JPH10141411A - Rotary damper - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fixing method which does not require the positioning of a separate block part of a packing case and a casing first and provide a structure in which additional tightening can be simplified by preventing coming off force generated by internal pressure of a rotary damper from being applied to an additional tightening part of the packing case second. SOLUTION: A casing 1 having a bottom in which a vane body 6 connected with a shaft 101 is stored, a bearing 108 which seals a vane body storage part of the casing 1 having the bottom and on which a seal 115 is mounted on an outer peripheral end face, and a lower cap 104 which comes into contact with the bearing as if it covers the bearing are fitted and inserted into an inner face 103C of a cylindrical part of a packing case 103A in which an oil seal 116 is provided in a bottom part thereof sequentially to connect them with an outer peripheral side face of the lower cap by tightening an end face of the packing case 103A additionally. The inner face 103C of the cylindrical part of the packing case 103A and outer faces of the casing 1 having the bottom and the bearing 108 are fixed firmly by using adhesive.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a hydraulic rotary damper which attenuates a vehicle or other external vibrations by using a swinging motion.

[0002]

2. Description of the Related Art As a conventional rotary damper of this type, the present applicant has filed Japanese Patent Application No. 8-150305. The structure of the rotary damper will be described based on the embodiment shown in FIG. The shaft 101 has a hollow inside, and a free piston 105 having a seal 105A mounted on its outer surface is movably housed in the hollow, and a tank chamber 104A including a right end hollow portion 101B of the shaft and a gas at a predetermined pressure are provided. Are enclosed to define a gas chamber 101A for pressurizing the tank chamber 104A to a predetermined pressure. The vane body 106 has two vanes 106A and 106B, and is fixed to the shaft 101 by mechanical coupling such as spline coupling.

[0003] A pair of left and right bearings 107 and 108 for holding the casing 102 rotatably hold the vanes 106A and 106B accommodated in the casing 102, and a shaft 101 connected to the vane body 106 at the center thereof. It has a bearing function to rotatably support it and a function as a thrust bush for receiving a thrust input of the shaft 101, and is formed to be thick so as to withstand the high pressure of the oil chambers A, B, C and D. . The bearings 107 and 1 slidingly contact the cylindrical portion 106C of the vane body.
As shown in the enlarged view of FIG. 3 (B), projecting portions 107A and 108A of minute steps d are provided on the vane side 08 so that the side surfaces of the vanes 106A and 106B do not slide directly on the bearing end surfaces during thrust input. ing. Projection 107A,
The outer diameter of 108A is set slightly smaller than the outer diameter of the cylindrical portion 106C of the vane body so as not to interfere with the inner diameters of the separate blocks 102A and 102B of the casing 102.

[0004] Cartridge type check valve 109, 1
10, 111 and 112 are press-fitted and fixed to the vanes 106A and 106B, respectively, in the manner shown in the drawing, and the tank chamber 104A
Hydraulic oil is supplied to the oil chambers A, B, C, and D, which are at a negative pressure, from the vane passages 106D and 106E communicating with the oil passages. Also, the vanes 106A and 106B are provided with orifices 106F and 106G for setting the expansion / compression damping force ratio in parallel with the check valves 109 and 112. Casing 1
02, a pair of separate blocks 102A, 102
B is formed, and concentricity with a pair of left and right bearings 107 and 108 is secured by positioning pins 113 and 114 rising from the separate block.

[0005] The packing case assembly 103 includes:
Left bearing 107, casing 102, seal 1
In addition to inserting and supporting the right bearing 108 and the lower cap 104 on which the bearing 15 is mounted, an oil seal 116 that seals the shaft 101 so as not to leak hydraulic oil to the outside is incorporated into the left bottom. ing. The lower cap 104 supports the bearing 108 from the side, seals the working oil via a seal 115 so as not to leak the operating oil to the outside, and forms an oil tank chamber 104A at the center. A hole 104B for injecting hydraulic oil is provided at the bottom of the right end of the lower cap 104, and after injecting hydraulic oil,
It is sealed by a sealing means such as a steel ball 116.

