JP3213633B2 - Rotation transmission device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotation transmission device used for switching between transmission and interruption of a driving force on a driving path of a vehicle.

[0002]

2. Description of the Related Art A viscous coupling is conventionally known as a device for transmitting a driving force of an automobile engine to a front wheel and a rear wheel. In such a sharp turn, drag torque is likely to be generated, and the transmission of a large driving force requires a large coupling diameter.

On the other hand, the present applicant has disclosed a device in which a driving force for a front wheel and a rear wheel is switched by a mechanical clutch so that a large driving force can be efficiently transmitted from a low speed. Issue.

As shown in FIG. 12, this device comprises a rotatable first retainer 63 between an outer ring 61 rotatably supported and an inner member 62, and a second retainer fixed to the inner member 62. A container 64 is provided, and a sprag 65 engaged by the relative rotation of the outer ring 61 and the inner member 62 is incorporated in pockets provided in both the retainers 63 and 64.

A pin 67 is inserted into the first retainer 63 through the pin hole 66 of the inner member 62 with a clearance in the rotational direction.
And a rotation resistance applying means 70 using a rolling bearing 71 having a large rotation resistance is connected to the pin 67 via an operating shaft 68 and a pin 69.

Further, a one-way clutch 73 is provided between the rolling bearing 71 and a supporting case 72 connected to a fixed member.
And a torsion spring 74 that applies a rotational force to the first holder 63 in a direction opposite to the rotational direction in which the one-way clutch 73 is disengaged is attached between the operating shaft 68 and the inner member 62. .

The above-mentioned rotation transmitting device is mounted by connecting an inner member 62 to a front wheel propulsion shaft D extending from a transfer C, and connecting an outer wheel 61 to a front teff E in a driving path of an automobile as shown in FIG. However, the one-way clutch 73 idles when the vehicle is moving forward, and the rotation resistance generating means 70
Does not work, and the first retainer 6 is
The rotation of 3 is delayed with respect to the inner member 62 (second retainer 64), and the sprag 65 stands by at the engagement position as shown in FIG.

Conversely, when the vehicle is retracted, the one-way clutch 73 is engaged, and the first retainer 63 and the inner member 62 are relatively rotated by the rotational resistance of the rotational resistance generating means 70, so that the sprag 65 is brought into the engaged position. Make it stand by.

As described above, in the above device, when the vehicle moves forward or backward, the rotation of the first holder 63 is delayed by the resistance of the torsion spring 74 or the rotation resistance applying means 70, and the rotation of the two holders 63, 64 The inclination of the sprag 65 is switched by changing the phase.

[0010]

By the way, in the rotation transmission device having the above structure, when a high torque is applied to the sprag 65, elastic deformation due to contact stress occurs on the contact surface between the sprag 65, the outer ring 61 and the inner member 62. , Sprag 65,
As shown by a dashed line in FIG. 7, it is tilted by the amount of elastic displacement with respect to the standby position.
And the sprags 65 interfere with each other, and a phenomenon occurs in which the load is concentrated and applied to the interfering surface and the fixing pin for fixing the second retainer 64 to the inner member 62. In particular, when a high torque is repeatedly applied to the sprag 65, abnormal wear of the interfering portion or an alternating load is applied to the pillar portion between the pockets of the second retainer 64 and the fixing pin, thereby shortening the life of the component. There is.

Further, in the general usage of automobiles, the forward state occupies most of the time, and the reversal occupies only a very limited time, so that the one-way clutch 73 mainly operates in the idling state. However, since the propeller shaft (front wheel propulsion shaft D) of a normal bicycle is rotating at high speed with several thousand rotations or more, the engagement element of the one-way clutch 73 is rotated in a state of being in contact with the fixed-side clutch surface. Then, there is a problem that wear due to idling remarkably progresses, thereby shortening the life of the clutch and causing inconvenience in meshing.

