JP3280941B2 - Rotary damper - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary damper in which the rotation speed is suppressed to a low speed by utilizing the flow resistance of a fluid.

[0002]

2. Description of the Related Art A conventional rotary damper of this type is disclosed, for example, in JP-A-10-292723. The rotary damper includes a damper body having a fitting hole,
A rotating body having a shaft portion rotatably inserted into the fitting hole, and a housing chamber is formed between an inner peripheral surface of the fitting hole and an outer peripheral surface of the shaft portion. Both ends of this containment chamber
Each of the partition walls is closed, and one of the partition walls has a cutout penetrating therethrough. A fluid such as a viscous fluid or the like is filled from the notch into the housing chamber. After the fluid is filled, a seal member such as an O-ring is mounted between the inner peripheral surface of the fitting hole adjacent to each partition wall and the outer peripheral surface of the shaft. This prevents the fluid in the storage chamber from leaking to the outside.

[0003] The accommodation chamber is divided into first and second chambers in the circumferential direction by a partition wall formed on the inner peripheral surface of the fitting hole and a wing formed on the outer peripheral surface of the shaft. It is divided into rooms. In the first and second chambers, when the rotating body rotates, one internal volume decreases, and the other internal volume increases. As a result, fluid flows from one chamber having a reduced internal volume to the other chamber having an increased internal volume.

[0004] A resistance generator is provided between the first chamber and the second chamber. The resistance generating unit includes, for example, an orifice, and generates a resistance having a magnitude corresponding to a flow rate of the fluid per unit time. Therefore, when the rotating body tries to rotate at high speed, the resistance generating section generates a large resistance. Thereby, the rotation speed of the rotating body can be suppressed to a low speed.

[0005]

In the above-mentioned conventional rotary damper, there is a problem that the fluid filled in the storage chamber leaks outside. Upon studying this problem, it was found that the cause was due to deformation of the sealing member. That is, it is assumed that the fluid is now flowing from the first chamber to the second chamber in the conventional rotary damper. In this state, the internal pressure of the second chamber becomes a negative pressure. When the pressure in the second chamber becomes negative, a part of the seal member is sucked into the second chamber through the notch, and is greatly deformed. As a result, the contact surface pressure between the seal member and the inner peripheral surface of the fitting hole and the outer peripheral surface of the shaft portion decreases, and there is a possibility that the fluid in the storage chamber leaks to the outside. In addition, since the seal member is deformed each time the rotating body is repeatedly rotated and stopped, the seal member is deteriorated early, the sealing property is reduced, and the fluid in the storage chamber leaks to the outside.

[0006]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a damper body having a fitting hole and a rotating body having a shaft rotatably inserted into the fitting hole. And between the inner peripheral surface of the fitting hole and the outer peripheral surface of the shaft portion, both ends are respectively closed by partition walls, and annular storage chambers filled with fluid are formed. A seal member made of an elastic material for preventing fluid in the accommodation chamber from leaking to the outside is provided adjacent to the partition wall part, and an inner peripheral surface of the fitting hole facing the accommodation chamber and the shaft part are provided. One and the other of the outer peripheral surface are provided with a blade portion and a partition wall portion for partitioning the storage chamber into a first chamber and a second chamber in a circumferential direction thereof, respectively. The fluid flows between the second chamber and the second chamber when the rotating body rotates in at least one direction. A resistance generating portion is provided to allow a resistance to flow from the first chamber to the second chamber, and at least one of the partition walls is formed with a notch for filling the storage chamber with a fluid. In the rotary damper described above, a rigid ring member is disposed between the one partition wall in which the notch is formed and the seal member.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to FIGS. 1 and 2 show an embodiment of the present invention. The rotary damper 1 of this embodiment is provided between a toilet body (body) and a toilet lid (door) of a toilet seat in order to close and rotate the toilet lid at a low speed. It has a body 3. Of course, the rotary damper of the present invention can be used for applications other than a damper hinge for a toilet seat.

The damper body 2 has a cylindrical shape, and has a fitting hole 21 that penetrates a central portion thereof. On the inner peripheral surface of the fitting hole 21, a screw hole 21a is formed at one end (right end), and a support hole 21b is formed at the other end. The intermediate member 4 is non-rotatably fitted to one end of the fitting hole 21. The intermediate member 4 is prevented from coming off by the screw member 5 screwed and fixed to the screw hole 21a.

The rotating body 3 has a shaft portion 31 rotatably inserted into the fitting hole 21 and a connecting portion 32 protruding from the fitting hole 21. The journal portion 31a, 31b formed at both ends of the shaft portion 31 is
1b and the intermediate member 4 are rotatably fitted to each other, and are rotatably supported by the damper body 2. In this embodiment, the connecting portion 32 is connected to either the toilet body or the toilet lid. The damper body 2 is connected to either the toilet body or the toilet lid. Thus, the toilet lid is rotatably connected to the toilet body.