[0006] The packing case assembly 103
Are the body mounting member 103B and the packing case 103A.
And the vehicle body mounting member 103B is fixed to the packing case 103A by projection welding or the like, so that the packing case 103A can be manufactured by press molding suitable for mass production, like the lower cap 104. At the same time, the thickness can be reduced because high pressure is not applied. The packing case 103A is formed by bending the end of the packing case 103A inward (caulking portion Z) so that the pair of bearings 107,
108, the casing 102, and the lower cap 104 are integrally fixed.

[0007] In the method of fixing the packing case 103A and the casing 102, if the required damping torque is smaller than the coupling torque obtained by press fitting, press fitting is sufficient. When the damping torque is larger than the holding torque obtained by press-fitting, laser welding for partially melting and integrating the packing case 103 and the outer peripheral surfaces of the hardly deformable separate block portions 102A, 102B, separate block portions 102A, 102B. Is drilled in advance on the packing case 103 side corresponding to the outer peripheral surface of the seal case, plug welding for integrally welding the perforated portion, a current flows between the packing case 103 and the outer peripheral surfaces of the separate block portions 102A and 102B, It is reinforced by projection welding or the like that partially fuses and integrates using electrical resistance.

Next, the operation of the rotary damper will be described. A vane body 106 is rotatably housed in the casing 102 coaxially with the casing 102.
Are integrally formed with two vanes 106A and 106B at an interval of 180 °. Bearings 107 and 108 are provided on both sides of the casing 102,
Both side surfaces of the cylindrical portion 106C of the vane body 106 are in sliding contact with the projecting portions 107A and 108A of the minute step of the bearing, and the cylindrical portion 106C is in sliding contact with the inner peripheral surfaces of the separate block portions 102A and 102B of the casing 102.

The vanes 106A and 106B are housed inside the casing inner surfaces 102C and 102D and between the separate blocks 102A and 102B, while the separate blocks 102A and 102B and the vane 106
A and 106B define four oil chambers A, B, C and D in the casing 102 filled with high-viscosity hydraulic oil. In this case, the casing 102 is made of an iron-based sintered alloy or a casting material, and the vane body 106 is made of aluminum in order to have a damping force temperature compensation structure that can automatically adjust the generated damping force to almost constant according to the temperature change. By using a material, the clearance can be adjusted using the difference in the coefficient of thermal expansion.

The shaft 10 of the rotary damper is externally provided.
1, the vanes 106A and 106B of the vane body 106 mechanically coupled to the shaft 101 swing in the casing 102, and the oil chambers A and D and B and C alternately expand or contract. Scaled down. At this time, the hydraulic oil in the oil chamber on the side of contraction fits into the fitting gap between the vanes 106A, 106B and the casing inner surfaces 102C, 102D and the vane 10
6A and 106B and the gap between the bearings 107 and 108, the fitting gap between the cylindrical portion 106C of the vane body and the inner peripheral surfaces of the separate blocks 102A and 102B, and the passage 106 in the vane from the orifices 106F and 106G.
D and 106E are pushed out through the check valves 110 and 111 to the expanding oil chamber side, and a required damping force is generated by the flow resistance of the hydraulic oil passing through these minute gaps.

On the other hand, the hydraulic oil leaking from the contracting oil chamber to the shaft side is returned to the tank chamber 104A while being reduced in pressure while passing through the fitting gap between the bearing 108 and the shaft 101 and the oil groove 108B. For this reason, the tank chamber 104A does not become high pressure.
04 can be formed with a thin press material. The hydraulic oil that has flowed back to the tank chamber 104A
Are urged by the pressure of the gas chamber 101A,
The oil is expanded through the oil groove 108B, the passages 106D, 106E in the vane, and the check valves 109, 110, 111, 112 to replenish the oil chamber, thereby preventing cavitation.

