JPH06344792A - Hub clutch unit - Google Patents

Abstract

PURPOSE:To enable selection of the engagement and vice versa between a front-wheel axle and a wheel hub automatically according to their speed differences. CONSTITUTION:A retainer 8 holding a roller 12 is installed in space between an inner ring 2 to lee connected to a front axle 50 and an outer ring 1 to be connected to a wheel hub 52, and this retainer 8 and the inner ring 2 are connected to each other via a clearance in a direction of rotation. A torsional coil spring 17 producing a rotational resistance is attached to one end of the retainer 8, and a rotational resistance imparting means 20 is connected to the other end via a one-way clutch 18. when the front axle is rotated to the wheel hub, the one-way clutch 18 is raced in the case of going forward, whereby the roller 12 is engaged in a state of being on forward standby. In the case of backward in reverse, the one-way clutch 18 is locked, phase of the retainer 18 varies as far as a portion for the rotational direction clearance by the rotational resistance acting on the retainer 18, so that the roller 12 comes to a state of being engaged in the opposite direction against the forward direction. Conversely, rotation of the wheel hub is speedier than that of the front axle, the outer ring overruns on a sprag, so its engagement comes off.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hub clutch device for transmitting and disconnecting a driving force between a front wheel axle and a wheel hub.

[0002]

2. Description of the Related Art In a part-time four-wheel drive vehicle, the rear wheels are always driven, and a hub clutch device is incorporated between the front wheel axle and the wheel hub. There is a system in which a four-wheel drive and a two-wheel drive are switched by transmitting and blocking the driving force to and from the vehicle.

[0003] Conventional hub clutch devices include manual and automatic drive switching methods, but both have only the function of engaging or disengaging the axle and the wheel hub.

That is, in the conventional hub clutch device, the slide gear fitted to the axle is moved by the action of the cam mechanism or the like which is interlocked with the movement of the axle, and the slide gear is meshed with the wheel hub to thereby connect the axle and the wheel hub. Although the connection and disconnection is made, when the hub clutch device is engaged, the axle and wheel hub are directly connected to each other so that the four-wheel drive state is established.Therefore, when turning through tight corners, etc., between the front and rear wheels. Due to the difference in turning distance that occurs, slippage occurs between the front and rear wheels, and it is possible to drive only on unpaved roads or slippery roads.

Therefore, when traveling on a paved road or the like,
Each time the driver needs to switch the engagement of the hub clutch device to disconnect the front and rear wheels from each other, there is a problem that the drive switching operation is troublesome.

In view of the above, the present invention solves the above-described problems, and can automatically switch between engagement and disengagement of the front wheel axle and the wheel hub according to the rotation difference between the front wheel axle and the wheel hub. It is an object of the present invention to provide a hub clutch device that enables driving traveling.

[0007]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, according to the present invention, a drive member connected to a front wheel axle and a driven member connected to a wheel hub are rotatably fitted in and out, and the drive thereof is performed. A retainer is provided between the member and the driven member, and a roller provided for engaging the drive member and the driven member when the retainer and the drive member relatively rotate in the forward and reverse directions is incorporated in a pocket provided in the retainer. The retainer and the drive member are connected so as to rotate together with a gap in the rotational direction, and two rotational force imparting means for imparting rotational forces of different magnitudes in opposite directions to the retainer, and the action of the rotational force. The means for switching the direction with respect to the rotation direction of the drive member is connected.

[0008]

In the above structure, when the vehicle moves forward and the front wheel axle rotates, the rotational force of one rotational force applying means acts on the retainer, and due to the rotational resistance thereof, the retainer corresponds to the clearance in the rotational direction. And the drive member relatively rotate, and the roller moves to the forward engagement operation state. On the other hand, when the vehicle moves backward and the axle rotates in the opposite direction, the operation direction of the rotational force is switched by the operation of the switching means, and the rotational force of the other rotational force applying means acts to cause the retainer and the drive member to oppose each other. Rotate relative to
The roller is engaged in the backward direction.

When the vehicle turns in this state, the wheel hub that rotates integrally with the front wheels rotates faster than the axle, so that the driven member idles against the rollers, and only the rear wheels run.

On the other hand, when the rear wheels slip during running, the rotation of the axle exceeds the speed of the decelerating wheel hub.
The roller engages the driving member and the driven member, the driving force is transmitted to the front wheels, and the four wheels are driven.

[0011]

1 to 9 show a first embodiment of the present invention. FIG. 1 shows a state in which a hub clutch device is attached to a front wheel of a vehicle. A knuckle 51 fixed to a vehicle body except for a tip portion of the front wheel axle 50 is fitted to the knuckle 51, Wheel hub 5 through bearing
2 is rotatably supported. This wheel hub 52
A tire wheel 53, a brake device 54, and the like are attached to the vehicle via bolts.