The rotating body 3 is inserted into the fitting hole 21 from one end thereof with the connecting portion 32 in front, and a partition wall portion 31c described later is formed on the inner peripheral surface of the fitting hole 21. By hitting the step portion 21c, the fitting hole 21 is prevented from coming off from the fitting hole 21 to the other end (the left end in FIG. 1A).
After the insertion of the rotating body 3, the intermediate member 4 is
1 and the screw member 5 is inserted into the screw hole 2
By being screwed into 1a, the rotation body 3 is prevented from coming off from the fitting hole 21 to one end side.

A coil spring 6 as an elastic member is arranged between the shaft 31 of the rotating body 3 and the intermediate member 4.
One end 61 of the coil spring 6 is connected to the rotating body 3 and the other end 62 is connected to the intermediate member 4. The direction in which the rotating body 3 opens the toilet lid with respect to the damper body 2 (FIG. B)
(Arrow Y direction).

There is a gap between the inner peripheral surface of the fitting hole 21 adjacent to one end side (the right end side in FIG. 1A) of the support hole portion 21b and the outer peripheral surface of the shaft portion 31 opposed thereto. , An annular storage chamber 7 is formed. One end in the axial direction of the storage chamber 7 is closed by an annular partition wall 31 c formed on the outer peripheral surface of the shaft 31. The other end of the storage chamber 7 is closed by a substantial part of the damper main body 2 constituting the support hole 21 and the journal part 31a. Therefore, in this embodiment, the substantial portion and the journal portion 31a that constitute the support hole 21 constitute a partition wall that closes the other end of the storage chamber 7. In order to close the other end of the storage chamber 7, a partition wall similar to the partition wall 31c is
1 may be formed, or two partition walls for closing both ends of the storage chamber 7 may be formed on the inner peripheral surface of the fitting hole 21.

As shown in FIG. 1B, the partition wall portion 31c
Is formed with a cutout portion 31d penetrating therethrough. From the outside through the notch 31d, the accommodation room 7
The inside is filled with a fluid such as a viscous fluid. Of course, the filling of the fluid is performed after inserting the rotating body 3 into the fitting hole 21 and before inserting the intermediate member 4 and the screw member 5 into the fitting hole 21. A seal member 8A such as an O-ring made of an elastic material is mounted between the inner peripheral surface of the fitting hole 21 adjacent to the partition wall portion 31c and the outer peripheral surface of the shaft portion 31. A similar seal member 8B is mounted between the support hole 21b and the journal 31a. The housing chamber 7 is sealed from the outside by these two seal members 8A and 8B.

A blade 31e is formed on the outer peripheral surface of the shaft portion 31 facing the housing chamber 7, and a partition wall portion 21d is formed on the inner peripheral surface of the fitting hole 21 facing the housing chamber 7. I have. The interior of the storage chamber 7 is divided into two parts in the circumferential direction by the blade part 31e and the partition wall part 21d, and is divided into a first chamber 71 and a second chamber 72. The blade part 31e and the partition wall part 21d may be formed at two addresses as shown in FIG. In that case, the first and second chambers 71, 7
2 is also addressed to two. In addition, the wing portion 31
e may be formed on the inner peripheral surface of the fitting hole 21, and the partition wall portion 21 d may be formed on the outer peripheral surface of the shaft portion 31.

The blade 31e is in sliding contact with the inner peripheral surface of the fitting hole 21. Therefore, when the rotating body 3 rotates, first,
The internal volume of one of the second chambers 71 and 72 increases, and the internal volume of the other decreases. Then, the fluid flows from the chamber where the internal volume decreases to the chamber where the internal volume increases. Here, there is a gap between the partition wall portion 21d and the shaft portion 31 through which the fluid can flow without resistance. Therefore, when the rotating body 3 rotates, the fluid in the first and second chambers 71 and 72 can flow through the gap between the partition wall 21d and the shaft 31. However, a one-way valve 9 including a valve chamber 91 formed of a concave portion formed therein and a valve body 92 accommodated in the valve chamber 91 is provided in the partition wall portion 21d. The one-way valve 9 is configured so that the fluid in the second chamber 72
, But prevents the fluid in the first chamber 71 from flowing into the second chamber 72.

Therefore, the fluid in the second chamber 72 can flow into the first chamber 71 without resistance through the space between the partition wall portion 21d and the shaft portion 31. Arrow Y
It can rotate in the direction without resistance. Moreover, the rotating body 3 is urged in the same direction by the coil spring 6.
Therefore, the toilet lid can be opened slightly.

On the other hand, the fluid in the first chamber 71 cannot flow into the second chamber 72 through the space between the partition wall portion 21d and the shaft portion 31, and is fitted to the outer peripheral surface of the blade portion 31e. Hole 21
Flows into the second chamber 72 through a minute gap between the inner peripheral surface of the partition wall 31c and the outer peripheral surface of the partition wall portion 31c and the fitting hole 21.
After once passing through the minute gap between the inner peripheral surface and the seal member 8A side, it flows into the second chamber 72 through the notch 31d. Therefore, when the fluid in the first chamber 71 flows into the second chamber 72, a large resistance is generated. As is clear from this, in this embodiment, the minute gap between the blade portion 31e and the fitting hole 21 and the partition wall portion 31c
The minute gap between the hole and the fitting hole 21 is a resistance generating portion. As the resistance generating portion, an orifice may be provided on the blade portion 31e or the partition wall portion 21d, or other means may be employed.