[0012]

In Japanese Patent Application No. 8-150305 described in the prior art, as a method of fixing the packing case 103A and the casing 102, a required damping torque is obtained by press-fitting both. When the torque is larger than the torque, the packing case 103A and the outer peripheral surfaces of the separate block portions 102A and 102B that are not easily thermally deformed are partially welded by laser welding. 10
Reinforcement welding such as plug welding in which the outer surfaces of the two are integrally welded, and projection welding in which an electric current is applied between the packing case 103A and the casing 102 to partially melt and integrate them using electric resistance. .

The above-described reinforcing welding is performed on the bearings 107, 1
This is performed after press-fitting the packing 102 into the packing case 103A in a state in which the casing 102 in which components such as the vane body 106 and the like are mounted during the sub-assembly by the positioning pins 113 and 114. In this case, a disc-shaped bearing 108
Conceals the casing 102, so that a marking, such as an identification punch, is required on the outer surface of the packing case corresponding to the separate block portions 102A, 102B that are not easily thermally deformed.

However, since the press-fitting and the reinforcement welding are performed in separate steps, the separate block portions 102A, 10B are difficult to thermally deform the reinforcement welding due to an error in the marking position.
2B, the vanes 106A, 10A
The inner surfaces 102C and 102D of the casing slidingly contacting 6B are thermally deformed by welding, so that so-called serrations which hinder the rotation of the vane body 106 are generated. In FIG. 3 (C), part of the hydraulic oil in the oil chambers A and D, which is reduced by the right turn of the vane body, passes through the orifices 106F and 106G, passes through the vane passages 106D and 106E, and passes through the check valve 11.
The check valves 110 and 111 are to be supplied to the expanding oil chambers B and C via the first and second orifices 106F and 106G.
The hydraulic oil passing through the orifice is disposed on the outer side of the return passage 108B connected to the tank chamber 104A with respect to the tank room 104A via the in-vane passage 106D and the return passage 108B.
And the supply to the oil chambers B and C via the check valves 110 and 111 was insufficient.

The present invention has been made in view of the above-described circumstances, and has as its object the first purpose is to fix the packing case 103A and the separate block portions 102A and 102B of the casing 102 without positioning. Secondly, to provide a structure capable of simplifying the tightening by preventing the pull-out force generated by the internal pressure of the rotary damper from being applied to the tightenable portion of the packing case, and thirdly, to reduce the size. It is an object of the present invention to provide a structure capable of efficiently replenishing an expanding oil chamber with hydraulic oil flowing out from an oil chamber through an orifice. (Continuation of Description R21-2058A)

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the structure of a rotary damper according to the present invention will be described based on a first embodiment of the present invention shown in FIG. The same parts as in the prior art will be described using the same part numbers, and only different parts will be given different part numbers. As for the operation and the effect, only the portions different from the conventional technology will be described.

The feature of the first embodiment of the present invention shown in FIG. 1 is that the bearing 107 having the conventional structure shown in FIG.
That is, the bottomed casing 1 is formed on the body. At the time of assembling, first, the vane body 6 previously connected to the shaft 101 by a spline or the like is housed in the bottomed casing 1. Then the adhesive to the packing case 103A coated in L ₂ section of the outer tubular portion inner surface 103C, interpolating fitting the bottomed casing 1 accommodating the vane body 6. After an adhesive is applied further to L ₁ interval of the packing case inner surface,
The bearing 108, which is aligned with the positioning pin 114 to ensure concentricity, is inserted.

Thereafter, a seal 115 is attached to the outer peripheral chamfered portion on the right end face of the bearing, and a lower cap 104 is closely fitted and inserted into the right end face of the bearing.
By bending the end of A inward (same as the tightenable portion Z in FIG. 3), the bottomed casing 1, the bearing 108, and the lower cap 104 are integrally fixed. Of course, the adhesive to the packing case 103A coated in L ₁ + L ₂ section of the outer tubular portion inner surface 103C, and a bottomed casing 1 accommodating the vane member 6 which is coupled in advance by splines to the shaft 101, the bottom Bearing 108 aligned with locating pin 114 on cylindrical casing 1
Can be fitted as a sub-assembly in which the sub-assembly is connected. In this case, a starfish-shaped relief groove is formed in the outer diameter portion of the bottomed casing 1 at several places, or the outer diameter of the bottomed casing 1 is made slightly smaller than the outer diameter of the bearing 108. By doing so, it is possible to prevent the adhesive from being scraped off by the bottomed casing 1 and the bearing 108 from being insufficiently bonded.