An inner ring 2 which is a drive member of the hub clutch device A is integrally attached to the front end portion of the front wheel axle 50 by fitting the serration groove 32.
An outer ring 1 serving as a driven member is rotatably fitted to the outer side of the bearing via a bearing 33.

An outer cylinder 3 is rotatably fitted to the outer side of the outer ring 1 via a bearing 35, and an end portion of the outer cylinder 3 is fixed to an end surface of a wheel hub 52 via a ring member 15. ing.

The end surface 1a of the outer ring 1 opposes the inner end surface 3a of the outer cylinder 3 with a gap, and each end surface 1
torque transmission projections 4 and 5 that engage with a and 3a, respectively.
Is provided. As shown in FIG. 3, the torque transmitting protrusions 4 and 5 have rotational play Y (Y = Y ₁ +).
Y ₂ ), and the outer ring 1 and the outer cylinder 3 are formed so as to transmit torque with play Y in the rotational direction without being directly connected.

A cylindrical surface 6 is formed on the inner diameter surface of the outer ring 1, and a plurality of flat cam surfaces 7 are formed at predetermined intervals on the outer diameter surface of the inner ring 2 facing it. Each of the cam surfaces 7 and the cylindrical surface 6 of the outer ring 1 forms a wedge-shaped space in which both sides in the circumferential direction are narrowed.

A bearing 34 is provided between the outer ring 1 and the inner ring 2.
An annular retainer 8 is provided through the
Stopper pin 10 inserted through pin hole 9 in the peripheral wall of inner ring 2
Are connected.

The cage 8 is formed with the same number of pockets 11 as the cam surface 7 in the circumferential direction, and each of the pockets 11 is formed.
Further, the roller 12 and the spring 13 are incorporated. This roller 12 is 1 for each cam surface 7 of the inner ring 2.
They are assembled one by one, and when they are moved by a predetermined amount in the circumferential direction by the cage 8, they are engaged between the cam surface 7 and the cylindrical surface 6, and the outer ring 1 and the inner ring 2 are integrated. Further, the spring 13 is the roller 1
2 and the side wall of the pocket 11, and the roller 12
Is pressed from both sides to hold the cylindrical surface 6 and the cam surface 7 in a neutral position where they do not engage with each other, but when the cage 8 moves a predetermined amount in the circumferential direction, only one spring acts on the roller 12,
Press the roller against the engagement surface.

Further, the spring seat 1 is provided on the end surface of the inner ring 2 on the tip side.
6 is formed, and a torsion coil spring 17 is incorporated between the spring seat 16 and the inner diameter surface of the inner ring 2. The torsion coil spring 17 has one end locked to the spring seat 16 and the other end locked to the retainer 8. The spring force of the torsion coil spring 17 provides a biasing force for rotating the retainer 8 in the opposite direction to the rotation direction. (This torsion coil spring 17 acts as one rotational force applying means).

On the other hand, the rear end portion of the retainer 8 is extended rearward, and its extension arm 14 constitutes a one-way clutch 18. The one-way clutch 18 is connected to the other end via an input ring 19. Rotational resistance imparting means 20 constituting a rotational force imparting means is connected.

As shown in FIG. 6, the one-way clutch 18 has a plurality of inclined cam surfaces 22 formed at regular intervals in the circumferential direction on the inner circumference of a clutch outer ring 21 which is press-fitted into the input ring 19, and the clutch outer ring 21 is formed. An annular retainer 23 is provided between the retainer 8 and the extension arm 14 of the retainer 8, and a small roller 24 as an engaging element and the small roller 24 extend from the inclined cam surface 22 in a pocket provided in the retainer 23. A spring 25 that presses against the surface of the arm 14 is incorporated.

In the above-described one-way clutch 18, when the cage 8 is rotated in the direction of arrow a in FIG. 6 via the inner ring 2, the roller 24 is caught between the cam surface 22 and the extension arm 14 and the cage 8 is formed. The rotation resistance applying means 20 is integrated via the input ring 19. On the contrary, when the cage 8 rotates in the direction of arrow B in FIG. 6, the engagement of the roller 24 is cut off and the cage 8 and the input ring 19 are separated.

Further, the rotation resistance applying means 20 is shown in FIG.
As shown in FIG. 5, the input ring 19 and the resistor case 26 fixed only in the rotational direction in the groove provided in the knuckle 51 are provided, and the flange 19 a provided on the input ring 19 is provided to the resistor case 26 and the torque adjusting member. Resistor 28 between 27,
A spring 31 in which the rubbing portion 29 is rubbed together and the rubbed portion 29 is incorporated between the torque adjusting member 27 and the retaining ring 30.
It is configured to be pressed by.

