JPH0771491A - Reverse rotation preventive bearing device - Google Patents

Abstract

PURPOSE:To provide a reverse rotation preventive bearing device by which an output side rotary shaft can be prevented from rotating reversely by force from the side to which rotation is transmitted and rotation transmitting efficiency in normal operation can be maintained high. CONSTITUTION:In a bearing device 10 used in a worm speed reduction device 4 having a motor output shaft 3 on which a worm 5 is installed to mesh with a worm wheel 6 connected to the output side, the device has a one-way clutch function to regulate rotation of the motor output shaft 3 by a combinational condition of a thrust load on the bearing device 10 side to be applied to the motor output shaft 3 and the rotational direction of the motor output shaft 3, and this one-way clutch function regulates the rotation of the motor output shaft 3 by bringing a taper part 11 formed on the motor output shaft 3 and clutch balls 12 formed in a bearing device into contact with each other.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reverse rotation preventing bearing device, and particularly to a structure in which the rotation shaft on the rotation transmission side (output side) is reversed by the force from the rotation transmission side. To provide a reverse rotation preventing device capable of preventing rotation and maintaining high rotation transmission efficiency during normal operation, and for example, to a bearing device for preventing reverse rotation of a rotary shaft suitable for a speed reducer for window lifting of an automobile and the like. Is.

[0002]

2. Description of the Related Art For example, in a worm device that decelerates and transmits a rotation of a motor through a worm and a worm wheel, a motor rotating shaft (output shaft) by an external force from a side to which the rotation is transmitted (that is, a worm wheel) Reverse rotation was prevented by increasing bearing loss and motor idling torque due to worm deceleration.

However, if the bearing loss and the motor idling torque are reduced in order to reduce the output torque of the motor and increase the output of the motor, the motor rotating shaft reverses due to the external force from the output shaft. For example, taking a power window motor as an example, the window glass is pushed down, or due to vibrations during running,
The inconvenience of opening easily is expected.

Therefore, a technique of providing a spiral spring-like reverse stopper on the shaft on the worm wheel side, and a resin having a relatively large coefficient of friction as a thrust bearing of the motor rotating shaft are used to apply an external force from the worm wheel side. When the thrust load is applied to the motor rotating shaft, the technology to prevent the reverse rotation due to the friction of the thrust bearing can be considered.

[0005]

However, the above-described reverse rotation stopper technique requires a large force to be applied to the shaft after control in a low speed range, that is, the shaft after deceleration. However, the technology using the friction of the thrust bearing has a disadvantage that the friction of the thrust bearing is generated even during normal operation, resulting in a reduction in rotation transmission efficiency.

An object of the present invention is to prevent the rotation shaft on the output side from being reversed by the force from the side to which the rotation is transmitted, and to keep the rotation transmission efficiency during the normal operation high with a simple structure. It is an object of the present invention to provide a reverse rotation preventing bearing device.

[0007]

A reverse rotation preventing bearing device according to a first aspect of the present invention includes a worm wheel connected to an output side and an output shaft to which a worm that meshes with the worm wheel is attached. In a bearing device used for a worm speed reducer, the bearing device has a one-way clutch function of restricting rotation of the output shaft depending on a combination condition of a thrust load applied to the output shaft on the bearing device side and a rotation direction of the output shaft. The one-way clutch function is characterized in that the taper portion formed on the motor output shaft and the bearing portion formed on the bearing device come into contact with each other to regulate the rotation of the motor output shaft.

A reverse rotation preventing bearing device according to a second aspect of the present invention is a bearing used for a worm speed reducer, comprising a worm wheel connected to an output side, and an output shaft having a worm engaged with the worm wheel attached thereto. In the device, the bearing device has a one-way clutch function of restricting the rotation of the output shaft according to a combination condition of a thrust load applied to the output shaft to the bearing device side and a rotation direction of the output shaft,
The one-way clutch function is output by a groove formed on the output shaft, a sphere that abuts on the groove and rotates, and a regulating member that has tapered portions on both inner wall surfaces and that regulates the movement of the sphere by the tapered portion. It is characterized in that the rotation of the shaft is restricted.

[0009]

The operation of the reverse rotation preventing bearing device according to the first aspect will be described. For example, when the motor is driven to open the window glass, the motor output shaft and the worm wheel meshing with the motor output shaft are rotated, and the motor output shaft is a worm. When a thrust load is generated by the wheel, the reverse rotation prevention bearing device is installed at the end of the motor output shaft, so the thrust load is not received and the taper part and the bearing part are separated from each other, and the one-way clutch function does not work. Since the motor output shaft is not regulated, the motor output shaft can be freely rotated in both forward and reverse rotation directions, so that the rotation is efficiently transmitted.

Next, for example, when the motor is driven to close the window glass, the motor output shaft rotates, and the worm wheel meshing with this rotates. The motor output shaft produces a thrust load due to the load that rotates the worm wheel. At this time, the taper portion and the bearing portion come into contact with each other, but since they function as a one-way clutch that regulates the reverse rotation of the rotation direction of the motor output shaft, in this case, the rotation of the motor output shaft is not regulated, that is, it rotates efficiently. Is transmitted.

