JP2001032859A - One-way rotating damper - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a one-way rotating damper with no abrasion and chattering of a rotating member, relaxing concentrated stress an outer ring and providing certain clutch operation which is not influenced by surface roughness of the rotating member. SOLUTION: This one-way rotating damper is constituted of viscous fluid filled in a housing inside chamber 2, an outer ring 4 stored in the inside chamber, a shaft member 6 stored inside of the outer ring and a needle roller 7 supported on the shaft member and free to rotate along an outer ring inner peripheral surface 4a, a projected vane 5 is provided on an outer peripheral surface in the outer ring axial direction, an engagement recessed part is provided on an inner peripheral surface, first and second engagement parts along the axial direction of an opposed end part in the peripheral direction and an elastic means 8 to energize the needle roller on an outer ring inner peripheral surface are installed on the shaft member, and the shaft member receives braking force at the time of rotating in one direction and it rotates without receiving the braking force at the time of rotating in the other direction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a one-way rotary damper, for example, mounted on a roll blind device for absorbing impact at the end of winding or rewinding of a blind.

[0002]

2. Description of the Related Art Conventionally, the end of winding up a blind which has been closed (winding up a blind in a blind accommodating portion) or rewinding an opened blind (sending out a blind which has been wound up from a blind accommodating portion). In order to prevent impact noise and damage to the device, a latch-type one-way rotary damper is used by attaching it to a roll blind or the like. However, such a latch-type one-way rotary damper is large and requires a large number of parts, and thus is not suitable for simple applications. In addition, since the sound generated by the latch action causes discomfort depending on the place of use, there is also an inconvenience that the place of use such as a roll blind equipped with such a damper is restricted.

In order to solve such inconveniences, for example, Japanese Patent Application Laid-Open No. 9-177857 discloses a one-way rotary damper in which a one-way clutch is operated in a closed chamber filled with a high-viscosity fluid. See FIG. 13). In this damper, the outer ring 3
04 and the input shaft 30
6, the roller 307 is engaged or disengaged with a wedge-shaped gap formed between the input shaft 306 and the outer ring 304.
And transmits or cuts off the rotational torque. When rotational torque is transmitted (rotation in the X direction in the figure),
Since the input shaft 306 and the outer ring 304 are integrally rotated relative to the housing 302, viscous shear resistance by the high-viscosity fluid 309 acts on the input shaft 306 to apply a braking force. On the other hand, when the rotation torque is interrupted (rotation in the Y direction in the figure), the input shaft 306 is
4 and the housing 302 through the high-viscosity fluid 309.

However, in such a one-way rotary damper, when the input shaft 306 rotates in the direction in which the rotational torque is transmitted (the X direction in the figure), the outer peripheral surface of the roller 307 becomes the inner peripheral surface of the outer ring 304. Since the outer ring 304 is in linear contact with the outer ring 304, the outer ring 304 is liable to be worn, and the outer ring 304 is easily damaged. Also,
The input shaft 3 is moved in the direction in which the rotational torque is interrupted (Y direction in the figure).
When the roller 06 rotates, the roller 307 is separated from the wedge-shaped gap and is in a free state, so that there is a disadvantage that noise and uneven wear due to chattering easily occur.

Further, the outer peripheral surface of the input shaft 306, the roller 3
There is also a drawback that the magnitude of the generated rotational torque varies or varies depending on the surface roughness of the outer peripheral surface of the outer ring 07 and the inner peripheral surface of the outer ring 304.

In the case where the highly viscous fluid 309 leaks from between the outer ring 304 and the housing 302 and adheres to the outer peripheral surfaces of the input shaft 306 and the roller 307, the rotational torque is transmitted in the direction in which the rotational torque is transmitted. Even when the input shaft 306 rotates, there is also a disadvantage that the clutch function is not reliably exhibited because the outer peripheral surfaces slide.

[0007]

Therefore, the rollers and the outer ring are hardly worn out, the concentrated stress on the outer ring is relieved, there is no chattering of the rollers, and the input shaft, the rollers and the outer rings are not affected by the surface roughness. There has been a demand for a one-way rotary damper that can provide a reliable clutch action.