In the rotary damper assembled as described above, the packing case 103A, the bottomed casing 1 and the bearing 108 are fixed with an adhesive. The fixing strength of the bearing 108 in the axial direction by the adhesive is F ₁ ,
The fixing strength in the axial direction of the bottomed casing 1 is F ₂ , the fixing strength in the rotating direction of the bearing 108 is T ₁ , the fixing strength in the rotating direction of the bottomed casing 1 is T ₂ , and the breaking stress of the fixed adhesive is Is τ ₁ , the breaking stress of the packing case material is τ ₂ , and the inner diameter of the packing case is D, the following relationship is established. _{F 1 = π · D · L} 1 · τ 1 F 2 = π · D · L 2 · τ 1 T 1 = π · D 2 · L 1 · τ 1/2 T 2 = π · D 2 · L 2 · comparing tau _1/2 expression and expression from the shape shown in FIG. ₁ L 1 <L ₂
(That is, F ₁ <F ₂ ), the fixing strength F ₁ calculated by the equation satisfies the following equation with respect to the axial thrust Fр received by the bearing due to the internal pressure of the rotary damper, with the safety factor being k _1. Thus, D and L ₁ may be determined. F ₁ ≧ Fр · k ₁

Next, the adhesive strength in the rotational direction of the adhesive with respect to the maximum damping torque Tm generated by the rotation of the vane body 106 will be considered. The bearing 108 includes the vane body 6
Receives the rotational friction torque of the inner peripheral contact surface due to the rotation of, but does not directly apply the damping torque. Since the rotational friction torque is relatively small, the fixation strength in the rotational direction according to the formula may hardly matter. However, the maximum damping torque Tm acts on the bottomed casing 1 as a reaction force. Since this value is large, D and L ₂ may be determined such that the safety factor k ₂ with respect to the maximum damping torque Tm is satisfied by the fixing strength T ₂ in the rotation direction calculated by the equation, and the following equation is satisfied. T ₂ ≧ Tm · k ₂

Since the internal pressure of the rotary damper is applied to the contact surface between the bottomed casing 1 and the bearing 108, a portion corresponding to the contact surface of the packing case 103A is
Axial thrust Fp based on the internal pressure of the rotary damper
Acts in the direction of extending the packing case. Therefore, if the thickness of the packing case 103A is t, the breaking stress is τ ₂ , and the safety factor is k ₃ , the breaking strength of the packing case is F
A plate thickness t that satisfies the following expression may be adopted as ₁ (≒ the strength of the adhesive in the axial direction). F ₁ = π · D · t · τ ₂ ≒ π · D · L ₁ · τ ₁ ≧ Fp · k ₃

That is, by fixing the outer peripheral sides of the bottomed casing 1 and the bearing 108 to the inner surface of the outer cylindrical portion of the packing case 103A with an adhesive, the thrust in the axial direction of the rotary damper is applied to the tightenable portion Z of the packing case. Will not be added. Therefore, the tightenable portion Z is located in the oil tank chamber 104A.
It only has to withstand the low internal pressure. Since the tightening strength in this case may be relatively small, the plate thickness t according to the formula can be reduced, so that a simple tightenable structure can be achieved and the weight can be reduced.

Next, the material of each component will be described. The packing case 103A and the lower cap 104 are formed from a thin-walled pressed steel plate or the like because high pressure is not applied thereto. The bottomed casing 1 and the bearing 108 are molded from a material having good slidability, such as an iron-based sintered alloy or a casting, and the shaft 101 is directly rotatably supported. The parts related to the caulking have a planar matching structure, so that it is easy to secure an appropriate gap between the bottomed casing 1 and the bearing 108 and the vanes 6A and 6B, and the caulking becomes easy.

