JP3434303B2 - Accumulator device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a use for storing pressure or absorbing a pulsation of a hydraulic pressure in a facility utilizing the pressure of a fluid such as various hydraulic devices. The present invention relates to an accumulator device suitable for the present invention. 2. Description of the Related Art In a conventional hydraulic circuit, an accumulator device 200 as shown in FIG. 8 is sometimes used as a means for absorbing a hydraulic pulsation generated by driving a hydraulic pump or the like. In the accumulator device 200, a partition member 205 is housed inside a housing 204 including a cylindrical shell 201 and a bottom base member 202, and the inside of the housing 204 is separated by the partition member 205 into a liquid chamber.
It is divided into 206 and air chamber 207. Oil is introduced into the liquid chamber 206 from the liquid inlet 210. Gas supply port in air chamber 207
The compressed gas is supplied from 211. The gas supply port 211 is closed by a gas sealing plug 212. The partition member 205 includes a metal bellows 215 and a bellows cap 216.
The fixed end 217 of the bellows 215 is joined to the bottom base member 202 by welding over its entire circumference, and the free end 218
Is joined to the bellows cap 216 by welding all around. A bellows cap 216 is provided with a sealing member.
220 are provided. When gas is supplied to the air chamber 207, the bellows 215 extends fully and comes into close contact with the seal seating surface 222 near the liquid introduction port 210, so that the outer peripheral surface of the bellows 215 and the inner peripheral The back-up oil is confined to the surface. The seal member 220 and the seal seat surface 222 constitute a self-sealing mechanism 223. The backup oil confined by the self-sealing mechanism 223 supports the outer surface of the bellows 215 against the gas filling pressure in the air chamber 207, and prevents the bellows 215 from being deformed. The seal member 220 is made of a rubber-like elastic material such as NBR, and has a bellows cap.
216 is fixed by vulcanization and adhesion. [0004] In the accumulator device 200, in order to maintain a predetermined performance for a long period of time, an air chamber is required.
It is imperative that gas does not leak from 207,
Therefore, it is important to control the quality of the weld at both ends 217 and 218 of the bellows 215 to a high degree. Since the quality of the welded portion cannot be determined from the appearance, it was necessary to perform a leak test or the like after welding to ensure a predetermined quality.
In addition, the welding speed cannot be too high to obtain a weld of constant quality. For this reason, the manufacture of the conventional accumulator apparatus 200 is inefficient, and has been an obstacle in reducing the manufacturing cost. If brazing joining using a high-frequency induction heating or a heating furnace can be applied instead of the above-mentioned welding, the joining becomes easy and the quality of the joining portion can be easily controlled. In this case, since the temperature around the joint becomes high over a wide range, the seal member 220 provided on the bellows cap 216 may be affected by the temperature and deteriorate. SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a high-quality accumulator with a built-in bellows, which can be manufactured efficiently without welding. In order to achieve the above object, the present invention provides a housing having a liquid inlet, a fixed end accommodated in the housing and hermetically joined to a base member. A bellows main body having a free end displaceable in the axial direction of the bellows, an air chamber surrounded by an inner peripheral surface of the bellows main body and supplied with gas from a gas supply port, and an outer peripheral surface of the bellows main body and the inside of the housing. A liquid chamber surrounded by a peripheral surface and supplied with liquid from the liquid inlet, and a seal seat provided on a free end side of the bellows body and near the liquid inlet when the bellows body is extended by a predetermined amount. An accumulator device having a self-sealing mechanism that closes the liquid between the inner peripheral surface of the housing and the outer peripheral surface of the bellows body by being in close contact with the surface. The bellows mechanism is formed integrally with the bellows body on the free end side of the bellows body or joined to the bellows body by brazing to close the free end of the bellows body, and It was created as a separate body
The cap body, which is located on the outer surface of the bellows end plate
In a state where the bellows end plates are overlapped in the thickness direction,
The outer peripheral portion is the bellows end plate or the bellows body or
Bellows end plate by bending part of the adapter
A cap body that is fixed, is bonded to the seal seat surface opposed to the position of the cap body seal
And a member. The compressed gas is sealed in the air chamber. Although the sealing performance of the air chamber depends on the bellows body and the bellows end plate, the bellows body and the bellows end plate are air-tightly joined by integral molding or brazing. Can be determined. Since the bellows end plate is a metal part without a seal member attached, there is no risk of material deterioration even when heated to a high temperature. Therefore, even if the temperature of the entire bellows end plate rises like brazing, there is no problem. Absent. For this reason, the bellows end plate and the bellows main body can be joined by a soft solder or a hard solder, so that the process can be simplified and the quality control of the joint can be facilitated. Further, instead of brazing, the bellows end plate can be formed integrally with the bellows body by blow molding or the like. Since the cap body fixed to the bellows end plate does not affect the sealing of the air chamber, the mounting part of the cap body should be provided with relatively simple fixing means such as caulking, bonding or screwing. Applicable. A first embodiment of the present invention will be described below with reference to FIGS. The accumulator device 10 shown in FIG. 1 is used for, for example, absorbing hydraulic pulsation generated in hydraulic equipment and storing pressure. The housing 11 of the accumulator device 10
Is a metal shell 1 made into a cylindrical shape by forging or the like.