[0008]

To solve the above-mentioned problems, a one-way rotary damper according to the present invention is characterized in that:
A housing having a chamber therein, a viscous fluid filled in the chamber, an outer ring housed in the chamber, and a shaft member partially housed inside the outer ring and rotatable relative to the housing And a needle roller supported by the shaft member and rotatable along the inner peripheral surface of the outer ring, wherein the outer ring has a radially outer peripheral surface along the axial direction of the outer peripheral surface. A protruding blade is provided that protrudes toward the outer side and an outer end surface of which is in sliding contact with the inner peripheral surface of the housing, and an engaging concave portion that engages with the outer surface of the needle roller is provided along an axial direction of the inner peripheral surface; The shaft member is provided with first and second engagement portions that engage with the outer surface of the needle roller along the axial direction of the end portion facing in the circumferential direction. For biasing against the inner circumference When the shaft member rotates in one direction, the needle roller is supported between the engagement concave portion of the outer race and the first engagement portion of the shaft member while the shaft member rotates in one direction. When the needle roller and the outer ring rotate integrally in the one direction while receiving a braking force and the shaft member rotates in the other direction, the needle roller engages with the first and second engagements of the shaft member. The shaft member and the needle roller are integrally rotated in the other direction without being subjected to a braking force while being supported by the portion and being urged against the inner peripheral surface of the outer race by the elastic means.

With the above structure, when the shaft member rotates in one direction, the rotational torque of the shaft member is transmitted to the outer ring via the needle roller, and when the shaft member rotates in the other direction. In this case, the rotation torque of the shaft member is not transmitted to the outer race, and the shaft member idles. Further, since the needle roller is also immersed in the viscous fluid, it is possible to prevent a sound generated when the needle roller is pushed by the elastic means and is accommodated in the engagement concave portion on the inner peripheral surface of the outer ring.

According to the second aspect of the present invention, a plurality of the projecting blades are provided at equal intervals on the outer peripheral surface of the outer ring, so that a viscous fluid is generated between the outer end surface of the projecting blade and the inner peripheral surface of the housing. It is possible to increase the shear resistance, the friction resistance, and the like, and increase the braking force acting on the rotation of the shaft member.

According to the third aspect of the invention, a plurality of the engagement recesses are provided at equal intervals on the inner peripheral surface of the outer ring, so that the so-called backlash angle can be adjusted.

According to a fourth aspect of the present invention, the first and second opposed first and second parts are provided.
By providing a plurality of sets of the engaging portions, the number of needle rollers supported therebetween can be increased.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the accompanying drawings. 1 to 10 show a first configuration example of a one-way rotary damper according to the present invention, FIG. 1 is an exploded perspective view of the rotary damper, FIG. 2 is a left side view, and FIG.
4A to 10 are cross-sectional views illustrating the operation of the rotary damper.

As shown in FIGS. 1 and 3, the first embodiment of the present invention
The one-way rotation damper 1 according to the configuration example accommodates an outer ring 4 in a chamber 3 of a housing 2, and further includes a shaft member 6 inside the outer ring 4.
And two needle rollers 7 rotatable along the inner peripheral surface 4a of the outer race 4 are arranged on the outer peripheral surface of the base end 6a, and the needle roller 7 is attached to the inner peripheral surface 4a of the outer race 4. A leaf spring 8 for urging the shaft member 6 is assembled to the shaft member 6, and has a structure in which the entire chamber 3 of the housing 2 is filled with the viscous fluid 9. It was done.

Such a rotary damper 1 is used, for example, by being attached to a roll blind device or the like. As a mounting method, a plurality of engagement projections (not shown) provided on the outer peripheral surface of the housing 2 are fitted into engagement recesses provided on an inner wall of a blind accommodating portion of the roll blind device to form the main body. The housing 2 is fixed, and the other end 6b of the shaft member 6 protruding from the housing 2 is connected to the winding shaft of the roll blind device. Therefore, in this type of damper, the fixed housing 2
Although the shaft member 6 is configured to rotate with respect to the shaft member 6, a structure in which the shaft member 6 is fixed and the housing 2 is rotated may be employed.

The housing 2 has a cylindrical shape with a chamber 3 inside, and one end is closed and the other end is open.
At the center of the inner surface on the closed side, the proximal end 6a of the shaft member 6 is provided.
Is rotatably supported by a support shaft 2b.

