JP3485338B2 - Rotary damper - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary damper for applying a braking torque to a rotor. 2. Description of the Related Art A conventional rotary damper fills a working chamber formed in a housing with a viscous fluid, and applies a braking torque to a rotating part rotating in the working chamber of a rotor by viscous resistance of the viscous fluid. Have been. Therefore, when trying to rotate the rotor, a braking torque due to viscous resistance generated between the rotor and the viscous fluid is applied to the rotor, so that the rotation of the rotor can be braked. In a conventional rotary damper, a viscous fluid is sealed in a working chamber using a cap or the like. However, when the viscous fluid leaks at the time of sealing and air enters the working chamber. Thus, a variation occurs in the braking torque. In addition, the leakage of the viscous fluid during use causes the fluctuation of the braking torque and the contamination of the surrounding mechanical parts with the viscous fluid. Furthermore, since sealing must be performed with an O-ring or the like so that the viscous fluid does not leak, there is a disadvantage that the number of steps in assembling increases and the cost increases. SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned disadvantages, and there is no variation and fluctuation in braking torque, there is no contamination of surrounding mechanical parts, the number of assembly steps is reduced, and the cost is reduced. The present invention provides a rotary damper that can be achieved. [0005] According to an aspect of the present invention is filled in the rotary damper for applying braking torque to the rotation of the rotor which rotates at working chamber formed in the housing, the oil compounded rubber granules to create movement chamber And contact the rotating part of the rotor. [0006] [action] rotary damper according to the present invention includes a rotating portion of the rotor, the friction resistance generated between the OIL kneading rubber granular material according to the rotor to brake the rotation of the rotor. An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view showing the configuration of a rotary damper according to a first embodiment of the present invention. In FIG. 1, reference numeral 1 denotes a housing, and a cylindrical housing body 2 having an open upper surface.
And a cap 3 for closing the opening of the housing body 2
It is composed of The housing body 2 is provided with a columnar projection 2bp at the center of the bottom 2b for rotatably supporting a rotor 4 to be described later, and is provided with a recessed portion 2sd which is rotated above the inner peripheral surface of the side wall 2s. Have been. Also, cap 3
A hole 3h through which the shaft 4x of the rotor 4 penetrates is provided at the center, and a ridge 3p that fits into the recess 2sd of the housing body 2 is provided around the circumference or at a predetermined location. The working chamber includes a housing body 2 and a cap 3.
And a space formed by Reference numeral 4 denotes a rotor, and a hole 3h of the cap 3 is provided.
And a flange 4f which is a rotating part provided at the lower end of the shaft 4x. A hole 4xd into which the protrusion 2bp of the housing body 2 is rotatably fitted is provided at the center of the lower surface of the shaft portion 4x. Reference numeral 6 denotes a gear, a rotor protruding from the cap 3.
-4 is attached to the shaft 4x. [0010] 21 is a small oil filled in the working chamber
Shows kneaded rubber granules, for example, adding silicone oil,
Silicone rubber particles with a hardness of 25 or less manufactured by kneading
Body. Next, the assembly will be described. First, a predetermined amount of the oil-kneaded rubber particles 21 is put into the housing body 2 .
After the flange portion 4f inside the housing main body 2 by inserting a portion of the shaft portion 4x, fitting the projections 2bp the holes 4xd. After a predetermined amount of the oil- kneaded rubber particles 21 is further filled on the flange portion 4f , the shaft portion 4x is inserted through the hole 3h, and the cap 3 is pressed into the housing main body 2 to be pressed. 3p to the fitting in the recess 2sd, the flange portion 4f
Oil compounded rubber granules 21 come in contact in a compressed state to the surface. Further, a gear 6 is attached to the shaft 4x protruding from the cap 3.
Is attached, as shown in FIG. Next, the operation will be described. First, when the rotational force is applied and the gear 6 rotates, the rotor 4
Also rotate. Then, the flange portion 4f, since the surface is in contact with the oil compounded rubber granules 21, the flange portion 4f attempts to rotate, the flange portion 4f and OIL compounded rubber