Also, at the time of retreat, the rotational resistance of the rotational resistance generating means 70 overcomes the rotational resistance of the torsion spring 74,
Since it is necessary to delay the rotation of the first retainer 63, it is required that the drag torque of the rolling bearing 71 is larger than the spring force of the torsion spring 74. However, the rolling bearing 71 is used as the rotation resistance generating means. In the structure, since the drag torque of the rolling bearing 71 obtained by increasing the preload is easily affected by the temperature and it is difficult to obtain a stable torque, there is a disadvantage that it is difficult to control the cage with reliability and high applicability.

In view of the above, the present invention solves the above-mentioned problems, and enables stable transmission of rotational force even when a high-torque load is repeatedly applied to the engaging element, thereby ensuring the reliability of torque switching and increasing the parts height. It is an object of the present invention to provide a rotational force transmission device that can achieve a longer life.

[0014]

According to a first aspect of the present invention, a first retainer and a second retainer having different diameters are provided between an outer ring and an inner member fitted thereto. A retainer is provided, and an engaging element that engages between the outer ring and the inner member by the relative rotation of the two retainers is incorporated into a pocket provided opposite to the two retainers, and the first retainer and the outer ring or the inner ring are engaged. with connecting the member rotating together capable, the rotation resistance applying means for causing rotation difference between the outer ring or the inner side member it and the first retainer is linked provided, the outer ring of the first cage is connected Alternatively, a one-way clutch for disconnecting the connected state of the first retainer and the rotation resistance applying means with respect to the rotation of the inner member in one direction is incorporated, and the second retainer is brought into sliding contact with the outer ring or the inner member in a rotatable manner. And apply an urging force in the direction of crimping to the contact part. The first retainer and the second retainer are rotatably connected via a circumferential gap, and the one-way clutch is disengaged between the first retainer and the second retainer. Rotational force generating means for applying a rotational force in a direction opposite to the operating rotational direction to the first retainer is provided, and the rotational resistance by the rotational force generating means for the first retainer is calculated from the rotational resistance of the rotational resistance applying means The structure was also set to be small.

According to a second means of the present invention, the one-way clutch comprises a clutch outer ring, an inner member, and an engaging element engaged between the two members. It adopted a structure that was built to rotate.

Further, a third means is that the rotation resistance applying means comprises a rubbing portion in which a fixed member and a rotating member are in sliding contact with each other, and an elastic member which presses the rubbing portion. .

[0017]

In the first means, the second retainer is brought into contact with one of the outer ring or the inner member on the driving side, and when a high torque is applied to the engaging element, the second retaining element interferes with the engaging element. A force acts on the retainer. If the acting force exceeds the pressing force of the pressing member, the second retainer slides and reduces the force applied to the retainer and the engaging element. Further, when the second retainer rotates more than the circumferential gap between the first retainer and the first retainer, the first retainer rotates together and keeps the relative positions of the two retainers at a distance required for standby of the engagement element. .

In the second means, the outer ring of the one-way clutch rotates during idling, and the engaging element comes into contact with the outer ring due to centrifugal force to rotate together with the outer ring. The contact pressure between the engaging element and the engaging element is reduced, and the progress of wear during idling is suppressed.

On the other hand, in the third means, a drag torque is generated by pressing the rubbing portion on the member with the elastic member, so that even if the rubbing portion is worn, the pressing force of the elastic member does not change, and Fluctuation in drag torque is prevented.

[0020]

1 to 8 show a first embodiment of the present invention. As shown in FIG. 1, an inner member 2 formed of a hollow shaft is fitted inside an outer ring 1, and both members are formed into a bearing 3 disposed at a rear end of the outer ring 1 and a two-layer structure of the inside and the outside. It is rotatably supported via a pair of built-in bearings 4 and 5. Further, between the open end of the outer race 1 and the peripheral surface of the inner member 2, a rotation resistance applying means 6 described later is rotatably supported via bearings 7 and 8, and the inner member 2 protrudes. At the end,
The input ring 9 is attached by fitting the serration grooves.

As shown in FIGS. 2 and 3, concentric cylindrical engagement surfaces 10 and 11 are formed on the inner diameter surface of the outer race 1 and the outer diameter surface of the inner member 2 opposed thereto. A first retainer 12 and a second retainer 13 having different diameters are incorporated between the engagement surfaces 10 and 11.