Outer ring 4 housed in chamber 3 of housing 2
Has two protruding blades 5 protruding radially outward along the axial direction of the outer peripheral surface 4c. These protruding blades 5
It is arranged at a position facing the axis O. Protruding blade 5
Between the outer end surface 5a and the inner peripheral surface 2a of the housing 2.
There is a slight gap that serves as a bypass for the viscous fluid 9, and the outer end surface 5 a of the projecting blade 5 is
a. Instead of the above-mentioned projecting blades, a ring-shaped projecting body that projects radially outward over the entire circumferential direction of the outer ring 4 and has a predetermined length in the axial direction is fitted to the outer peripheral surface of the outer ring 4. May be used.

As shown in FIG. 4, the inner peripheral surface 4a of the outer race 4 has an engagement recess 4 which engages with the outer peripheral surface 7a of the needle roller 7.
Two b are provided along the axial direction. These engaging recesses 4b are also arranged at positions facing the axis O, similarly to the protruding blades 5. The engagement concave portion 4b has a concave surface having a shape complementary to about 1/3 of the outer peripheral surface 7a of the needle roller 7.

As shown in FIG. 1, the shaft member 6 has a base end 6a housed inside the outer race 4 and another end 6b penetrating through the cap 10 and protruding to the outside. The base end 6a
It comprises a flange portion 11 in contact with the cap 10 and a half-split cylindrical portion 12 split in half in the axial direction. In order to prevent the leakage of the viscous fluid 9, an O-ring 13 a is mounted between the end of the other end 6 b on the base end 6 a side and the cap 10. In between, O
-The ring 13b is mounted.

As shown in FIG. 4, at one end in the circumferential direction of the half cylindrical portion 12, a concave surface having a shape complementary to about 1/4 of the outer peripheral surface 7a of the needle roller 7 is formed. A first engaging portion 12a that engages with and supports the outer peripheral surface 7a of the needle roller 7 is formed along the axial direction. On the other hand, the other end in the circumferential direction of the half-split cylindrical portion 12 is formed in a tapered shape along the axial direction, and this tapered portion engages with and supports the outer peripheral surface 7 a of the needle roller 7. The second engaging portion 12b is formed.

The first engagement portion 12a provided on one of the two half-cylinder portions 12 is connected to the second engagement portion 12a of the other half-cylinder portion 12.
The second engaging portion 12b of one half-cylindrical portion 12 is opposed to the engaging portion 12b in the circumferential direction.
The second first engaging portion 12a is disposed so as to face in the circumferential direction. Also, the first engaging portion 1 of each half-cylindrical portion 12
The first half of the other half of the cylindrical portion is provided on the inner peripheral surface near 2a.
Spring support protrusion 12 protruding inward toward engagement portion 12a
c are provided respectively.

A leaf spring 8 having a substantially S-shaped cross section is provided so as to be bridged between two half-split cylindrical portions 12. The S-shaped leaf spring 8 includes horizontal portions 8a, 8a, vertical portions 8b, 8b, ends 8c, 8c, and a central portion 8d. Horizontal part 8
The a and 8a are supported on the inner surfaces of the ends of the half cylinder portions 12 on the first engagement portion 12a side. The vertical portions 8b, 8b are supported on the back surface on the axial center O side of the respective spring support protrusions 12c. The end portions 8c, 8c are supported by the second engagement portions 12b, which are the tapered portions of the half-cylindrical cylindrical portions 12. FIG.
As shown in FIG. 10, when the needle roller 7 is urged against the inner peripheral surface 4a of the outer race 4 by the leaf spring 8, the needle roller 7 is supported by the horizontal portion 8a of the leaf spring 8. ing.

The one-way rotary damper 1 configured as described above
Works as follows. First, FIG. 4 shows that the shaft member 6 is rotated clockwise in the figure in the housing 2 fixed to an external member such as a blind accommodating portion of the roll blind device so that the engagement recess 4 b of the outer ring 4 and the shaft member 6 are rotated. This is a state in which the needle roller 7 is supported between the first engagement portions 12a.

When the shaft member 6 is further rotated clockwise in the figure from the state shown in FIG. 4, the needle roller 7 is sandwiched between the engagement recess 4b of the outer ring 4 and the first engagement portion 12a of the shaft member 6. Meanwhile, the shaft member 6, the needle roller 7, and the outer ring 4 rotate clockwise as a unit, and the rotational torque of the shaft member 6 is transmitted to the outer ring 4 (see FIG. 5). Here, the outer ring 4 is configured such that the outer end surface 5 a of the protruding blade 5 is
a, a shear resistance, a friction resistance, and the like are generated in the viscous fluid 9 interposed in the bypass passage between the outer end surface 5a of the protruding blade 5 and the inner peripheral surface 2a of the housing 2.
These resistances act as a braking force against the rotation of the shaft member 6.