On the other hand, for example, when the window glass is opened without driving the motor, when the worm wheel is rotated by the force to open the window glass, the motor output shaft produces a thrust load and meshes with each other. Therefore, a rotational force is generated. At this time, the reverse rotation preventing bearing device receives this thrust load, that is, the taper portion and the bearing portion come into contact with each other, and in this case, the motor output shaft generates a rotational force in the rotation restricting direction, so that the reverse rotation preventing movement is prevented. The one-way clutch function of the bearing device restricts its rotation, and the motor output shaft does not rotate.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. The members, arrangements, and the like described below do not limit the present invention and can be variously modified within the scope of the gist of the present invention.

1 to 5 show an embodiment according to claim 1, FIG. 1 is a schematic view in which a reverse rotation preventing bearing device is used in a worm speed reducer, and FIG. 2 is an enlarged cross-sectional view of a main part of FIG. 3, FIG. 3 is a sectional view taken along the line AA of FIG. 2, FIG. 4 is an enlarged sectional view of an essential part similar to FIG. 2 showing a state where no load is applied to the bearing side, and FIG. 5 is a sectional view taken along the line BB of FIG. is there. In this example, in FIG.
The description will be made assuming that the window glass is configured to open in the case of rotation in the direction of arrow O.

In FIG. 1, reference numeral 10 is a reverse rotation preventing bearing device, and a motor (not shown) is provided with a motor output shaft 3 (only one of which is shown in FIG. 1) extending on both sides, and a tip portion of the motor output shaft 3 is provided. The bearing device 10 is arranged on the side.

On the motor output shaft 3 between the bearing device 10 and the motor, a worm 5 forming a part of the reduction gear device 4 is attached integrally with the motor output shaft 3. The worm wheel 6 that constitutes a part of the speed reducer 4 is meshed. In this worm wheel 6,
The output shaft 6a is attached. An output pinion that meshes with a fan-shaped gear portion (not shown) is attached to the output shaft 6a. A taper portion 11 is formed on the tip end side of the motor output shaft 3 of this example.

The bearing device 10 has a taper portion 11, a clutch ball 12 as a bearing portion, a tip end receiving portion 13, a clutch ball holding portion 14, and a clutch housing 15 as main constituent elements.

The taper portion 11 of the present example has a cylindrical shape, and the outer periphery of the motor output shaft 3 on the tip end side is tapered with a predetermined taper, and a concave portion 11a is formed at the tip end. Has been done.

The clutch ball 12 as a bearing portion is held by a clutch ball holding portion 14 so that it can rotate and move between a rolling surface 15a and a stopper surface 15b of a clutch housing 15 which will be described later. There is.

The tip receiving portion 13 is provided with a ball 13b which engages with the concave portion 11a of the tapered portion 11, and the ball 13b is provided between the concave portion 11a of the tapered portion 11 and the bottom surface 15c of the clutch housing 15. Held in. The motor output shaft 3 has a clearance L between itself and the tip receiving portion 13, and is configured to move in the thrust direction by, for example, about 0.1 to 0.3 mm.

The clutch housing 15 of this embodiment is box-shaped, has a hole 15d for inserting the taper portion 11 formed in the center thereof, and has a rolling surface 15a on the inner periphery thereof as shown in FIG.
And the stopper surface 15b is provided at a plurality of positions (in the example shown in the figure, 4
Are formed). Then, the tapered portion 11 which is the tip of the motor output shaft 3 having the tip tapered is provided with the hole 15
It has a structure inserted from d.

The clutch ball holding portion 14 of the present embodiment is composed of a frame body which allows the clutch ball 12 to move in the direction of the rolling surface 15a and regulates the movement in other directions. Then, the clutch ball 12 moves in the circumferential direction together with the clutch ball holding portion 14, and the stopper 12a and the stopper surface 1 are moved.
The movement in the circumferential direction is restricted by 5b.

Next, the operation of the bearing device 10 having the above structure will be described with reference to the embodiment shown in FIGS. First, the case of driving the motor to open the window glass will be described. When the motor is driven by a power source (not shown) to open the window glass, the motor output shaft 3 rotates in the direction of arrow O in FIGS. The worm 5 integrated with the output shaft 3 rotates, and the worm wheel 6 meshing with the worm 5 rotates in the arrow X direction. The rotation of the worm wheel 6 is transmitted to the main arm via a fan-shaped gear portion (not shown), the glass holder descends, and the window glass opens.

At this time, the motor output shaft 3 is moved rightward in FIG. 1 (arrow N in FIG. 1) by the load for rotating the worm wheel 6 in the direction of arrow X (that is, the load for opening the window glass).
Direction thrust force is generated. At this time, since the reverse rotation preventing bearing device 10 is installed at the left end of the motor output shaft 3, it does not receive a thrust load, and the ball 13b and the tip receiving portion 13 have a clearance of about 0.1 to 0.3 mm. Therefore, the positional relationship between the clutch ball 12 and the taper portion 11 is as shown in FIGS. 4 and 5. In this state, the reverse rotation preventive bearing device 10 does not limit the motor output shaft 3 and can freely rotate in both forward and reverse rotation directions, so that the rotation is efficiently transmitted.

