JPS63167136A - Rotary damper - Google Patents

Abstract

PURPOSE:To provide friction resistance between a rotor and a seal member to a fixed value, by providing an elastic seal member which holds its peripheral edge to be liquid-tightly fixed to the internal wall of a casing placing one part of the inner to be brought into liquid-tight contact with the rotor. CONSTITUTION:A disc-shaped elastic seal member 4 is provided to be arranged between a cap 3 and the upper surface of a rotor 2, and a peripheral edge 41 of the elastic seal member 4 is liquid-tightly fixed to the internal wall of a casing 3. While this seal member 4 provides its inner upper and bottom surfaces to be arranged so that these surfaces are slightly separated from the bottom surface of the cap 3 and the upper surface 22 of the rotor 2, and in this space, free bending deformation by elasticity can be performed. Contact friction force, acting on a line contact part, is only by slight force by bending elasticity in the seal member 4, and sliding friction force is prevented from excessively large increasing to a design value or more.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention provides a rotary damper for alleviating impact force by smoothly braking the rotational force and speed of various devices using liquid resistance. Regarding.

<Conventional Examples and Problems> In this type of rotary damper, as shown in Fig. 3, a rotor (2)' rotating within a casing (1) is used for liquid resistance and sealing of a sealing liquid such as grease (G). Braking torque is generated by receiving fffi resistance with the 0 ring (3)°.

In the figure, (21)' is the rotor axis, and (4)° is the rotor axis (2
1) It is a cap that closes the casing opening while supporting '.

In this structure, the O-ring (3)' is arranged so as to be sandwiched between the inner circumferential wall (31)' of the casing and the outer circumferential surface (22)' of the rotor. Therefore, in order to improve the sealing performance, it is necessary to strengthen the clamping pressure, but as a result, the compressive deformation in the 0 ring (3)° increases, and the sliding friction with the rotor (2)', that is, the braking torque increases. Too much. Therefore, if the torque acting on the rotor @(21)' is small, it may not be possible to exert a damping effect.

In addition, in order to make a small damper that passes external force with a particularly small rotational torque, the design dimensions should be 1/100 m+
It is necessary to have an accuracy of n 41st place. However, since the casing (1) is usually molded from a plastic material, it contracts slightly in the diametrical direction of the rotor due to heating during molding.Moreover, this shrinkage varies depending on the material, heating conditions, etc. Therefore, it is impossible to maintain uniform dimensions even if the design takes into account the dimensions after shrinkage. Therefore, if the O-link (3) is installed in this condition, the amount of pressure deformation will be large and the rotor (2) The frictional resistance with the circumferential surface of the engine was greater than the designed value, leading to galling at startup, that is, the generation of excessive braking torque at startup, leading to malfunctions and malfunctions.

<Means for Solving the Problems> The present invention was proposed in order to eliminate the above-mentioned drawbacks, and its purpose is to completely maintain the liquid sealing action while reducing fine accumulations during casing molding. To the degree error, t! It is an object of the present invention to provide a rotary damper that can maintain ffaJf and resistance between a rotor and a sealing member at - constant without being affected.

Another object of the present invention is to provide a rotary damper suitable for damping an external force that originally has a small rotational torque.

The above object of the present invention is to provide a rotary damper in which a rotor rotating within a casing is provided to receive liquid resistance; a rotor shaft protruding in the direction; a cap for closing the opening of the casing;
The cap is disposed between the cap and the rotor disk surface, and its outer peripheral edge is liquid-tightly clamped and fixed to the inner wall of the casing, and the inner part of the cap is not subjected to external force against the rotor disk surface and/or the rotor shaft circumferential surface. Only by mutual contact force? 1! This is achieved by a rotary damper consisting of a disk-shaped elastic seal member that is brought into close contact with the rotary damper.

<Example> Next, the present invention will be explained in more detail according to an example shown in FIG. 1.2.