In FIG. 1 (B), when the vanes 6A, 6B turn right, the oil chambers A, D contract, so that one of the hydraulic oil
The part passes through the orifice 6F, 6G, the passage 6D in the vane,
It is exhaled in 6E. However, when the outlets of the orifices 6F, 6G to the passages 6D, 6E in the vane are viewed from the return passage 108B to the tank chamber 104A, the check valves 110, 1
Since it is arranged on the outer circumferential side than 11, the hydraulic oil discharged from the orifice flows smoothly to the check valves 110 and 111 having a short passage and a small passage resistance,
Since the expanding oil chambers B and C can be efficiently replenished, cavitation caused by insufficient replenishment of hydraulic oil can be prevented.

A pair of the bottomed casing 1 and the bearing 108 for holding the vane 6 sandwich the vanes 6A and 6B at the center thereof so as to be rotatable.
The bearing has a function of rotatably supporting the shaft 101 coupled to the shaft 101, a function as a thrust bush for receiving a thrust input of the shaft 101, and the oil chambers A,
It is formed thick to withstand the high pressure of B, C and D. It should be noted that the bottomed casing 1 and the bearing 108 which are in sliding contact with the cylindrical portion 6C of the vane body are provided on the vane side of FIG.
As shown in (A), when the thrust is input, the vanes 6A, 6B
Projecting part 1 of the small step d so that the side surface of
C, 108A. The outer diameter of the protrusions 1C and 108A is set slightly smaller than the outer diameter of the cylindrical portion 6C of the vane body, and the separate blocks 1A and 1A of the bottomed casing 1 are formed.
It does not interfere with the inner diameter of B.

Next, the operation of the rotary damper will be described. A vane body 6 is rotatably housed in the bottomed casing 1 concentrically with the bottomed casing 1, and the vane body 6 has two vanes 6.
A and 6B are integrally formed with an interval of 180 °. On the right side of the bottomed casing 1, a bearing 108 is provided.
Are provided, and both side surfaces of the cylindrical portion 6C of the vane body 6 are in sliding contact with the projecting portions 1C and 108A of the minute step of the bearing, and the cylindrical portion 6C is inside the separate block portions 1A and 1B of the bottomed casing 1. It is in sliding contact with the peripheral surface.

The vanes 6A and 6B are provided on the inner surface 1D of the casing.
1E, while being housed between the separate blocks 1A and 1B and between the separate blocks 1A and 1B.
B and the vane 6A, 6B, the bottomed casing 1
Oil chambers A, B, C, filled with high-viscosity hydraulic oil
D is partitioned. In this case, the bottomed casing 1 is made of an iron-based sintered alloy or a casting material so as to have a damping force temperature compensation structure capable of automatically adjusting the generated damping force to almost constant according to the temperature change. 6 is made of an aluminum material, so that the above-mentioned clearance can be adjusted using the difference in the coefficient of thermal expansion.

From outside, the shaft 10 of the rotary damper
When the swinging motion is transmitted to the shaft 1, the vanes 6A and 6B of the vane body 6 mechanically connected to the shaft 101 swing in the bottomed casing 1, and the oil chambers A and D alternate with B and C. Scaled up or down. At this time, the hydraulic oil in the oil chamber on the contracting side is filled with the clearance between the vanes 6A, 6B and the inner surfaces 1C, 1D of the casing and the side surfaces of the vanes 6A, 6B and the bearing 10.
8, the fitting gap between the cylindrical portion 6C of the vane body and the inner peripheral surfaces of the separate blocks 1A and 1B, and the check valves 110 and 111 from the orifices 6F and 6G via the passages 6D and 6E in the vane. The hydraulic fluid is pushed out to the expanding oil chamber side and generates a required damping force by the flow resistance of the hydraulic oil passing through these minute gaps.

On the other hand, the hydraulic oil leaked from the shrinking oil chamber to the shaft side is returned to the tank chamber 104A while being reduced in pressure while passing through the fitting gap between the bearing 108 and the shaft 101 and the return passage 108B. For this reason, since the tank chamber 104A does not have a high pressure, the lower cap 104 can be formed by a thin press material.