The first retainer 12 has an extended arm 14 integrally formed at the rear end thereof, which is inserted between the bearings 4 and 5 having a two-layer structure. Member 2
Are rotatably supported.

On the other hand, the second retainer 13 has a bent portion 15 formed at the front end portion, which is bent toward the inner diameter side, and the bent portion 15 comes into contact with the end surface 2 a of the inner member 2 so as to be able to slide and rotate. A compression spring 16 made of a disc spring is incorporated between the bent portion 15 and the retaining ring 17 of the bearing 3. The crimp spring 16 can bend the bent portion 15 to the end surface 2 a of the inner member 2.
The pressing force generates friction in the contact portion between the two, and the frictional force fixes the second retainer 13 to the inner member 2.

As shown in FIGS. 3 and 7, a plurality of pockets 18 and 19 are formed on the peripheral surface of the first cage 12 and the second cage 13 so as to face each other. A sprag 20 as an engaging element and a spring 21 for holding the sprag are incorporated in 18, 19.

The sprag 20 has an arcuate surface 22 having an outer diameter side and an inner diameter side having a center of curvature on the center line of the sprag.
And the outer ring 1 and the inner member 2 are integrated. Further, the spring 21 has one end supported by the first retainer 12 and presses the sprags 20 from both sides.
The elastic force is held at a position where the elastic member 11 is engaged.

Further, at the front end of the second retainer 13,
As shown in FIGS. 2 and 5, a stopper pin 23 is attached, and the stopper pin 23 is fitted in a square hole 24 provided in the first retainer 12.
Is provided with a rotational gap X.

Further, the first cage 12 and the second cage 1
As shown in FIG. 4, slits 25 and 26 penetrating in the axial direction are formed on the peripheral surface of
A switch spring 2 having a C-shaped ring shape is provided at 5, 26.
7 are engaged with each other. This switch spring 27
It is set in a state of being contracted in the circumferential direction, and is attached by pressing one end to the first holder 12 and the other end to the second holder 13. The power of giving. This force causes the first cage 12
Receives a rotational force in a direction opposite to a rotational direction in which a one-way clutch 28 to be described later engages and rotates to a position where the peripheral wall of the square hole 24 comes into contact with the stopper pin 23 press-fitted into the second retainer 13.

The gap X in the rotational direction between the stopper pin 23 and the square hole 24 is such that the sprags 20 are inclined and engaged with the engaging surfaces 10 and 11 to stand by as shown in FIGS. The two retainers 12 and 13 and the sprag 20 are in a standby state at a meshing position in one direction of rotation by the spring force of the switch spring 27. In the above structure, the switch spring 27 and the two slits 25 and 26 constitute a rotational force generating means.

On the other hand, a one-way clutch 28 for switching the connection between the first cage 12 and the rotation resistance generating means 6 is incorporated at the rear end of the extension arm 14 of the first cage 12. The one-way clutch 28 is, as shown in FIG.
4, a plurality of inclined cam surfaces 30 are formed at regular intervals in the circumferential direction on the inner periphery of the clutch outer ring 29 which is press-fitted into the rear end of the clutch outer ring 29. A roller 33 as an engaging element and a spring 34 for pressing the roller 33 against the inclined cam surface 30 and the surface of the input ring 31 are incorporated in a pocket provided in the retainer 32.

In the one-way clutch 28, when the first retainer 12 rotates in the direction of arrow A in FIG. 6 via the inner member 2, the roller 33 bites between the cam surface 30 and the input ring 31, and The first holder 12 and the input ring 31 are integrated. Conversely, when the first holder 12 rotates in the direction of arrow B in FIG. 6, the engagement of the rollers 33 is broken, and the first holder 12 and the input ring 31 are separated.

As shown in FIG. 1, the rotation resistance generating means 6 includes a flange 35 provided on the input ring 31 and a flange 38 of a housing 37 fixed to a vehicle body or the like via a dust cover 36. The rubbed portions 39 are rubbed with each other, and the flange 38 and the retaining ring 4 are rubbed.
It is configured to be pressed by a disc spring 41 incorporated during the period of zero.