Next, when the motor is driven to close the window glass, the motor output shaft 3 is rotated in the direction of arrow P by driving the motor in FIGS. 1 and 3, and the worm wheel 6 meshing with the motor output shaft 3 is indicated by arrow Y. Rotate in the direction. The rotation of the worm wheel 6 is transmitted to the main arm via the fan-shaped gear portion, the glass holder descends, and the window closes. At this time, the motor output shaft 3 is rotated in the left direction (see FIG. 1) by the load that rotates the worm wheel 6 in the arrow Y direction.
Thrust load is generated in the direction of arrow M).

The reverse rotation preventing bearing device 10 receives a thrust load, and the clearance between the ball 13b and the tip end receiving portion 13 is clogged. Therefore, the positional relationship between the clutch ball 12 and the taper portion 11 is as shown in FIG. In this state, the reverse rotation preventing bearing device 10 functions as a one-way clutch that restricts rotation of the motor output shaft 3 in the direction of arrow O. In this case, however, the motor output shaft 3 rotates in the direction of arrow P, and therefore rotation is restricted. That is, the rotation is efficiently transmitted. When the window glass rises and reaches the upper limit (or the lower limit), the limit switch is opened (closed) to stop the rotation of the motor.

When the motor output shaft 3 is moved to the right in FIG. 1 (in other words, as shown in FIG. 4,
(When there is a clearance L of about 0.1 to 0.3 mm between the left end receiving portion and the motor output shaft 3), the taper portion 11 and the clutch ball 12 are in contact with the stopper 12a, and the clutch ball 12 and the rolling surface are in contact with each other. The clearance of 15a is maintained. At this time, both the forward and reverse rotation directions can be freely rotated (see FIGS. 4 and 5).

On the other hand, in the power window, when a force for rotating the motor output shaft 3 is applied from the worm wheel 6 side without driving the motor as in the case of opening the window by hand, that is, the worm wheel 6 side. To warm 5
When rotating (that is, the motor output shaft 3), the worm wheel 6 rotates in the direction of the arrow X, but at this time, the direction of the thrust load is opposite to that described above, so that the motor output shaft 3 and the bearing device 10 are rotated. To the clutch ball 12 side of the arrow M
A thrust load is applied in the direction, and the motor output shaft 3 is pressed against the clutch ball 12 of the bearing device 10.

This force causes the motor output shaft 3 to generate a thrust load in the left end direction of FIG. 1 (direction of arrow M in FIG. 1), and due to the meshing, a rotational force in the direction of arrow O is generated. At this time, the reverse rotation preventing bearing device 10 receives the thrust load,
That is, the positional relationship between the clutch ball 12 and the taper portion 11 is in the same state as that shown in FIG. 3, and in this case,
Since the motor output shaft 3 generates a rotational force in the direction of arrow O, its rotation is restricted by the one-way clutch function of the reverse rotation preventing bearing device 10, and the motor output shaft 3 does not rotate.

In short, the thrust load of the motor output shaft 3 is applied to the clutch ball 12 side of the bearing device 10, and the taper portion 11 of the motor output shaft 3 and the clutch ball 12 are brought into pressure contact with each other by the thrust load. Friction occurs between the output shaft 3 and the clutch ball 12 of the bearing device 10, and the motor output shaft 3 does not rotate together with the worm speed reduction ratio.

As described above, in the rotation transmission from the worm wheel 6 side to the worm 5 side, the taper portion 11 causes the clutch ball 1 to move.
It moves to the rolling surface 15a side while slidingly contacting with 2, and the peripheral surface of the clutch ball 12 is sandwiched between the rolling surface 15a and the taper portion 11, and the motor output shaft is locked. Therefore, the motor output shaft 3 becomes unrotatable due to the friction between the motor output shaft 3 and the clutch ball 12 together with the worm speed reduction ratio, and the motor output shaft 3 is prevented from reversing due to the external force applied to the worm wheel 6.

FIGS. 6 to 11 show other embodiments. In these drawings, the same reference numerals are given to the same arrangements and the same members as those in the above-mentioned embodiments, and the description thereof will be omitted.

FIG. 6 is an enlarged sectional view of the essential parts showing another embodiment. In this example, the clutch ball 12 and the tip receiving portion 13
This is an example in which coil springs 23 and 24 are provided for the ball 13b.

In this example, a ring-shaped clutch receiver 21 and
A ring-shaped spring receiver 22 is disposed in contact with the clutch receiver 21, and coil springs 23 and 24 are disposed between the spring receiver 22 and the bottom surface 15c of the clutch housing 15. A support plate 25 is arranged between the coil spring 24 for the tip receiving portion 13 and the ball 13b.

The coil spring 24 of this example is 0.1 to
It has a movable range of about 0.3 mm, and is configured so that there is no gap between the tip of the motor output shaft 3 and the tip receiving portion 13 when the motor output shaft 3 moves. With the configuration as in this example, the clutch ball 1 is formed by the coil spring 23.
2 is pressed in the direction of coming into contact with the taper portion 11 side, the same operational effect as that of the above-described embodiment is obtained, the rotation can be regulated more reliably, and the clutch ball 12 can be prevented from running out of play. The occurrence can be reliably prevented.