A second embodiment of the present invention shown in FIG.
In this embodiment, the positions of the bearing 108 and the bottomed casing 1 are replaced with each other. Since the bonding width L1 of the bottomed casing 1 with respect to the packing case 103A is large, the _first direction is determined by the following formula.
It is much larger than the embodiment. Therefore, the fixed portion is sheared by the axial thrust Fp due to the internal pressure of the rotary damper, and there is almost no concern that the thrust Fp is applied to the tightenable portion.

[0031] There also concerns mentioned above is eliminated, the adhesive packing case 103A coated in L ₁ + L ₂ section of the outer tubular portion inner surface 103C of the packing case, the shaft 1
01 and the bearing 108 with the bottomed casing 1 containing the vane body 6 previously joined by a spline or the like.
It can be inserted as a sub-assembly that is aligned and connected by the positioning pin 114. In this case, by devising the outer diameter of the bearing 108 to be slightly smaller than the outer diameter of the bottomed casing 1, the adhesive is scraped off by the bearing 108 and the adhesion of the bottomed casing 1 is insufficient. To prevent

When the seal 115 is mounted with the adhesive adhered to the inner surface of the outer cylindrical portion of the packing case 103A,
Although the sealing performance is feared to be reduced, since the case of the present embodiment has a sufficient margin for bonding width L ₂ of the bottomed casing 1 for thrust Fp axial due to internal pressure of the rotary damper, the adhesive width by shortening the L ₂ until to miss mounting portion of the seal 115, it is possible to eliminate this concern.

In the case of this embodiment, the bearing 108
Thrust Fp due to the internal pressure of the rotary damper applied to the shaft
Is received on the bottom surface of the packing case 103A, and the bearing 108 receives a relatively small rotational friction torque of the inner peripheral side contact surface due to the rotation of the vane body 6, but the damping torque is not directly applied, Since the positioning pin can withstand the rotational friction torque, the application of the adhesive to the bearing 108 can be omitted.

[0034]

According to the first and second embodiments of the present invention,
Since the outer periphery of the bottomed casing 1 is fixed to the inner surface of the outer cylindrical portion of the packing case with an adhesive, the tightenable portion Z of the packing case only needs to withstand the low internal pressure of the tank chamber 104A, and the tightening strength is relatively high. Since it can be small, a simple tightenable structure can be achieved and the weight can be reduced. In particular, in the second embodiment, the bottomed casing 1 against the axial thrust Fp due to the internal pressure of the rotary damper is used.
Since the bonding width L ₂ of there is enough room, bonding the width L ₂ by shortening until to miss mounting portion of the seal 115, automated step of applying adhesive to the outer tube inner surface of the packing case 103A can do. The first,
In any of the second embodiments, the bottomed casing 1
Alternatively, since the bearing 108 is fixed to the packing case 103A with an adhesive that can be applied at normal temperature, there is no need to consider thermal deformation due to welding as described in the related art. For this reason, even when the adhesive is partially applied to a part of the outer periphery, the application part does not need to be limited to the separate block part, and may be any part of the outer periphery. Is easy. The outlets of the orifices 6F and 6G on the oil chamber side to be further reduced to the passages 6D and 6E in the vane are farther from the recirculation passage 108B to the tank than the check valve for supplying the operating oil to the expanding oil chamber side. Since it is arranged on the outer peripheral side, replenishment of hydraulic oil is facilitated, and occurrence of cavitation can be prevented.

[Brief description of the drawings]

FIG. 1A is a cross-sectional view of a rotary damper according to a first embodiment of the present invention, taken along line XOX. (B) First and second
It is a cross section of a vane part concerning an embodiment.

FIG. 2 is a sectional view taken along line XOX of a rotary damper according to a second embodiment of the present invention.

FIG. 3A illustrates a rotary damper A- according to the related art.
FIG. 3 is a sectional view taken along line A. (B) It is a cross-sectional view of the vane part which concerns on a prior art.