The spring force of the disc spring 41 is set so as to generate a predetermined frictional force in the rubbing portion 39, and this frictional force causes the rubbing portion 39 to generate a drag torque. Thus, a resistance force that delays the rotation of the input ring 31 that is going to rotate integrally with the first retainer 12 is generated.

The rotation resistance generated by the rubbing portion 39 is set to be larger than the rotation resistance applied to the first holder 12 by the above-mentioned spring force of the switch spring 27, and the one-way clutch 28 engages to hold the first holding member. When the device 12 and the input ring 31 rotate together, the rotational resistance of the rubbing unit 39 overcomes the rotational resistance of the switch spring 27,
The phases of the first cage 12 and the second cage 13 are switched in opposite directions.

The rotation transmission device of this embodiment has the above-described structure. To mount the rotation transmission device on a drive path of an automobile as shown in FIG. 9, the input ring 9 of the inner member 2 branches from the transfer C. The front wheel propulsion shaft D is connected, and the outer wheel 1 is connected to the front differential E.

The direction of rotation of the inner member 2 during forward running of the automobile coincides with the direction in which the one-way clutch 28 is disengaged (the direction of the arrow B in FIG. 6), and the direction of rotation during reverse movement is the one-way clutch 28. Are set so as to coincide with the direction of engagement (the direction of arrow A in FIG. 6).

When the vehicle travels forward in the above mounted state, the inner member 2 starts rotating by the drive of the transfer C, and the second retainer 13 integrated with the inner member 2 simultaneously starts rotating. Also, since the first holder 12 is connected to the second holder 13 via the switch spring 27,
Due to the urging force of the switch spring 27, the rotation is delayed with respect to the second retainer 13 by the gap X in the rotation direction between the square hole 24 and the stopper pin 23. For this reason, the sprag 20 is
In the direction shown in FIG.

On the other hand, the outer race 1 of the one-way clutch 28 is rotated by the first cage 12, but in this rotation direction, the one-way clutch 28 is in an idling state. The housing 37 and the disc spring 41 supported by 7 and 8 are in a stopped state. In this case, in the one-way clutch 28, the clutch outer ring 2
When the first cage 12 is rotated at a high speed of several thousand rotations or more by the propeller shaft, the roller 33 is pressed against the outer ring 1 by centrifugal force and rotated, because the first cage 12 rotates by the propeller shaft. For this reason, the contact surface pressure between the roller 33 and the surface of the input ring 31 in the fixed state is reduced, and the friction during idling of the clutch can be suppressed.

On the other hand, when the vehicle moves backward, the inner member 2 and the second retainer 13 start to rotate, and the first retainer 12 is rotated by the biasing force of the switch spring 27. The one-way clutch 28 is locked in this rotation direction, so that the first holder 12 and the input ring 31 rotate integrally. At this time,
Since the rotational resistance of the rubbing portion 39 to which the input ring 31 is connected is set to be larger than the rotational resistance of the switch spring 27, the first retainer 12 is decelerated by the resistance of the rotational resistance generating means 6, and the sprag 20 is moved. As shown in FIG. 8, it is inclined in a direction opposite to the above, and the engagement surfaces 10 and 11 are brought into a standby state in an engagement state. Thereafter, the first holder 12 rotates while receiving the rotational resistance of the rubbing unit 39, and holds the sprag 20 in the standby state.

In this manner, the one-way clutch 28 idles when the vehicle is traveling forward, and only the urging force of the switch spring 27 acts on the first retainer 12 that changes the phase of the sprag 20. The slip resistance of the mating portion 39 works against the switch spring 27. For this reason, even if the inner member 2 rotates together with the propeller shaft during forward movement, no heat is generated from the bearings and the rubbing portion 39, and the wear of the rubbing portion 39 is suppressed.

