JP2000046087A - Rotary damper - Google Patents

Abstract

PROBLEM TO BE SOLVED: To generate the high torque even in the case of using a low-viscosity viscous liquid by having a nearly cylindrical sleeve to be arranged between a tip end surface of a partitioning wall of a casing and a peripheral surface of a rotary shaft and provided with an outer diameter at a degree capable of sliding-contact with the tip end surface of the partitioning wall in the peripheral surface thereof. SOLUTION: A sleeve 5 is fitted to the periphery of a rotary shaft 3 by engaging an engaging groove 51 with an engaging projection 33 projected from the peripheral surface of the rotary shaft 3. With the turn of the rotary shaft 3, the peripheral surface is turned while making a contact with a tip surface 21a of a partitioning wall 21 of a easing 2. Since irregularity of the tip surface 21a of the partitioning wall 21 is absorbed by the elastic force, the generation of clearance between the peripheral surface of the rotary shaft 3 and the tip surface 21a of the partitioning wall 21 of the casing 2 is prevented by arranging the sleeve 5 between them. As a result, leakage of the viscous liquid from a slide-contact surface between the rotary shaft 3 and the partitioning wall 21 of the casing 2 is prevented, and the high torque is generated even in the case of using the viscous liquid having a low viscosity.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary damper for delaying the rotation of a rotating lid or a door which is opened and closed by rotating.

[0002]

2. Description of the Related Art Conventionally, as a rotary damper for delaying the rotation operation of a rotating lid or a rotating door which opens and closes by rotating, as shown in FIG. A rotary shaft 130 disposed along the axial center of the rotary shaft 120 and having an outer diameter such that the outer peripheral surface is in sliding contact with the distal end surface 121 a of the partition wall 121 of the casing 120, and protruding from the outer peripheral surface of the rotary shaft 130. And the rotation shaft 1 in the liquid chamber 150 filled with the viscous liquid.
A rotary damper configured to include a vane member 140 that rotates with the rotation of the rotary member 30 is known. This type of rotary damper generates a predetermined torque by compressing a viscous liquid filled in a liquid chamber by a vane member that rotates in accordance with the rotation of a rotation shaft, thereby causing a rotating operation of a rotating lid or the like. Can be delayed.

[0003]

However, in the conventional rotary damper, in consideration of the manufacturing cost, the strength of parts, etc., both the rotating shaft and the vane members, which are constituent members, are made of a metal material, and the die-casting and the lost Many are integrally molded by a casting method such as the wax method,
The one-piece type made by these methods generally has a rough surface roughness, which has caused various problems.
That is, if the surface roughness of the outer peripheral surface of the rotating shaft is rough, a slight gap is generated between the outer peripheral surface of the rotating shaft and the front end surface of the partition wall portion of the casing, and the vane member rotates with the rotation of the rotating shaft. When the viscous liquid rotates and compresses the viscous liquid, the viscous liquid leaks out of the gap, so that it was difficult to generate a high torque especially when a low-viscosity liquid is used. To solve this problem, the surface roughness of the outer peripheral surface of the rotating shaft may be made precise, but since the vane member is projected on the outer peripheral surface of the rotating shaft, grinding cannot be performed, and precision finishing is difficult. Met.

An object of the present invention is to prevent a viscous liquid from leaking from a sliding contact surface between a rotating shaft and a partition of a casing, and to generate a high torque even when a low-viscosity liquid is used. To provide a rotary damper.

[0005]

According to a first aspect of the present invention, there is provided a rotary damper having a bottomed substantially cylindrical shape having a partition wall portion protruding from an inner peripheral surface toward an axial center. A rotating shaft disposed along the axial center of the casing; and a rotating chamber protruding from an outer peripheral surface of the rotating shaft, wherein the rotating chamber is filled with a viscous liquid formed in the casing. A vane member that rotates with the shaft,
A lid member for closing an upper opening of the casing, wherein the rotary damper is disposed between a distal end surface of a partition of the casing and an outer peripheral surface of the rotary shaft, and the outer peripheral surface is formed of the partition. Characterized in that it has a substantially cylindrical sleeve formed to have an outer diameter enough to be in sliding contact with the tip end surface of the sleeve.