In this example, at least three clutch balls 12 are used. In addition, although an example using a coil spring is shown in this example, if a movable range of about 0.1 to 0.3 mm is provided, a leaf spring as described below or a synthetic resin having a good restoring force is used. You may comprise. Further, a ball 13b is provided on the tip end, for example, the tapered portion 1
The tip of 1 may be processed into a spherical shape, and the tip of the motor output shaft 3 itself may receive it. That is, the shape is not limited as long as the shape can receive the thrust load and can rotate efficiently.

FIG. 7 is a cross-sectional view of an essential part showing another embodiment. In the embodiment shown in FIG. 6, the coil spring 24 is used.
Instead of the coil spring 23, a ring-shaped leaf spring 34 having a V-shaped cross section is used, and instead of the coil spring 23, a leaf spring 33 having a protruding cross section is used.

That is, the rolling surface 15a and the stopper surface 15b of the clutch housing 15 are formed by forming a step 31 on the outer wall side of the other parts, and at the step 31, the clutch receiver 21 and the ring-shaped spring receiver are formed. 22 and 22 are arranged via the leaf spring 33. Even if it is configured as in this example, it is possible to obtain the same effects as those of the embodiment shown in FIG.

FIG. 8 is a cross-sectional view of a main part of another embodiment, showing an embodiment in which a taper roller 41 is used instead of the clutch ball 12 shown in the above embodiment. In this example, the inner wall surface 15e of the clutch housing 15 is tilted, and the taper roller 41 fitted to the tilted inner wall surface 15e and adapted to the taper portion 11 is used.

Reference numeral 42 is a rotation holding shaft of the taper roller 41. By configuring as in this example, it is possible to obtain the same operational effect as in the above-described example, and to control a larger rotational force.

FIG. 9 shows another embodiment of the present invention. In this example, the motor output shaft 3 is extended from both sides of the motor, and the bearing devices 10, 1 are provided at both ends of the motor output shaft 3.
0'is arranged. At this time, in FIG. 10, a one-way clutch function that constitutes the bearing device 10 on the left side,
The one-way clutch function which constitutes the bearing device 10 'on the right side is configured so that the direction of rotation restriction is opposite.

In the structure of this embodiment, the operation of the bearing device 10 on the left side of FIG. 9 is the same as that of the embodiment of FIG. 1, so the description thereof will be omitted and the operation of the bearing device 10 'on the right side will be described. When the motor output shaft 3 rotates in the direction of the arrow O and the thrust load is applied in the direction of the arrow N as in the above-described embodiment, the motor output shaft 3 receives the thrust load on the bearing device 10 'on the right side in FIG. The motor output shaft 3 comes into contact with and closely contacts the bearing device 10 'on the right side. At this time, the bearing device 1 on the right side
Since 0 is restricted in rotation in the direction of arrow P and not restricted in direction O, even if the motor output shaft 3 receives a thrust load and is pressed against the bearing device 10 'on the right side, there is no effect.

Further, when the motor output shaft 3 rotates in the direction of arrow P and a thrust load is applied in the direction of arrow M as in the case of the above embodiment, the motor output shaft 3 becomes the bearing device 10 'on the right side in FIG. A thrust load is applied to the opposite side, and the motor output shaft 3 slightly contacts with or separates from the right bearing device 10 '. Therefore, the bearing device 10 'on the right side is
The motor output shaft 3 rotates without interference with the one-way clutch function.

On the other hand, when an external force for rotating the worm wheel 6 in the Y direction is applied from the worm wheel 6 side without driving the motor, that is, the worm 5 (that is, the motor output shaft 3) is moved from the worm wheel 6 side to the P side. When rotating in the direction, the direction of the thrust load is opposite to that described above, so that the motor output shaft 3 moves toward the clutch ball 1 of the bearing device 10 '.
A thrust load in the direction of arrow N is applied to the 2 side, and the motor output shaft 3 is pressed against the clutch ball 12 of the bearing device 10 '.

In short, when the thrust load of the motor output shaft 3 is applied to the clutch ball 12 side of the bearing device 10 'and the motor output shaft 3 rotates in the P direction, the taper portion 11 of the motor output shaft 3 and the clutch The ball 12 and the ball 12 are pressed against each other by the thrust load, and the motor output shaft 3
Friction occurs between the clutch ball 12 of the bearing device 10 ′ and the worm speed reduction ratio, and the motor output shaft 3 does not rotate. The present embodiment can be suitably applied to, for example, a positioning mechanism in a power seat motor, that is, a motion stop in both rotation directions.

FIG. 10 is a cross-sectional view of the essential parts showing a further embodiment. In the reverse rotation preventive bearing device 10 in this example, a spring (a leaf spring in this example) having a specific spring constant is provided in the thrust receiver, and the thrust load of the motor output shaft 3 causes the thrust displacement of the motor output shaft 3. Instead of using the clutch balls 12 and the like for restricting the rotation as in the above-mentioned respective embodiments while having a structure in which the amount changes, instead of these, the taper portion 11 of the motor output shaft 3 is used.
The metal bearing 50 is provided with a tapered portion 51 so as to receive the metal bearing 50, and the tapered portions 11 and 51 contact each other to suppress the rotation of the motor output shaft 3.