The spring force of the spring 31 is equal to that of the rubbing portion 2
9 is set to generate a predetermined frictional force, and the frictional force causes a drag torque in the abrading portion 29. The dragging torque causes the cage 18 to move.
A resistance force that delays the rotation is applied to the input ring 19 that is about to rotate together with the input ring 19.

Further, the rotational resistance P ₁ generated at the rubbing portion 29 is set to be larger than the rotational resistance P ₂ applied to the retainer 8 by the spring force of the torsion coil spring 17 described above, and the drive path to the front wheel axle 50. It is set to be smaller than the rotational resistance P _{3 which} acts from P ₂ <P ₁ <P ₃
Are set to have a relationship of. As a result, the one-way clutch 18 meshes with the cage 8 and the input ring 19.
, The rotation resistance of the rubbing portion 29 overcomes the rotation resistance of the torsion coil spring 19 and switches the phase of the cage 8 in the opposite direction.

Further, as shown in FIG. 4, the stopper pin 10 connected to the retainer 8 is loosely fitted in the pin hole 9 in the peripheral wall of the inner ring 2 with a clearance X in the rotational direction. This rotational direction clearance X determines the delay angle of the retainer 8 with respect to the inner ring 2, and its magnitude is determined by the distance from the neutral position of the cam surface 7 and the cylindrical surface 6 of the roller 12 to the engagement position. Is also set large.

The rotation transmission device of this embodiment has the above-mentioned structure, and as shown in FIG. 1, the inner ring 2 is connected to the front wheel axle 50.
The outer ring 1 and the outer cylinder 3 fixed to the wheel hub 52 are connected to each other via the torque transmitting projections 4 and 5 and mounted. In this case, the rotation direction of the inner ring 2 when the vehicle travels forward corresponds to the direction in which the one-way clutch 18 disengages (the arrow B direction in FIG. 6), and the rotation direction during reverse travels in the direction in which the one-way clutch 18 engages. It is set so as to match (the direction of arrow a in FIG. 6).

When the vehicle travels forward in the above-mentioned mounted state, the inner wheel 2 starts to rotate by driving the front wheel axle 50.

The retainer 8 is rotated by the urging force of the torsion coil spring 17, but in this rotating direction, the one-way clutch 18 is in the idling state, so the rotation resistance applying means 2
The 0 input ring 19 is stopped together with the resistor case 26 and the spring 31.

Contrary to the above, when the car moves backward,
When the inner ring 2 starts to rotate, the cage 8 rotates at the same time as the inner ring 2 due to the urging force of the torsion coil spring 17, but the one-way clutch 18 is locked in this rotation direction.
The cage 8 and the input ring 19 rotate integrally. At this time, since the rotation resistance P ₁ of the rubbing portion 29 connected to the input ring 19 is set to be larger than the rotation resistance P ₂ of the torsion coil spring 17, the cage 8 is decelerated by the resistance of the rotation resistance applying means 20. Then, as shown in FIG. 9, the roller 12 is moved in the opposite direction to the standby state in the engaged state between the cylindrical surface 6 and the cam surface 7. After that, the retainer 8 rotates while receiving the rotation resistance of the rubbing section 29, and the roller 12 maintains the standby state.

The retainer 8 for changing the phase of the roller 12 in this way has a one-way clutch 1 when the vehicle is traveling forward.
8 idles, and only the resistance of the torsion coil spring 17 acts,
When retracted, the sliding resistance of the rubbing portion 29 overcomes the torsion coil spring 17 and acts. Therefore, when moving forward,
Even if the inner ring 2 rotates together with the front wheel axle 50, heat is not generated from the bearing, the frictional contact portion 29, and the like, and wear of the frictional friction portion 29 is suppressed.

In the state where the roller 12 is on standby at the engaging position as described above, the outer wheel 1 and the inner wheel 2 rotate at the same speed while the vehicle is moving forward or backward without slipping,
Since the roller 12 is maintained in the standby state, the inner ring 2
Drive force is not transmitted from the outer wheel 1 to the outer wheel 1
It becomes a wheel drive. (In fact, there is a slight slip on the rear wheels during traveling, so there is torque distribution to the front wheels.) When the vehicle turns and has a steering angle, the outer wheels 1 connected to the front wheels
Because the outer ring rotates faster than the inner ring 2, the outer ring 1
Overrun against. For this reason, the front wheels and the rear wheels rotate independently of each other, and the braking phenomenon at the tight corner does not occur.