Further, the rubbing portions 39 which come into sliding contact with each other
Generates a drag torque by being pressed by the disc spring 41 from the outside, so that even if the contact surface is worn, the pressing force of the disc spring 41 does not change, and a rapid torque fluctuation can be suppressed. In addition, the disc spring 41 has a characteristic that the pressing force can be easily set and that the pressing force can accurately follow the amount of change due to wear, so that a drag torque of a planned value can be generated. The torque can be reliably maintained larger than the rotation resistance of the switch spring 27.

In the state where the sprag 20 is on standby at the engagement position as described above, while the vehicle is moving forward or backward without slipping, the outer ring 1 and the inner member 2 are at the same speed (the same speed as the propeller shaft). ), And the sprags 20 are maintained in the standby state.
The driving force is not transmitted to the vehicle, and the vehicle runs only on the rear wheels.

When the vehicle turns and has a steering angle, the outer wheel 1 connected to the front wheel rotates faster than the inner member 2, so that the outer wheel 1 runs over the sprag 20. For this reason, the front wheel and the rear wheel are separated from each other and rotate, and the braking phenomenon at the tight corner does not occur.

On the other hand, when the rear wheel slips during forward and backward running, the rotation of the inner member 2 connected to the transfer C exceeds that of the front wheel, which is decelerated as the vehicle speed decreases, so that the sprag 20 is engaged. The outer ring 1
And the inner member 2 are integrated. As a result, a driving force is applied to the front wheels, and the state is switched to a four-wheel drive state.

If a high torque is applied to the sprags 20 during the transmission of the driving force, the sprags 20 and the engaging surfaces 10 and 11 are elastically deformed. Exerts a large force.

When the acting force exceeds the frictional force generated at the contact portion between the bent portion 15 of the second holder 13 and the inner member 2 by the pressing of the pressure spring 16, the second holder 13 is moved to the inner member 2. , And rotates by the amount of interference with the sprag 20. For this reason, the acting force is reduced, and no excessive force is applied to the second cage 13 and the sprags 20, so that damage to the cages and abnormal wear of the sprags are prevented.

Further, when the second retainer 13 slides and rotates with respect to the inner member 2, the first retainer 12 does not move for a small amount of rotation, but the amount of rotation is smaller than that of the stopper pin 23. When the clearance X in the rotation direction between the square holes 24 becomes larger, the first retainer 12 is driven by the stopper pin 23 and rotates together with the second retainer 13. For this reason, the first cage 12
The positional relationship between the and the second retainer 13 is maintained substantially the same, and the switch function for operating the sprag is not impaired.

FIG. 10 shows a second embodiment. In this example, the center of the torsion coil spring 52 is fixed to the second retainer 13 via the press-fit pin 51, and the free end of the torsion coil spring 52 is attached to the front end of the first retainer 12, Due to the spring force of the coil spring 52, a rotational force is generated in the first holder 12 and the second holder 13 such that the sprag 20 stands by at the biting position when moving forward.

It is preferable that the number of the torsion coil springs 52 be an even number so as to balance the rotation. Since other structures and operations are the same as those of the first embodiment, the same components are denoted by the same reference numerals and description thereof is omitted.

FIG. 11 shows another embodiment of the torque generating means. In this example, the second retainer 13 is brought into axial contact with the inner member by means of an elastic member such as a disc spring, and the stopper pin 23 press-fitted into the second retainer 13 has an arrow F
An axial force is generated as shown in FIG. Further, as shown in FIG. 11, the side of the square hole 24 of the first cage 12 is
The first retainer 12 is formed so as to generate a circumferential component force when the first retainer 12 comes into contact with the stopper pin 23.

In the above structure, when the first cage 12 and the second cage 13 rotate relative to each other, the square hole 24 is formed in the circumferential direction by the action of the axial force F received from the stopper pin 23 and the inclined surface 53. Although the component G is applied, the component G gives a rotational force to the first retainer 12 and becomes a rotational resistance force that causes the sprag 20 to stand by at the engagement position.

In each of the above embodiments, the inner member 2 is used as the input side, and the retainers 12 and 13 are connected to the inner member 2. However, the retainers 12, 13 are connected to the outer ring 1. The same operation as described above can be obtained by connecting the outer ring to the input side.