Here, the taper portion 51 is shown in FIG.
A description will be given based on the operation diagram shown by. Generally, the taper is
T: Reverse rotation prevention braking force (Kgf / cm), μ: Tapered portion friction coefficient, F: Thrust load (Kgf) exerted on the tapered portion by the shaft, Effective R: Tapered portion radius (cm) effective for braking force, θ: Assuming the taper angle (deg) with respect to the thrust direction,

[0047]

[Formula 1]

It becomes For example, in the case of a power window motor, the required T is 2 (Kgf / cm), and μ (in this example, the friction coefficient between sintered metal and steel) ≈ (near equal) 0.13, F ≈ ( Near equal) 30 Kgf,
If the effective radius R ≒ (near equal) 0.25 cm,

[0049]

[Formula 2]

Therefore, θ≈ (near equal) is 29 degrees. That is, the tapered portion of the bearing is 29 with respect to the axial direction.
The degree is suitable.

Next, a reverse rotation preventing bearing device 1 having the above-mentioned structure
The operation of 0 will be described. In the power window motor,
During normal operation such as driving the windshield, the motor output shaft 3 is not subjected to such a large thrust load (for example, about 10 kgf). At this time, the motor output shaft 3
The leaf spring 34 disposed at the tip of the motor keeps the motor output shaft 3 at a position where the taper portion 11 of the motor output shaft 3 and the taper portion 3 of the bearing metal 50 do not come into contact with each other, thus efficiently transmitting rotation.

Next, for example, when the window glass is completely closed, a large thrust load corresponding to the motor output is applied to the motor output shaft 3 (for example, about 40 kgf). At this time, the motor output shaft 3 pushes down the leaf spring 34 arranged at the tip of the motor output shaft 3, and the taper portion 11 abuts the taper portion 51 of the bearing metal 50 to rotate the motor output shaft 3. Suppress. And, the motor is energized by this leaf spring 3
It is cut off when 4 is pushed down.

If the window is pushed down by hand in this state, a thrust load in the same direction is applied and the taper portion 11,
Since 51 is in contact, reverse rotation of the motor output shaft 3 is prevented. By changing the spring constant of the leaf spring 34, it is possible to cope with motors having different outputs. Then, in the motor output shaft 3 and the tapered portions 11 and 51 of the bearing metal 50, the rotation suppression force (braking force) of the motor output shaft 3 can be adjusted by the surface friction coefficient and the taper angle thereof.

In the above embodiment, an example of a window lifting device using a motor has been described, but a window lifting device for opening and closing the window by operating a manual handle,
It is also suitably used for a motor that rotates forward and backward such as a power seat motor.

As described above, according to the present embodiment, since the reverse rotation prevention bearing device 10 is only arranged at the end of the motor output shaft 3, a compact and simple structure can be obtained, and a normal operation can be achieved. Since the one-way clutch function does not interfere with the rotation of the motor output shaft 3 during operation, the reverse rotation of the motor output shaft 3 can be prevented without reducing the rotation transmission efficiency during normal operation.

12 to 30 specifically show claim 3, FIG. 12 is a schematic view in which a reverse rotation preventing bearing device is used in a worm speed reducer, and FIG. 13 is an enlarged cross-sectional view of a main part of FIG. 14 is a view for explaining the shape of the hold chip, FIG. 15 is a perspective view of the hold chip, FIG. 16 is a plan view of the hold chip, FIG. 17 is a sectional view taken along the line CC of FIG. 16, and FIG.
19 is a sectional view taken along line D-D of FIG.
20 is a sectional view taken along the line FF of FIG. 16, FIGS. 21 and 22 are plan views showing a state where no load is applied, and FIGS. 23 and 24.
25 is a plan view showing a state in which a load is applied, FIG. 25 is an explanatory view of the action corresponding to the GG cross section of FIG. 21, and FIG. 26 is H of FIG.
-H is an explanatory view of the action corresponding to the section, FIG. 27 is I- of FIG.
An operation explanatory view corresponding to the I section, FIG. 28 is JJ of FIG.
29 is an explanatory view showing an operation corresponding to a cross section, FIG. 29 is an explanatory view showing a state where a load is applied, and FIG. 30 is an explanatory view showing a state where no load is applied. In this embodiment, the same members and the like as those in the previous embodiment are designated by the same reference numerals and the description thereof will be omitted.

A bearing metal 61, which receives the radial load of the motor output shaft 3, is disposed on the end side of the motor output shaft 3. The reverse rotation prevention bearing device 10 is disposed on the end side of the bearing metal 61. The reverse rotation preventing bearing device 10 in this example includes a hold tip 62 as a restricting member, a clutch ball 63 as a sphere, a groove 64 formed in the motor output shaft 3, a tip receiving portion 13, and the like. There is.

The hold chip 62 of this example is formed as shown in FIGS. 14 to 20. That is, by forming the surfaces indicated by symbols a ', b', c ', d', e ', and f'in FIG. 14 into curved surfaces, curved surfaces as shown in FIG. 15, that is, clutch surfaces b, c, d. , E, f are provided with the concave groove 62a. As shown in FIG. 13, the a surface is
It is formed as an arc surface along the outer peripheral surface of the motor output shaft 3.