A large resistance is generated when the fluid flows from the first chamber 71 to the second chamber 72, and the rotating body 3 is urged by the coil spring 6 in the direction of arrow Y in FIG. Therefore, the rotating body 3 cannot rotate at high speed in the direction of the arrow X, and the rotation speed is suppressed to low speed. Therefore, the closing rotation speed of the toilet lid is suppressed to a low speed.

Since there is a flow resistance generating portion between the first chamber 71 and the second chamber 72, when the rotating body 3 rotates in the direction of the arrow X, the inside of the second chamber 72 is under negative pressure. become. Due to this negative pressure, a part of the seal member 8A is sucked into the second chamber 71 through the notch 31d.

In order to prevent such a problem, in the rotary damper 1, the ring member 10 is disposed between the partition wall 31c and the seal member 8A. The ring member 10 has an outer diameter and an inner diameter sufficient to shield the notch 31d and prevent the seal member 8A from directly opposing the notch 31d. In the case of this embodiment, the outer diameter and the inner diameter of the ring 10
Are substantially the same as the outer diameter and the base diameter (the outer diameter of the shaft portion 31 on which the partition wall portion 31c is formed). Therefore, when the seal member 8A is sucked into the second chamber 72 through the notch 31d, the seal member 8A
Hit. The ring member 10 has rigidity enough to prevent at least the deformation of the seal member 8A. Note that the ring member 10 is mounted before or simultaneously with the mounting of the seal member 8A after the housing hole 7 is filled with the fluid.

In the rotary damper having the above structure, the ring member 10 reliably prevents the seal member 8A from being sucked and deformed by the negative pressure in the second chamber 72. Therefore, the contact surface pressure between the seal member 8A and the inner peripheral surface of the fitting hole 21 and the outer peripheral surface of the shaft portion 31 can be maintained at a predetermined set pressure. Therefore, it is possible to prevent the fluid in the storage chamber 7 from leaking to the outside. Moreover, the sealing member 8
A maintains good sealing properties over a long period of time because it is not deformed. Therefore, leakage of the fluid can be reliably prevented for a long period of time.

The present invention is not limited to the above embodiment, but can be modified as appropriate. For example, in the above embodiment, the rotating body 3 is rotationally biased by the coil spring 6 as an elastic member, but the coil spring 6 may not be provided. Although the damper effect is provided only when the rotating body 3 rotates in the X direction, the damper effect is provided when the rotating body 3 rotates in any of the X and Y directions. You may.

[0023]

As described above, according to the present invention, it is possible to prevent the seal member from being deformed by the negative pressure in the storage chamber, so that the fluid filled in the storage chamber leaks to the outside. Can be surely prevented over a long period of time.

[Brief description of the drawings]

FIG. 1 is a view showing an embodiment of the present invention, wherein FIG. 1 (A) is a longitudinal sectional view thereof, and FIG. 1 (B) is a view B of FIG. 1 (A).
It is sectional drawing which follows the -B line.

FIG. 2 is an exploded perspective view showing the same embodiment.

FIG. 3 is a sectional view similar to FIG. 1B, showing another embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Rotary damper 2 Damper main body 3 Rotating body 7 Storage room 8A Seal member 10 Ring member 21 Fitting hole 21d Partition wall 31 Shaft 31c Partition wall 31d Notch 31e Blade 71 First chamber 72 Second chamber

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Ryosuke Bando 1-8-11 Higashikanda, Chiyoda-ku, Tokyo Inside Sugatune Industry Co., Ltd. (72) Inventor Masahiro Yoshida 1- 8-11 Higashikanda, Chiyoda-ku, Tokyo (56) References JP-A-10-292723 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) E05F 3/14 F16F 9/14

Claims (1)

(57) [Claims] 1. A damper body having a fitting hole, a rotating body having a shaft rotatably inserted into the fitting hole, an inner peripheral surface of the fitting hole and an outer peripheral surface of the shaft portion. In between, both ends are closed by partition walls, respectively, and an annular storage chamber filled with fluid is formed, and an elastic material that prevents the fluid in the storage chamber from leaking outside is formed. A sealing member is provided adjacent to the partition wall portion, and one side of the inner peripheral surface of the fitting hole facing the housing chamber and the other of the outer peripheral surface of the shaft portion have the housing chamber surrounding the housing chamber. A vane section and a partition wall section are provided, each of which is divided into a first chamber and a second chamber in the direction, and at least one of the rotating bodies is provided between the first chamber and the second chamber. A resistor that allows the fluid to flow from the first chamber into the second chamber with resistance when rotating in the direction. A rotary damper provided with an anti-producing portion and having a cut-out portion for filling the accommodation chamber with a fluid in at least one of the partition wall portions, wherein one of the partitions having the cut-out portion formed therein; A rotary damper, wherein a rigid ring member is disposed between the wall and the seal member.