According to a second aspect of the present invention, there is provided a rotary damper according to the first aspect, wherein the sleeve is made of a synthetic resin. Claim 3
The rotary damper according to the present invention is the rotary damper according to claim 1 or 2, wherein the vane member has a length substantially equal to an axial length of the vane main body. And a synthetic resin vane cover that is wider in the circumferential direction than the radial end face and covers at least the radial end face. A rotary damper according to a fourth aspect of the present invention is the rotary damper according to any one of the first to third aspects, wherein the viscous liquid passes through a back surface inside the lid member. An exchangeable spacer plate having a path is provided.

[0007]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a transverse sectional view showing a rotary damper 1 according to the present embodiment, and FIG. 2 is a longitudinal sectional view of the rotary damper 1. As shown in these drawings, the rotary damper 1 includes a casing 2, a rotating shaft 3, a vane member 4, a sleeve 5, a lid member 6, and the like.

The casing 2 is formed in a substantially cylindrical shape having a bottom with an upper surface opening, and has an inner peripheral surface 2a on the inner peripheral surface 2a of which a substantially fan-shaped partition wall 21 projecting toward the center of the casing 2 in the axial direction.
Are formed. The distal end surface 21a of the partition 21 located near the axial center of the casing 2 is connected to a sleeve 5 described later.
Are formed in a substantially circular arc shape in plan view so as to be in sliding contact with the outer peripheral surface of. A liquid chamber 22 is formed in the casing 2 with the partition 21 as a boundary, and the liquid chamber 22 is filled with a viscous liquid such as grease. Also, the upper surface opening 2 of the casing 2
A cover member 6 through which the rotating shaft 3 can be inserted is provided at b.

The lid member 6 is substantially disk-shaped, and has a lid body 61 having a rotation shaft insertion hole 61a formed substantially at the center and a disk body having a rotation disk insertion hole 62a formed substantially at the center. It has a guide plate 62. The lid main body 61 and the guide plate 62 are arranged such that the lid main body 61 is disposed on the front side and the guide plate 62 is disposed on the rear side, and the back surface 62b of the guide plate 62 is in contact with the front surface 7a of the spacer plate 7 described below.

The spacer plate 7 is disposed inside the lid member 6 such that the back surface 7b contacts the upper end surface of the partition 21 of the casing 2 and the upper end surface of the vane member 4. As shown in FIG. 3, a liquid flow path 71 formed of a groove formed in an arc shape is provided on the back surface 7 b of the spacer plate 7. By passing through, a predetermined torque can be generated. In addition, as shown in FIG.
Also, if the vane member 4 is formed so as to gradually decrease in the braking force exerting direction, a larger braking force can be exerted as the vane member 4 rotates in the braking force exerting direction. In addition, if a plurality of spacer plates 7 in which the liquid flow paths 71 are formed in various shapes are prepared, the braking characteristics of the rotary damper 1 can be changed in accordance with a change in torque on the movable side of the rotary lid or the like. This can be dealt with only by replacing the spacer plate 7 alone.

In this embodiment, the liquid flow path 71 is provided on the back surface 7b of the spacer plate 7.
Is not provided, the inner surface 2c of the bottom wall of the casing 2
Alternatively, a liquid flow path may be formed on the back surface 62b of the guide plate 62. Further, the lid member 6 is constituted only by the lid main body 61,
When the guide plate 62 is not provided, a liquid flow path may be formed on the back surface 61b of the lid main body 61.