The clutch surfaces b, c, d, e, f are formed as tapered surfaces so as to be substantially parallel to the respective side surfaces 64a, 64b of the groove 64 formed in the motor output shaft 3 described later. Has been done. Also, this clutch surface b,
d is seen from the thrust side with each surface,
As the motor output shaft 3 moves in the circumferential direction, the distance from the groove 64 becomes closer. Furthermore, surface c and surface be
And the surface df, the clutch ball 63 is in the thrust direction (see FIG.
2 and 13 are formed at intervals so that they can be displaced by a predetermined distance in the left-right direction.

The clutch surface will be further described. As shown in FIGS. 14 to 20, the clutch surface is b.
It has a continuous surface of −e, a c surface, and a continuous surface of df, and the continuous surface of be and the continuous surface of df are formed to face each other. In the continuous surface of b-e and the continuous surface of d-f, the b surface and the d surface are formed as the same inclined surface, and the e surface and the f surface are formed as the same inclined surface. d-
The continuous surface of f is formed in a twisted state. The hold tip 62 is fixed to a portion such as a housing that does not rotate together with the motor output shaft 3.

Groove 64 formed in motor output shaft 3 of this example
Are formed as V-shaped grooves 64 (64a, 64b). Further, the clutch ball 63 as a ball in this example includes the hold tip 62 and the groove 6 formed on the output shaft.
4, and is arranged so as to be able to roll.

The motor output shaft 3 of this example has a tip receiving portion 13
It has a clearance between it and and can be displaced in the thrust direction by a predetermined distance. Even when the motor output shaft 3 is fully displaced to the left and right ends, a clearance remains between the V-shaped groove 64 and the clutch ball 63 and the clutch surface that are displaced along with the displacement. It has become the amount.

The operation of the bearing device 10 having the above structure will be described with reference to FIGS. 12 and 21 to 30. First, when the motor is driven to open the window glass, the motor output shaft 3 rotates in the direction of arrow O in FIG. 12, the worm 5 integrated with the motor output shaft 3 rotates, and the worm wheel meshing with the worm 5 rotates. 6 rotates in the direction of arrow X.

At this time, a load for rotating the worm wheel 6 in the direction of arrow X (that is, a load for opening the window glass) is applied to the motor output shaft 3, so that a thrust load is generated in the right direction in FIG. For this reason, the motor output shaft 3 moves to the full right, and at this time, the positional relationship between the clutch ball 63 and the hold tip 62 of the reverse rotation preventing bearing device 10 is as shown in FIG. 30 in the thrust direction.

At this time, since the motor rotating shaft 3 is rotating in the direction of arrow O, the clutch ball 63 is moved to the side where the distance between the clutch surface and the V-shaped groove 64 is long when viewed from the right clutch surface side. 21 and 25. Therefore, a clearance remains between the clutch ball 63 and the clutch surface, which does not prevent the motor output shaft 3 from rotating in the direction of the arrow O, and efficient rotation can be obtained.

Next, when the motor is driven to close the window glass, the motor output shaft 3 rotates in the direction of arrow P in FIG. 12, and the worm 5 integrated with the motor output shaft 3 is formed.
Rotates, and the worm wheel 6 meshing with the worm 5 rotates in the arrow Y direction. At this time, since a load for rotating the worm wheel 6 in the arrow Y direction is applied to the motor output shaft 3, a thrust load is generated in the left direction in FIG.

Therefore, the motor output shaft 3 moves to the left to the full extent, and at this time, the positional relationship between the clutch ball 63 and the hold tip 62 of the reverse rotation preventing bearing device 10 becomes as shown in FIG. 29 in the thrust direction. At this time, since the motor rotating shaft 3 is rotating in the direction of arrow P, the clutch ball is seen from the left clutch surface and the clutch surface and the V-shaped groove 6
4 is moved to the side away from the distance (that is, the state of FIGS. 22 and 26). Therefore, a clearance remains between the clutch ball 63 and the clutch surface, which does not prevent the motor output shaft 3 from rotating in the arrow P direction, and efficient rotation can be obtained as before.

On the other hand, when the window glass is opened without driving the motor, the force for opening the window glass (not shown) attempts to rotate the worm wheel 6 in the direction of arrow X in FIG. This force causes the motor output shaft 3 to generate a thrust load in the leftward direction in FIG. 12, but since the worm and the worm wheel mesh with each other, a rotational force in the direction of arrow O is generated.

For this reason, the motor output shaft 3 moves to the full left direction, and at this time, the positional relationship between the clutch ball 63 and the hold tip 62 of the reverse rotation preventing bearing device 10 is as shown in FIG. 29 in the thrust direction. At this time, the clutch ball 63 is shaped so as to be sandwiched between the right side surface 64b of the V-shaped groove 64 and the clutch surface b (see FIGS. 24 and 28), and the motor rotation shaft tries to rotate in the arrow O direction.

However, when the motor output shaft 3 is about to rotate in the direction of the arrow O, the clutch ball 63 moves to the clutch surface and V.
It is moved to the side closer to the groove 64 (that is, the state of FIGS. 23 and 27). Therefore, the clutch ball 63
Tries to get caught between the clutch surfaces, and the motor output shaft 3
Is pushed downward in FIG. This force causes friction between the motor output shaft 3 and the bearing metal 61, and prevents the motor output shaft 3 from rotating in the arrow O direction.