According to the present invention, when the shaft member 6 rotates in the direction in which the braking force acts as described above, the outer peripheral surface 7a of the needle roller 7 is in contact with the engaging recess 4b of the outer ring 4 and the shaft member 6 Of the needle roller 7 and the engaging recess 4b.
The surface, the outer peripheral surface 7a and the first engaging portion 12a surface are hardly worn away from each other, and the stress concentrated on the engaging concave portion 4b surface is also reduced.

FIG. 6 shows a state before reaching FIG. 4. While the shaft member 6 is rotated clockwise in FIG. 6 from the state shown in FIG. 6 to the state shown in FIG. The outer ring 4 rotates smoothly without being caught on the inner peripheral surface 4a of the outer race 4 without receiving resistance. During this rotation, the rotation torque of the shaft member 6 is not transmitted to the outer ring 4, so that the outer ring 4 does not rotate with the shaft member 6 and no braking force acts on the rotation of the shaft member 6. The rotation angle during which no braking force is applied is called backlash. In this configuration example, the angle of the backlash is 180 degrees. The backlash angle is reduced by increasing the number of engagement recesses 4b of the outer race 4 and the number of the needle rollers 7.

In order to use such a one-way rotary damper by attaching it to a blind or the like of a type which performs winding and rewinding manually, the rewinding direction of the winding shaft of the blind is shown in FIGS. By making the shaft member 6 coincide with the clockwise direction in the drawing, a braking force can be applied at the time of rewinding. This can prevent the front end portion of the blind from vigorously colliding with the window frame or the like at the end of the rewinding.

On the other hand, in order to use it by attaching it to a blind or the like of a type that performs winding and rewinding using a spring means,
By making the winding direction of the winding shaft of the blind coincide with the clockwise direction of the shaft member 6 shown in FIGS. 4 to 6 in the drawings, a braking force can be applied at the time of winding. Thus, it is possible to prevent the front end of the blind from vigorously colliding with the blind accommodating portion or the like at the end of the winding.

Next, a case where no braking force acts on the rotation of the shaft member 6 will be described. When the shaft member 6 is slightly rotated counterclockwise in the figure from the state shown in FIG. 4, as shown in FIG. 7, a second tapered second member provided at the other end in the circumferential direction of the half-cylindrical portion 12 is formed. The tip of the engagement portion 12b contacts the outer peripheral surface 7a of the needle roller 7.

When the shaft member 6 is further rotated counterclockwise in the figure from the state shown in FIG. 7, the needle roller 7 is pushed by the tip of the taper and the leaf spring 8 is an elastic means.
While being urged against the inner peripheral surface 4a of the outer race 4 by rotation, it rotates with the shaft member 6 while rotating and reaches the state shown in FIG. FIG. 8 shows that the needle roller 7 is pinched between the second engaging portion 12b of one half-cylindrical portion 12 and the end of the first engaging portion 12a formed on the other half-cylindrical portion 12. And a state in which the inner peripheral surface 4a of the outer race 4 is urged by the leaf spring 8.

When the shaft member 6 is further rotated counterclockwise in the figure from the state shown in FIG. 8, the needle roller 7 rotates together with the shaft member 6 while rotating, while maintaining the state shown in FIG. The state shown in FIG.

When the shaft member 6 is slightly rotated counterclockwise in the figure from the state shown in FIG. 9, the needle roller 7 is accommodated in the engagement recess 4b of the outer ring 4 as shown in FIG.
To the same state as. When the shaft member 6 is further rotated counterclockwise in the figure from this state, the states of FIGS. 7 to 10 are repeated.

While the shaft member 6 is rotating to the state shown in FIGS. 4 and 7 to 10, the needle roller 7 does not get caught on the inner peripheral surface 4a of the outer race 4 along the inner peripheral surface 4a. Since the shaft member 6 rotates smoothly without receiving a resistance force, the rotation torque of the shaft member 6 is not transmitted to the outer ring 4. Therefore, only the shaft member 6 supporting the needle roller 7 rotates and the outer ring 4 does not rotate, so that no braking force acts on the rotation of the shaft member 6.