The rotating shaft 3 is formed in a substantially cylindrical shape, and has one end 3.
1 is inserted through rotary shaft insertion holes 61a and 62a formed in a lid main body 61 and a guide plate 62 constituting the lid member 6, and a rotary shaft insertion hole 7c formed substantially in the center of the spacer plate 7.
The other end 32 is fitted in a groove 23 formed substantially at the center of the bottom wall inner surface 2 c of the casing 2, and is disposed along the axial center of the casing 2. As shown in FIGS. 1 and 4, an engaging projection 33 and a vane member 4 described below project from the outer peripheral surface of the rotating shaft 3 at a position facing each other on the rotating shaft 3. Engagement projection 33 and vane member 4
Are formed integrally with the rotating shaft 3.

The vane member 4 protrudes from the outer peripheral surface of the rotating shaft 3 and is disposed so as to be located in the liquid chamber 22.
The vane member 4 according to the present embodiment includes a vane body 41 and a vane cover 42 as shown in FIGS. The vane main body 41 is formed in a substantially rectangular flat plate shape, and has a length along the axial direction.
1a comes into sliding contact with the back surface 7b of the spacer plate 7, and the lower end surface 41b
Has a length enough to slide on the bottom wall inner surface 2 c of the casing 2. The length along the radial direction is the casing 2
Is formed shorter than the distance along the radial direction from the inner peripheral surface 2a to the outer peripheral surface of the rotating shaft 3. Vane cover 42
Is made of synthetic resin, and the length in the axial direction is
While having a thickness substantially equal to or greater than the distance from the radial end face 41c of the vane body 41 to the inner peripheral face 2a of the casing 2, and the radial end face 41c of the vane body 41, The surface 41d of the vane body 41,
41e.

By configuring the vane member 4 in such a configuration, it is possible to prevent a gap from being formed between the vane cover 42 and the inner peripheral surface 2a of the casing 2 due to the elastic force of the vane cover 42, and to realize the vane body 41. In addition, since the entire thickness of the vane member 4 including the vane cover 42 along the circumferential direction increases, the sliding contact surface between the spacer plate 7 and the vane member 4 and between the bottom wall inner surface 2c of the casing 2 and the vane member 4 The leakage of the viscous liquid from the container is extremely reduced. The vane cover 42 may perform such a function, and can cover at least the radial end face 41c of the vane main body 41. The width along the circumferential direction is closer to the radial end face 41c than the width of the vane main body 41. It should just be able to make it wide.

The sleeve 5 is made of a synthetic resin, and is formed in a substantially cylindrical shape as shown in FIGS. 1 and 4, and has a cutout formed in a part of the outer periphery for the vane member 4 to be inserted. . The outer diameter of the sleeve 5 is such that the outer peripheral surface is in sliding contact with the distal end surface 21 a of the partition 21 of the casing 2. On the inner peripheral surface of the sleeve 5, there is formed an engagement groove 51 which is engraved linearly in the axial direction. The sleeve 5 configured as described above is configured such that the engagement groove 51 is
The outer peripheral surface of the casing 2 is engaged with the engaging projection 33 protruding from the outer peripheral surface of the casing 2, and is fitted on the outer periphery of the rotary shaft 3. It rotates while sliding on it. If a sleeve 5 made of synthetic resin is used as in the present embodiment, the processing is easy and the finished surface on the outer periphery can be made precise. In addition, the sleeve 5 is provided between the outer peripheral surface of the rotating shaft 3 and the distal end surface 21a of the partition 21 of the casing 2 in order to absorb unevenness of the distal end 21a of the partition 21 by its elastic force. Thus, it is possible to prevent a gap from being formed between the casing 2 and the front end surface 21a of the partition 21. As a result, the viscous liquid does not leak from the sliding contact surface between the rotary shaft 3 (the sleeve 5 that rotates together with the rotary shaft 3) and the partition 21 of the casing 2, so that even when a low-viscosity viscous liquid is used, High torque can be generated. Since the sleeve 5 has a substantially cylindrical shape, the outer peripheral surface can be ground.
It can also be formed from a metal material.

