheel drive, since the drive shaft 10 does not rotate, the engager F572a of the slide ring 53 is rotated between the cam face V and the U-shaped inclined surface 5 by the action of the return spring 36.
2b, the combined body of the slide ring 53 and the drive clutch 14 is located inward, and the clutch southern part 1
6.17 is not engaged. Therefore, the wheel hub 3 can rotate freely (see the upper half of Figure 6 and Figure 8).
.

When you operate the transfer and set it to four-wheel drive, the drive shaft 10
rotates, and at the same time the slide ring 53 and drive clutch 14 rotate. With this rotation, the engager inner end 72a
moves along the cam face V-shaped inclined surface 52b, and the slide ring 25 moves against the force of the return spring 36.
push outward. At this time, the engager inner end 72a moves from the inclined surface 52b to the top surface 52c, and
The holding surface 66 of the cam collar 51 is set to almost match the
get on.

At this time, since the cam collar 51 is being braked in the rotational direction, the inner end 72a of the engager slides on the holding surface 66, collides with the engagement protrusion 67, and continues to push the engagement protrusion 67 and rotate. , the slide ring 53 is held in a state of being moved axially outward.

As the slide ring 53 moves outward in the axial direction, the drive clutch 14 also moves outward via the suppression spring 44, and the clutch teeth 16 and 17 mesh to connect with the driven clutch 15, causing the wheel hub 3 to rotate. convey. When the clutch teeth 16 and 17 collide with each other, due to the subrig force of the pressing spring 44! Fi! I will be treated. The effect of holding the slide ring 53 on the rotating spacer holding surface 66 continues as long as the drive shaft 10 rotates (including when it rotates by receiving reverse torque from the wheel side due to meandering operation, etc.).

When returning from four-wheel drive to two-wheel drive, the transmission system of the drive shaft 10 is disconnected by operating the transfer, and the wheels are slightly moved in the opposite direction by two-wheel drive. As a result, rotation is applied from the ground side, the drive shaft 10 rotates in the opposite direction, and the slide ring 53 also rotates in the opposite direction. The inner end 72a of the engager is attached to the holding surface 6
Move 6 in the opposite direction and make the cam face 53 with a concave position.
Then, due to the spring action of the return spring 36, the cam face 52 falls from the inclined surface 52b into the bottom surface 2a,
The drive clutch 14 is pulled back inward, the lower parts 16 and 17 of the clutch are disengaged, and the wheel hub 3 is free to rotate. Since the circumferential length of the V-shaped inclined surface 5b and the recessed step portion of the holding surface 66 is set to be sufficiently short, the engagement of the clutch 5.14 can be reliably disengaged by a slight reverse rotation.

FIG. 10 shows a modification of the power transmission mechanism of the freewheel hub device.

In the freewheel hub device shown in FIGS. 1 and 2, a drive gear with splines carved on the inner and outer circumferential surfaces serves as a power transmission mechanism for transmitting power from the drive shaft 10 to the drive clutch 14 of the clutch mechanism 18. We have shown an example using the 10th drive gear instead of this drive gear.
A rotation preventing collar sleeve 75 may be used as shown in the figure.

When using the anti-rotation collar sleeve 75, instead of carving a sleeve line at the tip of the drive shaft 10, a key groove (not shown) extending in the axial direction is provided, and the stop key 76 is inserted into this key groove. The rotation may be prevented by fixing the rotation prevention collar sleeve 75 by holding the rotation prevention collar sleeve 75 and mounting a drive clutch (not shown) to the rotation prevention collar sleeve 75 via a stop key 77. In this case, the anti-rotation collar sleeve 7
It is necessary to form key grooves for the stop keys 77 and 78 on the inner and outer circumferential surfaces of 5 and on the inner circumferential surface of the drive clutch.
There is no need to carve teeth or splines on the inner surface of the anti-rotation collar sleeve or drive clutch.

Further, a thrust washer 78 is fixed to the inner end of the anti-rotation collar sleeve 75, and the side surface of the thrust washer 78 is closely opposed to the outer end of the retaining protrusion 67 of the cam collar 51.