(1) is a casing having a shallow circular recess, and a bearing protrusion (11) is connected to the center of the bottom of the casing. (15
) is a locking edge rib formed at the opening of the circular recess. (2) is a disk-shaped rotor, which is arranged in the casing (1) with a slight gap between the bottom surface (12) and the inner peripheral surface (13) of the circular recess, and the bearing protrusion (
11). This gap is then filled with a liquid (G) having a high viscous resistance, such as grease. A rotor shaft (21) protruding outward from the opening of the casing is connected and fixed to the center of the upper surface of the rotor (2), and a ridge (23) is provided on the upper surface (22) of the rotor (2).
! ! It is shaped like an end ring. Also, the rotor (2)
An endless ring-shaped concave groove (24) is formed on the lower surface of the holder.

(14) is the bottom surface (12) of the casing corresponding to the groove.
) is a ring-shaped protrusion.

The uneven structure according to (24) and (14) is the rotor (2).
It is formed as necessary to increase the contact surface between the surface and the liquid (G), and an embodiment that does not have a concavo-convex structure as shown in FIG. 3 is also included in the present invention.

(3) is a plate-shaped cap for closing the opening of the casing, and in the center thereof is an insertion hole (3) for the rotor shaft.
1) exists.

(4) is a disk-shaped elastic sealing member, for example, a hard rubber sealing member, disposed between the cap (3) and the upper surface of the rotor (2), and the cap (3) is attached to the edge of the rotor. The outer peripheral edge (41) is liquid-tightly fixed to the inner wall of the casing by the clamping force when the lip (15) is press-fitted and locked from the outside in a snap-in manner. On the other hand, the seal member (4
) are arranged so as to be slightly spaced apart from the lower surface of the cap (3) and the upper surface of the rotor (22), allowing free bending deformation due to elasticity within that space. There is.

Thus, the lower surface of the seal member (4) comes into line contact with the upper surface ridge (23) of the rotor (2), and the inner peripheral edge (42) of the solid shaft hole contacts the outer peripheral surface of the rotor shaft (21). Line contact to seal the filling liquid. At this time, the contact frictional force acting on the line contact portion is only a slight force due to the bending elasticity of the sealing member (4), and no pressure or pressing force from other members acts on the sealing member (4). The sliding friction force does not exceed the design value. Furthermore, even if the casing material undergoes thermal contraction during molding, the shrinkage error will not cause compressive deformation of the sealing material at the line contact area, so abnormal braking torque to the rotor (2) will not occur. It's something that doesn't exist.

Although the drawings show a case where the sealing member (2) contacts both the rotor (2) and the rotor shaft (21) to perform liquid sealing, it may also contact only one of them.

Further, although the drawing shows a case where the ridge (23) is formed on the upper surface of the rotor (2), it is also possible to form a ring-shaped ridge on the lower surface of the seal member (4). Of course.

Effects> According to the rotary damper according to the present invention, each of the objectives described above can be well achieved, and since it has a simple structure,
It is easy to assemble, and can be mass-produced at low cost.
It has many useful properties.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an embodiment of a rotary damper according to the present invention, FIG. 2 is a plan view thereof, and FIG. 3 is a sectional view showing a conventional rotary damper. (1) --- Casing, (2) ----1 Rotor, (3) --- Cap, (4) --- Seal member,

Claims (1)

[Scope of Claims] 1. A rotary damper provided so that a rotor rotating within a casing receives liquid resistance, comprising: a disc-shaped rotor rotatably disposed within a bottomed casing; and a portion outside an opening of the casing. a rotor shaft protruding toward the casing; a cap for closing the opening of the casing; and a cap disposed between the cap and the rotor disk surface, the outer periphery of which is fluid-tightly clamped and fixed to the inner wall of the casing; A rotary damper comprising: a disk-shaped elastic seal member, the inner part of which is brought into liquid-tight contact with a rotor disk surface and/or a rotor shaft circumferential surface only by mutual contact force without receiving any external force; 2. The sealing member is formed in a donut shape, and the inner peripheral edge thereof is in line contact with the circumferential surface of the rotor shaft, and a part of the lower surface thereof is provided in line contact with the rotor disk surface. Rotary damper described in 1A.