Although the sprags that engage in the forward and reverse directions have been shown as the engaging elements that engage the outer ring and the inner member, sprags that engage in only one direction of rotation are arranged symmetrically. Can also.

[0053]

As described above, according to the first means of the present invention, the force generated in the retainer due to the interference with the engaging element is reduced by sliding and rotating the retainer. It is possible to suppress abrasion of the pliers and to greatly improve the durability of the device.

In the second means, a one-way clutch for switching the connection between the retainer and the rotation resistance generating means is mounted so that the outer ring rotates, and the contact surface pressure between the engaging element and the fixed clutch surface is reduced. Therefore, wear of the clutch due to idling can be suppressed, and durability of the one-way clutch can be improved.

Further, in the third means, the frictional contact between the fixed member and the rotating member is pressed by the elastic member to generate rotation resistance, so that the torque fluctuation due to wear of the frictional contact portion can be reduced. There is an advantage that stable rotation resistance can be generated.

[Brief description of the drawings]

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

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

FIG. 3 is a sectional view taken along the line III-III of FIG. 1;

FIG. 4 is a sectional view taken along the line IV-IV in FIG. 1;

FIG. 5 is a view taken along line VV in FIG. 2;

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

FIG. 7 is a cross-sectional view showing an operation state of a sprag during forward movement.

FIG. 8 is a sectional view showing an operation state of the sprag when the sprag is retracted.

FIG. 9 is a schematic diagram showing a driving route of an automobile.

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

FIG. 11 is a diagram showing another embodiment of the rotational force generating means.

FIG. 12 is a longitudinal sectional front view showing a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Outer ring 2 Inner member 6 Rotational resistance imparting means 10, 11 Engagement surface 12 First retainer 13 Second retainer 16 Crimping spring 18, 19 Pocket 20 Sprag 23 Stopper pin 24 Square hole 25, 26 Slit 27 Switch spring 28 One-way clutch 31 Input ring 39 Rubbing part 41 Disc spring 52 Torsion coil spring 53 Inclined surface A Rotation transmission device

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-3-14924 (JP, A) JP-A-4-211731 (JP, A) JP-A-60-241532 (JP, A) JP-A-3- 113131 (JP, A) JP-A-5-118358 (JP, A) JP-A-3-334 (JP, U) JP-A-3-11133 (JP, U) (58) Fields investigated (Int. ⁷ , DB name) F16D 41/00-47/06

Claims (3)

(57) [Claims] 1. An outer ring and an inner member fitted to the outer ring,
A first retainer and a second retainer having different diameters are provided, and an engaging element that engages between an outer ring and an inner member by relative rotation of the two retainers is incorporated into a pocket provided opposite to both retainers. ,
The first cage and the outer ring or the inner member are rotatably connected to each other, and the first cage and the outer ring or the inner
A rotation resistance applying means for causing a rotation difference between the first member and the rotation member is provided for the rotation of the outer ring or the inner member in one direction connected to the first cage. In a rotation transmitting device incorporating a one-way clutch for disconnecting a connected state, an elastic member for slidingly contacting the second retainer with an outer ring or an inner member and applying an urging force in a direction of crimping to the contact portion. Is provided, the first cage and the second cage are rotatably connected via a circumferential gap, and the one-way clutch is disengaged and operated between the first cage and the second cage. A rotational force generating means for applying a rotational force in a direction opposite to the rotational direction to the first retainer is provided,
A rotation transmitting device, wherein the rotation resistance of the rotation force generating means is set smaller than the rotation resistance of the rotation resistance applying means with respect to the first retainer. 2. The one-way clutch according to claim 1, wherein the one-way clutch comprises a clutch outer ring, an inner member, and an engagement element engaged between the two members, and is incorporated so that the clutch outer ring rotates when the clutch is idling. times Tenden our apparatus according to claim 1, wherein. 3. The rotating resistance applying means comprises a rubbing portion in which a fixed member and a rotating member slidably contact each other, and an elastic member which presses the rubbing portion. times Tenden our apparatus according to.