As shown in FIG. 10, the anti-rotation collar 75 of this freewheel hub device has a thrust washer 78 at the inner end.
are integrally combined or formed, and when the locking collar 75 is fixed to the drive shaft 10 by the locking key 76, the inner surface of the thrust straw shirt 8 is in close proximity to the outer end surface of the engaging protrusion 46 or 67 of the cam collar 21 or 51. are set to face each other. On the other hand, the drive shaft 10 is aligned with the inner end of the fixed spindle 1 by a bushing 79 (see FIGS. 1 and 6), and is connected to the inner end surface of the spindle 1 through a flange 79a provided near the inner end of the bushing 79. The stepped portion 80 of the drive shaft 10 receives a thrust force outward in the axial direction of the drive tank 1o.

Further, the thrust washer 78 receives an axially inward thrust force of the drive f*10 by the engaging protrusion 67.

Since there is no relative rotational difference between the thrust washer 78 and the engagement protrusion 67 during rotation of the drive shaft 10, there is no wear and it is suitable for preventing the drive shaft 1o from being pulled out.

This freewheel hub device for a vehicle has the configuration and function as described above, and can prevent the drive shaft from being pulled out with a clean structure using component parts. Conventionally, a circlip was inserted between the spindle end face, but
The product of this invention has no relative rotation difference and is highly durable.
In addition, the cam face can be freely formed on the end face of the spindle, which has the effect of improving the functionality of the freewheel hub device.

(Effects of the Invention) As described above, the freewheel hub device for a vehicle according to the present invention includes a cam structure provided on the outer periphery of the tip of the fixed spindle, and the cam structure controls engagement and engagement of the clutch mechanism. Moreover, the meshing action of the clutch mechanism is maintained, and since the cam mechanism is independent from the system that transmits the rotational driving force of the drive shaft to the wheel hub, the cam mechanism can be operated independently of the meshing action force of the clutch mechanism. The braking force applied to the cam mechanism is extremely small compared to the braking force that contributes to the meshing operation of the clutch mechanism like a conventional cam ring.

In addition, since the cam mechanism can be provided using a fixed spindle fixed to the vehicle body, the cam operation of the cam mechanism can be obtained by the rotation difference with the drive shaft, and the intermittent operation is quick. The small υ1 power of the mechanism allows the clutch mechanism to reliably engage and perform clutch action.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view showing one embodiment of a freewheel hub device for a vehicle according to the present invention, FIG. 2 is an exploded perspective view of the freewheel hub device with the wheel hub removed, and FIG. 3 is an exploded perspective view of the freewheel hub device described above. FIG. 4 is an exploded perspective view showing the cam mechanism incorporated in the freewheel hub device, FIG. 4 is an exploded view showing the principle of the two-wheel drive state of the freewheel hub device, and FIG. 5 is the four-wheel drive state of the freewheel hub device. FIG. 6 is a developed view without showing the state in principle; FIG. 6 is a vertical sectional view showing another embodiment of the freewheel hub device for a vehicle according to the present invention; FIG.
The figure is an exploded perspective view showing the cam mechanism of the freewheel hub device shown in FIG. 6, FIG. 8 is a diagram showing the principle of the two-wheel drive state of the freewheel hub device shown in FIG. 6, and FIG. FIG. 6 is a diagram showing the principle of the four-wheel drive state of the freewheel hub device d, and FIG. 10 is a longitudinal sectional view showing a modification of the power transmission mechanism of the freewheel hub device of the present invention. DESCRIPTION OF SYMBOLS 1... Fixed spindle, 2... Vehicle body, 3... Wheel hub, 5... Main body casing, 8... Cap, 10... Drive shaft, 11... Spline, 12...
・Drive gear (power transmission ti4M), 14...
Drive clutch, 15... Spline (internal teeth), 1
6...Clutch external teeth, 17...Clutch internal teeth, 18
...Clutch mechanism, 20...Cam mechanism, 21...
Cam collar, 22...cam face, 22a...bottom surface, h2b...slanted surface, 22C...top surface,
23...Slide ring, 24...Fixing mechanism, 25
...Spring washer, 27...Sliding ring, 2
8.38...Rotating bearing, 30.31...Nut, 32...Lock washer, 35...Color sleeve, 36...Return spring, 37...Retaining ring, 40...Bar shaped engagement element, 44...pressing spring, 46...engaging protrusion, 47...shoulder part,
47a... Tapered surface, 47b... Holding surface, 50...
・Cam Il! Structure, 51... Cam collar, 52... Cam face, 52a... Bottom surface, 52b... Inclined surface, 52G... Top surface, 55... Holding device, 57
...Male thread, 58...Key full, 59...Nut,
62... Tightening male screw, 63... Friction plate, 64... Wave washer, 65... Bottom surface, 66... Holding surface, 67... Engagement protrusion, 68... Sliding key , 72・
... Engagement element, 75 ... Rotating collar sleeve, 76
．． 77...Stop key, 78...Thrust washer,
79...Butshu.