According to the present invention, when the shaft member 6 rotates in the direction in which the braking force does not act as described above, the needle roller 7 engages with the second engaging portion 1 of the one half cylindrical portion 12.
2b and an end of a first engagement portion 12a formed in the other half-cylindrical portion 12, and is urged by a leaf spring 8 against the inner peripheral surface 4a of the outer race 4; There is no rattling. Therefore, noise and uneven wear due to chattering do not occur.

In order to use such a one-way rotary damper by attaching it to a blind or the like of a type of manually winding and rewinding, the winding direction of the winding shaft of the blind is shown in FIGS. By making the shaft member 6 coincide with the counterclockwise direction in the drawing, the blind can be easily wound without receiving a resisting force without applying a braking force at the time of winding.

On the other hand, when such a one-way rotary damper is used by being mounted on a blind or the like of a type that performs winding and rewinding using a spring means, the rewinding direction of the winding shaft of the blind is shown in FIG. When the shaft member 6 shown in FIGS. 7 to 10 is made to coincide with the counterclockwise direction in the drawing, the blind can be easily rewound without receiving a resistance force without applying a braking force at the time of rewound.

In the one-way rotary damper of the present invention, the shaft member 6
Is rotated in either direction, the needle roller 7 is connected to the inner peripheral surface 4 a of the outer race 4 and the engagement portion 12 of the shaft member 6.
Since they are supported by a, 12b, etc., the magnitude of the generated rotational torque does not change or vary depending on the surface roughness of each of these surfaces. Further, since the needle roller 7 itself is immersed in the viscous fluid 9, the sound generated when the needle roller 7 is housed in the engagement recess 4 b of the outer peripheral surface 4 a is absorbed and silenced by the viscous fluid 9. There are also advantages.

Next, another configuration example of the one-way rotary damper according to the present invention will be described. In these configuration examples, only portions different from the first configuration example will be described.

FIG. 11 is a cross-sectional view of a second configuration example of the one-way rotary damper according to the present invention. In the one-way rotary damper 101 of this configuration example, four projecting blades 105 are provided at equal intervals on the outer peripheral surface 104c of the outer ring 104, and the engaging concave portions 104b are spaced at equal intervals along the axial direction of the inner peripheral surface 104a of the outer ring 104. Are provided.

The protruding blade 105 used in this configuration example
Has the same shape as that used in the first configuration example. Therefore, the total area of the outer end surface 105a that slides on the inner peripheral surface 102a of the housing 102 increases as the number of the used protruding blades 105 increases. As a result, the shear resistance, friction resistance, and the like generated in the viscous fluid 109 interposed in the bypass between the outer end surface 105a and the inner peripheral surface 102a of the housing 102 also increase in proportion to the increase in the area of the outer end surface 105a. Therefore, based on these resistance forces, the shaft member 1
The braking force acting on the rotation of 06 also increases accordingly. A one-way rotary damper capable of obtaining such a strong braking force is suitably used for a large roll blind or the like.
Further, by appropriately selecting the number of the protruding blades 105 and the area of the outer end surface 105a, it is possible to adjust the obtained braking force.

In this configuration example, the inner peripheral surface 10
Since six engagement recesses 104b are provided at equal intervals along the axial direction of 4a and two needle rollers 107 are used, the above-described backlash angle is 60 degrees.
Thus, the backlash angle can be reduced by increasing the number of the engagement recesses 104b.

FIG. 12 is a cross-sectional view of a third configuration example of the one-way rotary damper according to the present invention. In the unidirectional rotary damper 201 of this configuration example, four needle rollers 207 are used so as to be symmetrical with respect to the axis O, and the outer ring 204 is used.
Six engagement recesses 204b are provided at equal intervals along the axial direction of the inner peripheral surface 204a. In this configuration example, the number of the needle rollers 207 is two more than in the second configuration example, and the backlash angle is １ ／ of that in the second configuration example.
Of 30 degrees. Thus, the backlash angle can also be reduced by increasing the number of the needle rollers 207.

In this configuration example, the base end 2 of the shaft member 206
Reference numeral 06a is composed of four quartered cylindrical portions 212 divided in the axial direction. In addition, two leaf springs 208 are used to bias the four needle rollers 207 against the inner peripheral surface 204a of the outer ring 204, and the two needle rollers 207 are supported by each leaf spring 208. Has become.