In the rotary damper 1 configured as described above, one end 31 of the rotating shaft 3 is connected to a shaft (not shown) such as a rotating lid to be braked, and the rotary damper 1 is arranged at a predetermined position. Used for installation. When the rotating lid or the like performs the closing operation, the shaft body of the rotating lid or the like, the rotating shaft 3 and the vane member 4 connected thereto rotate in one direction with the closing operation. At this time, the vane member 4 rotates while compressing the viscous liquid, but the viscous liquid slides on the sliding surface between the sleeve 5 rotating with the rotary shaft 3 and the partition 21 of the casing 2, and the vane member 4 and the casing 2 Move through only the liquid flow path 71 provided in the spacer plate 7 without leaking from any of the sliding surfaces with the inner peripheral surface 2a. Accordingly, the rotary damper 1 generates a predetermined torque by viscous resistance generated at that time, slowly rotates a shaft body such as a rotary lid connected to the rotary shaft 3, and delays the rotation operation of the rotary lid and the like. Move. Depending on factors such as the weight of the rotating lid or the like to be braked, the braking force of the rotary damper 1 may be too large, or the braking force may be significantly changed, or it may be desired to change the position at which the braking force starts to increase. . In such a case, it is possible to cope by removing the lid member 6 and replacing the spacer plate 7 with another spacer plate.

[0017]

According to the rotary damper of the present invention, since the sleeve is provided between the outer peripheral surface of the rotary shaft and the front end surface of the partition wall of the casing, the surface roughness of the outer peripheral surface of the rotary shaft is reduced. Even in a rough case, the sleeve can prevent a gap from being formed between the sleeve and the front end surface of the partition wall. As a result, there is no leakage of the viscous liquid and high torque can be generated even when a low-viscosity viscous liquid is used. Further, by using a member having a vane cover made of synthetic resin as the vane member, it is possible to prevent leakage of viscous liquid from a sliding contact surface between the vane member and the inner peripheral surface of the casing,
The sealing performance can be further improved. Further, when it is desired to change the braking force, it is possible to cope by replacing the spacer plate with another spacer plate having a liquid flow path formed in various shapes.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a rotary damper according to one embodiment of the present invention.

FIG. 2 is a longitudinal sectional view showing the rotary damper according to the embodiment.

FIG. 3 is a bottom view showing a spacer plate used in the embodiment.

FIG. 4 is a perspective view showing a structure of a rotary shaft, a vane member, and a sleeve used in the embodiment.

FIG. 5 is a cross-sectional view showing a conventional rotary damper.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Rotary damper 2 Casing 21 Partition part 3 Rotating body 4 Vane member 41 Vane main body 42 Vane cover 5 Sleeve 6 Lid member 61 Lid main body 62 Guide plate 7 Spacer plate 71 Liquid flow path

Claims (4)

[Claims] 1. A substantially cylindrical casing with a bottom provided with a partition protruding from an inner peripheral surface toward an axial center, a rotating shaft disposed along an axial center of the casing, and the rotation. A vane member protruding from an outer peripheral surface of a shaft and rotating together with the rotating shaft in a liquid chamber filled with a viscous liquid formed in the casing; and a lid member closing a top opening of the casing. In the rotary damper having, disposed between the distal end surface of the partition wall portion of the casing and the outer peripheral surface of the rotating shaft, the outer peripheral surface has an outer diameter that is in sliding contact with the distal end surface of the partition wall portion. A rotary damper having a substantially cylindrical sleeve formed. 2. The rotary damper according to claim 1, wherein said sleeve is made of a synthetic resin. 3. The rotary damper according to claim 1, wherein said vane member has a length substantially equal to an axial length of said vane main body, and a radial end face of said vane main body. Wider along the circumferential direction than
And a synthetic resin vane cover for covering at least the radial end face. 4. The replaceable spacer according to claim 1, wherein the rotary member has an arc-shaped liquid passage inside the cover member, the back surface through which the viscous liquid passes. A rotary damper comprising a plate.