Claims (1)

[Scope of Claims] 1. A hollow fixed spindle fixed to the vehicle body, a wheel hub rotatably supported on the outer periphery of the fixed spindle, and a wheel hub inserted through the fixed spindle and protruding outward to drive the engine. A drive shaft to which force is transmitted, a power transmission mechanism that transmits the rotational driving force of the drive shaft, a clutch mechanism that transmits the rotational driving force from the power transmission mechanism to the wheel hub, and a clutch mechanism that connects and disconnects the clutch mechanism. The fixed spindle has a cam mechanism provided on the outer periphery of the tip of the fixed spindle, and the cam mechanism is provided independently from a system for transmitting the rotational driving force of the drive shaft to the wheel hub, and the cam mechanism is provided with a clutch mechanism. A freewheel hub device for a vehicle, characterized in that two-wheel drive and four-wheel drive can be selected by operating. 2. The power transmission mechanism consists of a drive gear with teeth carved on the inner and outer peripheral surfaces of a hollow cylindrical body, and this drive gear is rotatably provided on a spline carved on the tip of the drive shaft, and The outer teeth of the gear are engaged with the drive clutch of the clutch mechanism.
Freewheel hub device as described in section. 3. The power transmission mechanism consists of a rotation prevention collar fixed to the tip of the drive shaft via a stop key, and this rotation prevention collar is rotationally integrally engaged with the drive clutch of the clutch mechanism via a stop key. A freewheel hub device according to claim 1. 4. The freewheel hub device according to claim 3, wherein a thrust washer is fixed inward in the axial direction of the rotation prevention collar. 5. The clutch mechanism includes a drive clutch that is rotationally integrated with the drive gear of the power transmission mechanism and is supported slidably in the axial direction, and a driven clutch that meshes with the clutch teeth of the drive clutch, and the driven clutch has a cylindrical shape. A freewheel hub device according to claim 1, wherein the freewheel hub device is fixed to a wheel hub in a shape. 6. The drive clutch is a cylindrical main body casing that is fixed to the wheel hub, and internal clutch teeth are formed on the inner peripheral surface of the tip of the drive clutch, and these internal clutch teeth can mesh with the external clutch teeth of the drive clutch. A freewheel hub device according to claim 5. 7. The cam mechanism includes a cam collar that is axially integral with the outer circumference of the tip of the fixed spindle and is rotatably held with a braking force in the circumferential direction, a cam face formed on the tip surface of the fixed spindle, and the cam collar. The freewheel hub device according to claim 1, comprising: and a slide ring which is provided with an engager that can be engaged with a cam face and is held slidably in the axial direction. 8. The engager of the slide ring is always spring-biased toward the fixed spindle, selectively engages with the cam collar and the cam face of the fixed spindle, and is held in the axial direction. Freewheel hub device. 9. The cam face of the fixed spindle has a bottom surface, a top surface, and an inclined surface extending from the bottom surface to the top surface, while the cam collar has an engaging protrusion, a shoulder section substantially perpendicular to the axis, and a recessed step section. 2. The freewheel hub device according to claim 1, wherein the bottom surface of the cam collar is lower than the bottom surface of the cam face, and the shoulder portion thereof is higher than the top surface of the cam face. 10. The shoulder part of the cam collar has a holding surface for the engaging element adjacent to the engaging protrusion, and a tapered surface that slopes upward toward this holding surface.The holding surface is slightly higher than the top surface of the cam face, and has a tapered surface. 10. The freewheel hub device according to claim 9, wherein the cam face intersects with the top surface of the cam face midway.