As in the first configuration example, each quarter cylindrical part 2
Twelve first engaging portions 212a are circumferentially opposed to second engaging portions 212b of the adjacent quartered cylindrical portion 212,
The second engagement portion 212b of each quarter cylinder portion 212 is disposed so as to face the first engagement portion 212a of the adjacent quarter cylinder portion 212 in the circumferential direction. In addition, spring support protrusions 212c are provided on the inner peripheral surface of each quarter cylinder portion 212 near the first engagement portion 212a, and each spring support protrusion 212c extends with each adjacent spring support protrusion 212c. It projects in a direction substantially orthogonal to the line.

Two leaf springs 2 having an S-shape with a distorted cross section
08 and 208 are adjacent three quarter cylinder portions 212.
Are arranged so as to be bridged to each other. Leaf spring 20
8 is a horizontal portion 208a, a central horizontal portion 208d, a vertical long portion 208b, a vertical short portion 208b ', and end portions 208c and 208.
c. The vertically long portion 208b and the horizontal portion 208a are supported on the inner surfaces of the ends of the adjacent quartered cylindrical portion 212 on the first engagement portion 212a side. The vertical short portion 208b 'and the central horizontal portion 208d are connected to the adjacent quartered cylindrical portion 212.
Are supported on the back surface on the axial center O side of each of the spring support protrusions 212c. End 208c on the side of vertical long portion 208b
Are supported by the second engagement portion 212b formed of the tapered portion of the remaining quarter cylinder portion 212 among the three. The central horizontal portion 208d is supported by the central shaft 206c.

The needle roller 20 is moved by the leaf spring 208.
When 7 is urged to the inner week surface 204a of the outer ring 204,
The two needle rollers 207 are supported by a horizontal portion 208a and a vertically long portion 208b of the leaf spring 208, respectively.

[0047]

According to the first aspect of the present invention, there is provided a rotary damper having a housing having a chamber therein, a viscous fluid filled in the chamber, an outer ring accommodated in the chamber, and A one-way rotation damper including a shaft member partially housed and rotatable relative to the housing, and a needle roller supported along the shaft member and rotatable along an inner peripheral surface of the outer ring. The outer race is provided with protruding blades that protrude radially outward along the axial direction of the outer peripheral surface and whose outer end surface is in sliding contact with the inner peripheral surface of the housing, and along the axial direction of the inner peripheral surface. An engagement concave portion is provided for engaging with the outer surface of the needle roller. The shaft member has first and second engagement portions that engage with the outer surface of the needle roller along the axial direction of the end portion facing in the circumferential direction. Engaging portions are provided, respectively, and An elastic means for urging the needle roller against the inner peripheral surface of the outer ring is attached, and when the shaft member rotates in one direction, the needle roller is engaged with the engagement recess of the outer ring and the shaft member. While being supported between the first engagement portion, the shaft member, the needle roller and the outer ring rotate integrally in the one direction while receiving a braking force, and when the shaft member rotates in the other direction, The shaft member and the needle roller receive a braking force while the needle roller is supported by the first and second engagement portions of the shaft member and is urged by the elastic means against the inner peripheral surface of the outer ring. Instead, they are integrally rotated in the other direction.

By mounting the one-way rotary damper thus configured on a roll blind, for example,
When the shaft member of the damper rotates in one direction, the rotational torque of the shaft member is reliably transmitted to the outer ring via the needle roller, so that the impact at the end at the time of winding or rewinding the blind is reduced. Can be absorbed. Also, when the shaft member rotates in the other direction, the rotational torque of the shaft member is not transmitted to the outer ring, so that the blind is manually wound up,
Alternatively, when the blind is rewound by the spring force, the blind can be easily wound and rewound without receiving the braking force.

Since the entire interior of the housing is filled with the viscous fluid, the needle roller is also immersed in the viscous fluid. Therefore, since the sound generated when the needle roller is pushed by the elastic means and is housed in the engagement concave portion of the inner peripheral surface of the outer ring is absorbed by the viscous fluid and is silenced,
It is suitably used when such a sound is disliked as causing discomfort.

According to a second aspect of the present invention, a plurality of the protruding blades are provided at equal intervals on the outer peripheral surface of the outer ring, so that the viscosity interposed in the bypass between the outer end surface of the protruding blade and the inner peripheral surface of the housing is increased. The shear resistance, friction resistance, etc. generated in the fluid increase. When such resistance increases, the braking force acting on the rotation of the shaft member also increases. Therefore, it can be suitably used for a large roll blind or the like that requires a large braking force. Further, by selecting the number of the protruding blades to be used, the obtained braking force can be adjusted.