Friction resistance is generated between the granules 21, but kneaded allowed oil (silicone oil) is moderate frictional resistance becomes lubricant (brake torque). Therefore, the flange 4
f, that is, the rotation of the gear 6 can be braked by applying an appropriate braking torque to the rotor 4. As described above, according to the first embodiment, the braking torque is applied to the rotor 4 by the frictional resistance between the flange portion 4f and the oil-kneaded rubber granules 21 contacting the surface of the flange portion 4f. With this configuration, there is no such thing as a viscous fluid that flows out to change the braking torque at the time of assembly, so that there is no variation in the braking torque. And
Since a fluid such as a viscous fluid is not used to apply a braking torque to the flange portion 4f, the viscous fluid does not leak during use, thereby contaminating surrounding mechanical components, and the braking torque does not fluctuate. Further, since there is no need to perform sealing with an O-ring or the like, the number of assembly steps is reduced, and the cost can be reduced. FIG. 2 is a sectional view showing the structure of a rotary damper according to a second embodiment of the present invention. In FIG. 2, 11
Denotes a housing having a cylindrical shape with an open top,
A locking portion 11s protruding inward at a predetermined position at the upper end of 1s.
p is provided. Reference numeral 12 denotes a rotor that also functions as a cap that closes the opening of the housing 11, and includes a shaft portion 12x and a flange portion 12f that is a circular rotating portion formed at the lower end of the shaft portion 12x. A gear 12g is formed integrally with an upper end portion of the shaft portion 12x protruding from the housing 11. The working chamber is a space formed by the housing 11 and the rotor 12. [0015] 21 is a small oil filled in the working chamber
Shows kneaded rubber granules, for example, adding silicone oil,
Silicone rubber particles with a hardness of 25 or less manufactured by kneading
Body . Next, the assembly will be described. First, the housing 11 is filled with a predetermined amount of the oil-kneaded rubber particles 21 . When the flange portion 12f of the rotor 12 is press-fitted into the housing 11 and locked to the locking portion 11sp,
The oil-kneaded rubber particles 21 come into contact with the surface of the flange portion 12f in a compressed state, and can be assembled as shown in FIG. The description of the operation is the same as that described above, and will not be repeated. Also in the second embodiment, the first
An effect similar to that of the embodiment can be obtained. [0017] Incidentally, the oil compounded rubber granules 21 since flange portion 4f, in point contact to 12f applies braking torque to the rotor 4 and 12, it may be small as Braking torque. [0018] As is evident from the foregoing description, according to the present invention, since a configuration for applying braking torque to the rotor at O Lee <br/> le kneaded rubber granules, during assembly, the viscous granular material As described above, there is nothing that flows out to change the braking torque, so that there is no variation in the braking torque. And since no fluid such as viscous fluid is used to apply braking torque to the rotor,
Viscous fluid does not leak during use to stain the surrounding mechanical parts, and the braking torque does not fluctuate. Further, since there is no need to perform sealing with an O-ring or the like, the number of assembly steps is reduced, and the cost can be reduced.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a sectional view showing a configuration of a rotary damper according to a first embodiment of the present invention. [Figure 2] Ru sectional view showing the structure of a rotary damper according to a second embodiment of the present invention. [EXPLANATION OF SYMBOLS] 1 housing 2 housing body 3 Cap 4 rotor 4f flange 4x shaft portion 11 housing 12 rotor 12f flange portion 12x shaft portion 21 oil compounded rubber granules

──────────────────────────────────────────────────続 き Continuation of front page (72) Inventor Takeshi Kasai 184 Maioka-cho, Totsuka-ku, Yokohama-shi, Kanagawa Prefecture Nifco Co., Ltd. (56) References JP-A-62-270837 (JP, A) JP-A-62- 261727 (JP, A) JP-A-49-12282 (JP, A) JP-A-4-337132 (JP, A) JP-A-4-337133 (JP, A) JP-A-5-54835 (JP, U) (58) Field surveyed (Int. Cl. ⁷ , DB name) F16F 7/06

Claims (1)

(57) [Claim 1] In a rotary damper for applying a braking torque to a rotating portion of a rotor that rotates in an operating chamber formed in a housing, the operating chamber is filled with oil-kneaded rubber particles, A rotating damper, which is in contact with a rotating portion of the rotor.