On the other hand, if the rear wheels slip during forward / backward traveling, the rotation of the inner wheel 2 connected to the front wheel axle 50 exceeds the rotation of the front wheels that slow down as the vehicle speed decreases. And the cam surface 7, and the outer ring 1 and the inner ring 2
Are integrated. This adds driving force to the front wheels,
Switch to 4-wheel drive mode.

In this embodiment, the outer ring 1 is not directly fixed to the wheel hub 52, but the torque transmission projections 4 and 5 are used to transmit the torque with the play Y in the rotational direction. This is the same as providing a play in the rotational direction between the wheel hub 50 and the wheel hub 52, and has the following functions.

When the vehicle is driven forward and stopped on a slope or the like, the rollers 12 are in the standby state in the forward direction.
When the vehicle naturally moves backward due to the inclination of the slope, only the wheel hub 52 rotates in the backward direction with the front wheel axle 50 stopped. At this time, since the roller 12 is rotated in the forward direction in the standby state, there is a problem that a braking phenomenon at a tight corner occurs when the steering wheel is operated in that state.

On the other hand, the outer ring 1 and the wheel hub 52
If there is a play Y in the rotational direction between them (that is, between the axle 50 and the wheel hub 52), even if the wheel hub 52 rotates backward with respect to the stopped axle 50, the wheel hub 52 will be moved by the amount of the play Y. Since the front wheel axle 50 is rotated by the propeller shaft during rotation, the rollers 12 are switched from the standby state in the forward direction to the standby state in the backward direction. Therefore, the outer ring 1 can be overrun with respect to the roller 12, and the occurrence of the above-described tight corner braking phenomenon is prevented.

10 and 11 show a second embodiment.
In this example, two rollers 41 and 42 are arranged between each cam surface 7 and the cylindrical surface 6 in the structure of the first embodiment described above, and both rollers 41 and 42 are separated from each other. A spring 43 that biases in the direction is incorporated.

In the above structure, when the inner ring 2 rotates in the direction of the arrow as shown in FIG. 10, the retainer 44, which decelerates, separates one roller 41 from the engagement position and also causes the spring 4 to move.
The other roller 42 is urged through
Is pressed to the engaging position.

[0038]

As described above, the hub clutch device of the present invention utilizes the engagement and free running of the mechanical clutch, and automatically engages the both in accordance with the rotation difference between the front wheel axle and the wheel hub. Since switching between release and separation is possible, a full-time direct drive type four-wheel drive can be realized without causing a braking phenomenon even when turning a tight corner with the four-wheel direct drive state.

Further, since the engaging element is always kept in the engaging operation state, even if a slight rotation difference occurs between the axle and the wheel hub due to wheel slip or the like, the engaging element can be instantly engaged. There is an advantage that the driving force can be switched with good responsiveness and the strong driving force can be transmitted.

[Brief description of drawings]

FIG. 1 is a partially longitudinal front view showing a first embodiment.

FIG. 2 is an enlarged sectional view of the main part of the above.

FIG. 3 is a sectional view taken along line III-III in FIG.

FIG. 4 is a sectional view taken along line IV-IV in FIG.

FIG. 5 is a view as seen from the line VV in FIG.

FIG. 6 is a sectional view showing a one-way clutch.

7 is a sectional view taken along line VII-VII of FIG.

FIG. 8 is a cross-sectional view showing an operating state of a roller during forward movement.

FIG. 9 is a cross-sectional view showing an operating state of the roller when retracting.

FIG. 10 is a sectional view showing a second embodiment.

FIG. 11 is a sectional view showing the engagement state in the opposite direction of the above.

[Explanation of symbols]

 1 Outer ring 2 Inner ring 3 Outer cylinder 4, 5 Torque transmitting projection 6 Cylindrical surface 7 Cam surface 8 Cage 11 Pocket 12 Roller 13 Spring 17 Torsion coil spring 18 One-way clutch 19 Input ring 20 Rotational resistance applying means

Claims (2)

[Claims] 1. A drive member connected to a front wheel axle and a driven member connected to a wheel hub are rotatably fitted in and out, and a retainer is provided between the drive member and the driven member. A roller that engages the drive member and the driven member when the retainer and the drive member relatively rotate in the forward and reverse directions is incorporated into the provided pocket so that the retainer and the drive member rotate together with a gap in the rotation direction. A hub clutch device that is connected to the retainer, and is connected to two rotational force applying means for applying rotational forces in opposite directions and a means for switching the action direction of the rotational force with respect to the rotational direction of the drive member. 2. The hub clutch device according to claim 1, wherein a rotational direction play larger than a rotational direction clearance between the retainer and the driving member is provided at a connecting portion between the driven member and the wheel hub.