According to a third aspect of the present invention, a plurality of the engagement recesses are provided at equal intervals on the inner peripheral surface of the outer ring. By providing a large number of engagement concave portions, it is possible to reduce the so-called backlash angle at which no braking force acts. The backlash angle can be adjusted by appropriately selecting the number of engagement recesses.

According to the fourth aspect, the first and second opposed first and second elements are provided.
Are provided in plural sets. Thereby, the number of needle rollers supported between the first and second engagement portions can be increased, and the angle of backlash can be reduced. The backlash angle can be adjusted by appropriately selecting the number of needle rollers.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of a first configuration example of a one-way rotary damper according to the present invention.

FIG. 2 is a left side view of the one-way rotary damper according to the first configuration example.

FIG. 3 is a sectional view taken along line AA of FIG. 2;

FIG. 4 is a cross-sectional view taken along the line BB of FIG. 3, and is an explanatory diagram showing an operation of the one-way rotary damper according to the first configuration example.

FIG. 5 is an explanatory diagram showing an operation of the one-way rotary damper according to the first configuration example.

FIG. 6 is an explanatory diagram showing an operation of the one-way rotary damper according to the first configuration example.

FIG. 7 is an explanatory diagram showing an operation of the one-way rotary damper according to the first configuration example.

FIG. 8 is an explanatory diagram illustrating an operation of the one-way rotation damper according to the first configuration example.

FIG. 9 is an explanatory diagram showing an operation of the one-way rotary damper according to the first configuration example.

FIG. 10 is an explanatory diagram showing an operation of the one-way rotation damper according to the first configuration example.

FIG. 11 is a cross-sectional view of a second configuration example of the one-way rotary damper according to the present invention.

FIG. 12 is a cross-sectional view of a third configuration example of the one-way rotary damper according to the present invention.

FIG. 13 is a partial cross-sectional view of a conventional one-way rotary damper.

[Explanation of symbols]

1,101,201 ... one-way rotary damper, 2,102
··· Housing, 3 ·· Room, 4,104,204 ··· Outer ring, 4a, 104a, 204a ··· Inner peripheral surface, 4b, 10
4b, 204b, engagement recess, 5, 105, projecting blade, 6, 206, shaft member, 7, 107, 207, needle roller, 8, 208, elastic means, 9, 109
.Viscous fluid, 12a, 212a.
b, 212b... second engagement portion.

Claims (4)

[Claims] 1. A housing having a chamber therein, a viscous fluid filled in the chamber, an outer ring housed in the chamber, and a partly housed interior of the outer ring and a relative rotation with respect to the housing. A one-way rotation damper comprising a possible shaft member and a needle roller rotatable along an inner peripheral surface of the outer ring while being supported by the shaft member, wherein the outer ring has an axial direction of an outer peripheral surface. An engaging recess that is provided with a protruding blade that protrudes radially outwardly and whose outer end surface is in sliding contact with the inner peripheral surface of the housing, and that engages with the outer surface of the needle roller along the axial direction of the inner peripheral surface. The shaft member is provided with first and second engagement portions that engage with the outer surface of the needle roller along the axial direction of the end portions facing each other in the circumferential direction, and the needle Roller against the inner peripheral surface of the outer ring When the shaft member rotates in one direction, the needle roller is supported between the engagement recess of the outer race and the first engagement portion of the shaft member. When the shaft member, the needle roller, and the outer ring rotate integrally in the one direction while receiving a braking force, and when the shaft member rotates in the other direction, the needle roller is first and the second of the shaft member. 2 supported by the engaging portion,
A one-way rotation damper, wherein the shaft member and the needle roller rotate integrally in the other direction without receiving a braking force while being urged against the inner peripheral surface of the outer ring by the elastic means. 2. The one-way rotary damper according to claim 1, wherein a plurality of the protruding blades are provided at equal intervals on an outer peripheral surface of the outer ring. 3. The one-way rotary damper according to claim 1, wherein a plurality of the engagement concave portions are provided at equal intervals on an inner peripheral surface of the outer ring. 4. The one-way rotary damper according to claim 1, wherein a plurality of sets of the first and second engaging portions facing each other are provided.