[Explanation of symbols]

 A, B, C, D Oil chamber 1C, 108A Projection of minute step 1 Bottomed casing 1A, 1B Separate block 6 Vane body 6A, 6B vane 6D, 6E Vane passage 6F, 6G Orifice 101 Shaft 103A Packing case 104 Lower cap 104A Tank chamber 108 Bearing 109, 110, 111, 112 Check valve 115 Seal 116 Oil seal

Claims (6)

[Claims] A casing and a bearing constituting a pressure-resistant wall are inserted into a packing case formed in a cylindrical shape with a bottom and accommodating a vane body coupled to a shaft, and the casing and the bearing are fitted at the center of the pair of casings and the bearing. A rotatable shaft, to which the vane body is connected, is inserted rotatably, the inside is sealed by an oil seal interposed at the bottom of the packing case, and extends from the shaft side with a separate block provided on the inner peripheral surface of the casing. In a main body structure of a rotary damper in which a casing is partitioned into a plurality of oil chambers with a vane, a bottomed bottom housing a vane body coupled to a shaft on an inner surface of an outer cylindrical portion of a packing case with an oil seal interposed at a bottom portion. And a seal that seals the vane body accommodating portion of the bottomed casing and attaches a seal to the outer peripheral end face. A rotary damper, wherein an annular ring and a lower cap that comes into contact with the bearing so as to cover the bearing are sequentially inserted and joined to the outer peripheral side surface of the lower cap by caulking an end surface of the packing case. 2. The bottomed casing and bearing are machined after being formed from a sintered alloy or a casting, etc., whose slidability is guaranteed, and have both a bearing function and a pressure resistance function. 2. The rotary damper according to claim 1, wherein a protrusion having a minute step is provided on the vane body side of the bottomed casing and the bearing in sliding contact with the vane side surface to ensure an appropriate clearance. 3. The rotary damper according to claim 1, wherein the inner surface of the outer cylindrical portion of the packing case and the outer surfaces of the bottomed casing and the bearing are fixed with an adhesive. 4. A casing and a bearing constituting a pressure-resistant wall are inserted into a packing case formed in a cylindrical shape with a bottom so as to accommodate a vane body coupled to a shaft, and the casing and the bearing are fitted at the center of the pair of casings and the bearing. A rotatable shaft, to which the vane body is connected, is inserted rotatably, the inside is sealed by an oil seal interposed at the bottom of the packing case, and extends from the shaft side with a separate block provided on the inner peripheral surface of the casing. In the main body structure of the rotary damper in which the casing is partitioned into a plurality of oil chambers with the vane, the vane body accommodating portion of the bottomed casing is sealed on the inner surface of the outer cylinder portion of the packing case with an oil seal interposed at the bottom. Bearing and a bottomed case housing the vane body connected to the shaft and fitted with a seal on the outer peripheral end face. A rotary damper, wherein a ring and a lower cap abutting so as to cover the bottomed casing are sequentially inserted and connected to the outer peripheral side surface of the lower cap by caulking an end surface of the packing case. 5. The rotary according to claim 4, wherein an inner surface of the outer cylindrical portion of the packing case and an outer surface of at least one of the outer surfaces of the bearing and the bottomed casing are fixed with an adhesive. damper. 6. A casing and a bearing constituting a pressure-resistant wall are inserted into a packing case formed in a cylindrical shape with a bottom so as to accommodate a vane body coupled to a shaft, and the casing and the bearing are fitted at the center of the pair of casings and the bearing. A rotatable shaft, to which the vane body is connected, is inserted rotatably, the inside is sealed by an oil seal interposed at the bottom of the packing case, and extends from the shaft side with a separate block provided on the inner peripheral surface of the casing. In the main body structure of the rotary damper in which the casing is partitioned into a plurality of oil chambers with the vane, the oil chamber partitioned by the vane is provided in parallel with a check valve that suctions hydraulic oil from a passage in the vane communicating with the tank chamber. The orifice provided on the outer peripheral side farther from the tank chamber than the check valve. Tally damper.