According to this example, the reverse mechanism when the window glass is closed without driving the motor is also prevented by the same mechanism as above (FIGS. 24 and 28). The configuration of this example can also be applied to a motion stop in both rotation directions such as positioning with a power seat motor.

Further, in this example, the motor output shaft 3 is provided with the V-shaped groove 64, but the groove shape is the clutch ball 6
3 is displaced in the thrust direction like the motor output shaft 3,
In addition, it may be substantially parallel to the clutch surface attached to the hold tip 62, and may be, for example, the R surface, and is not limited to the shape of the above embodiment.

FIG. 31 shows another embodiment, in which a tip receiving leaf spring is provided and the tip of the motor output shaft 3 is processed into a spherical shape. The leaf spring of this example has a movable range of a predetermined distance. With the configuration as in this example, the tip receiver of the reverse rotation preventing bearing device 10 can be configured so that no clearance is generated between the tip of the motor output shaft 3 and the tip receiver when the motor output shaft 3 moves. It goes without saying that a coil spring may be used instead of the leaf spring.

As described above, the tip of the motor output shaft 3 is processed into a shape capable of receiving a thrust load such as a sphere and rotating efficiently as in this example without disposing a sphere in the tip receiving portion. However, it may be received by the motor output shaft itself.

32 to 35 show another embodiment, FIG. 32 is an explanatory view, FIG. 33 is a partial cross-sectional explanatory view of a hold chip for explaining the operation, and FIG. 34 is KK of FIG.
FIG. 35 is an operation explanatory view seen from the line, and FIG. 35 is an operation explanatory view seen from the line LL in FIG. 34. In this example, the same members and the like as those in the above-described example are designated by the same reference numerals and the description thereof will be omitted. In this example, the shape of the hold tip 62 is changed so that the clutch ball 63 is locked by the V-groove 64 provided on the motor output shaft 3 and the hold tip 62 by the force of the axial component of the motor output shaft 3. It is what The clutch ball 63 in this example is made of a ferromagnetic material.

That is, as shown in FIG. 33, the top surface (bottom surface) of the hold chip 62 is a mountain-shaped inclined surface 81a,
81b. Similarly, the groove 64 of the motor output shaft 3
Is a flat surface portion 82c and inclined surfaces 82a and 82b extending upward on both sides of the flat surface portion 82c. And slope 8
1a and 82a have the same inclination angle θ1, and the inclined surface 81b
And the inclined surface 82b have the same inclination angle θ2. Further, the distance between the inclined surface 81 and the inclined surface 82 is formed so as to contract (become smaller) on one end side as shown in FIG. The lines connecting the equal distances are L1, L2, L3 and r1, r2 in FIG.
As indicated by r3, the configuration is such that it shrinks toward the diagonals 83 and 84.

Magnets 91, 92, 93, 94 are embedded in the inner wall surface of the hold tip 62. Then, stoppers 95 are provided at the tip receiving portions on the end side of the motor output shaft 3 (in this example, stoppers are provided at both ends as shown in FIG. 32).

Next, the operation of the above-described structure will be described. The operation of the above-described embodiment is performed by, for example, FIGS.
35, when the motor output shaft 3 moves to the right, the clutch ball 63 moves together with the groove 64, and when the motor output shaft 3 rotates counterclockwise as indicated by the arrow P in FIG. 63 is moved to the side where the distance between the inclined surface 81a and the inclined surface 82a is close. Therefore, the clutch ball 6
3 is sandwiched between the groove 64 (the inclined surface 82a) of the motor output shaft 3 and the inclined surface 81a of the hold tip 62, and pushes the motor output shaft 3 downward in FIG. This force causes friction between the motor output shaft and the bearing metal 61 to prevent the motor output shaft 3 from rotating in the arrow P direction. Further, in this embodiment, the clutch ball 63 is a ferromagnetic material, and the magnets 91, 92 embedded in the hold tip 62,
The motors 93, 94 are configured so that the motor output shaft 3 and the clutch ball 63 do not come into contact with each other when the motor output shaft 3 rotates in an unregulated direction.

In FIG. 32, when the motor output shaft 3 moves to the right side and the motor output shaft 3 rotates in the direction of the arrow O, the clutch ball 63 moves toward the end side indicated by the reference numeral 85, as shown in FIG. It moves while rotating and is attracted and fixed by the magnet 91. At this time, the motor output shaft 3 is attached to the right stopper 9
5, the clutch ball 63 is attracted to the magnets 91 and 92, and the clutch ball 63 is not in contact with the motor output shaft 3. Reach the black state.

Next, when the motor output shaft 3 moves to the left, conversely to the above, when the motor output shaft 3 rotates in the direction of the arrow O, the clutch ball 63 engages with the groove of the motor output shaft 3. It is sandwiched between 64 (the inclined surface 82a) and the inclined surface 81b of the hold tip 62 to prevent the motor output shaft 3 from rotating in the direction of arrow O, and when the motor output shaft rotates in the direction of arrow P. , Clutch ball 63 is magnet 93 and 94
Is attracted to the motor output shaft 3 and is not in contact with the motor output shaft 3. As a result, when the motor is driven to rotate the motor output shaft 3, the clutch balls 63 can be prevented from sliding, so that noise can be eliminated and durability can be improved.

[0081]

According to the present invention, with a simple structure, the rotation shaft on the output side is prevented from reversing due to the force from the side to which the rotation is transmitted, and the rotation transmission efficiency during normal operation is kept high. can do.

[Brief description of drawings]

FIG. 1 is a schematic diagram in which a reverse rotation preventing bearing device is used in a worm speed reducer specifically showing claim 1.

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

3 is a cross-sectional view taken along the line AA of FIG.

FIG. 4 is an enlarged sectional view of an essential part showing a state where no load is applied to the bearing side.

5 is a sectional view taken along line BB of FIG.

FIG. 6 is an enlarged cross-sectional view of a main part similar to FIG. 2 showing another embodiment.

FIG. 7 is an enlarged cross-sectional view of a main part similar to FIG. 2 showing another embodiment.

FIG. 8 is an enlarged cross-sectional view of a main part similar to FIG. 2 showing another embodiment.

FIG. 9 is a schematic view in which a reverse rotation preventing bearing device is used on both sides.

FIG. 10 is an enlarged cross-sectional view of a main part similar to FIG. 2 showing another embodiment.

FIG. 11 is an explanatory diagram of an angle of a tapered portion.

FIG. 12 is a schematic diagram in which a reverse rotation preventing bearing device is used in a worm speed reducer specifically showing claim 2.

13 is an enlarged cross-sectional view of a main part of FIG.

FIG. 14 is a diagram illustrating the shape of a hold chip.

FIG. 15 is a perspective view of a hold chip.

FIG. 16 is a plan view of a hold chip.

17 is a cross-sectional view taken along the line CC of FIG.

18 is a cross-sectional view taken along the line DD of FIG.

19 is a sectional view taken along line EE of FIG.

20 is a sectional view taken along line FF of FIG.

FIG. 21 is a plan view showing a state in which no load is applied.

FIG. 22 is a plan view showing a state in which no load is applied.

FIG. 23 is a plan view showing a state in which a load is applied.

FIG. 24 is a plan view showing a state in which a load is applied.

FIG. 25 is an operation explanatory view corresponding to the GG section in FIG. 21;

FIG. 26 is an operation explanatory view corresponding to the HH cross section of FIG. 22;

FIG. 27 is an operation explanatory view corresponding to the II cross section of FIG. 23;

FIG. 28 is an operation explanatory view corresponding to the JJ cross section of FIG. 24;

FIG. 29 is an explanatory diagram showing a state in which a load is applied.

FIG. 30 is an explanatory diagram showing a state in which no load is applied.

FIG. 31 is an explanatory view similar to FIG. 29, showing another embodiment.

FIG. 32 is an explanatory diagram showing another embodiment.

FIG. 33 is an explanatory diagram showing the operation of the embodiment of FIG. 32.

FIG. 34 is an explanatory diagram showing an operation as seen from the line KK of FIG. 33.

FIG. 35 is an explanatory diagram showing an operation seen from the line LL in FIG. 34.

[Explanation of symbols]

 2 Motor 3 Motor output shaft 4 Reduction gear 5 Worm 6 Worm wheel 6a Output shaft 10,10 'Reverse rotation prevention bearing device 11,51 Tapered part 11a Recessed part 12 Bearing part (clutch ball) 13 Tip receiving part 13b Sphere (ball) 14 Clutch Ball holding portion 15 Clutch housing 15a Rolling surface 15b Stopper surface 15c Bottom surface 15d Hole 15e Inner wall surface 21 Clutch receiver 22 Spring receiver 23, 24 Coil spring 25 Support plate 31 Step 33 33 Leaf spring 34 Leaf spring 41 Bearing portion (taper roller) 42 Rotation hold Shaft 50 Metal bearing 61 Bearing part (bearing metal) 62 Restricting member (hold tip) 63 Sphere (clutch ball) b, c, d, e, f Clutch surface 64, 64a, 64b Groove 81a, 81b Inclined surface 82a, 82b Inclined Surface 82c plane portion 9 1,92,93,94 Magnet 95 Stopper

Claims (2)

[Claims] 1. A bearing device used in a worm speed reducer, comprising: a worm wheel connected to an output side; and a motor output shaft to which a worm that meshes with the worm wheel is attached. A one-way clutch function for restricting the rotation of the motor output shaft according to a combination condition of the thrust load applied to the output shaft on the bearing device side and the rotation direction of the motor output shaft is provided, and the one-way clutch function is applied to the motor output shaft. A reverse rotation preventing bearing device, characterized in that the formed taper portion and the bearing portion formed on the bearing device contact each other to regulate the rotation of the motor output shaft. 2. A bearing device used in a worm speed reducer, comprising: a worm wheel connected to an output side; and an output shaft to which a worm that meshes with the worm wheel is attached. A one-way clutch function of restricting the rotation of the output shaft according to a combination condition of the thrust load applied to the bearing device side and the rotation direction of the output shaft, and the one-way clutch function includes a groove formed in the output shaft. A rotation prevention of the output shaft by a sphere that comes into contact with the groove and rotates, and a regulation member that has a tapered portion on both inner wall surfaces and that regulates the movement of the sphere by the tapered portion. Bearing device.