2 and a metal bottom base member 13 inserted into an opening 12 a at one end (lower side in the figure) of the shell 12. The housing 11 has rigidity to withstand the working pressure of the hydraulic device acting on the accumulator device 10. A liquid inlet 14 is provided in the shell 12. A gas supply port 15 is provided in the bottom base member 13. The gas supply port 15 is closed by a gas sealing plug 17 provided with a sealing material 16. The bottom base member 13 is fixed to a predetermined position of the shell 12 by a retaining ring 20 for retaining. Since the fixing is performed by the retaining ring 20, the fixing operation can be completed in a shorter time than in the case where the shell 201 and the bottom base member 202 are fixed by welding as in the conventional accumulator device (FIG. 8). A seal member 22 such as an O-ring is inserted into an annular groove 21 provided in the bottom base member 13. Reference numeral 23 denotes a waterproof cap made of a synthetic resin. The waterproof cap 23 is press-fitted into the one end opening 12 a of the shell 12. A partition member 30 is provided inside the housing 11.
The partition member 30 partitions the interior of the housing 11 into an air chamber 31 and a liquid chamber 32. The partition member 30 includes a metal bellows main body 35 that can expand and contract in the axial direction of the housing 11, a metal bellows end plate 36, a metal cap body 37, and a seal member 38. The material of the bellows body 35 and the bellows end plate 36 is, for example, austenitic stainless steel, and the thickness of each is about 0.1 mm to 0.5 mm. The bellows main body 35 is provided with the bottom base member 1.
3 has a fixed end 41 hermetically joined over the entire circumference and a free end 42 that is displaceable in the axial direction of the housing 11. The space on the inner peripheral side of the bellows body 35 is the air chamber 3.
Used as 1. The space between the outer peripheral surface of the bellows body 35 and the inner peripheral surface of the housing 11 is used as the liquid chamber 32. Oil is introduced into the liquid chamber 32 through the liquid inlet 14. An inert gas such as nitrogen or helium is sealed in the air chamber 31 at a pressure higher than the atmospheric pressure. This gas is supplied to the air chamber 31 through the gas supply port 15.
The gas supply port 15 is airtightly closed by a gas sealing plug 17 after the gas is supplied. The free end 42 of the bellows body 35 is airtightly closed by the bellows end plate 36. Cap body 37 attached to the outer surface of bellows end plate 36
The seal member 38 is fixed to the end face of the seal member 38. The seal member 38 is made of a rubber-like elastic material such as NBR or urethane elastomer. When a gas is supplied to the air chamber 31, the partition member 30 extends due to the gas pressure, and the seal seat surface near the liquid inlet 14. By being in close contact with 45, backup oil is sealed between the outer peripheral surface of the bellows main body 35 and the inner peripheral surface of the shell 12. I mean,
The cap body 37, the seal member 38, the seal seat surface 45, and the like constitute a self-sealing mechanism 46. The bellows body 35 and the bellows end plate 36 are fixed by brazing. The cap body 37 is fixed to the bellows end plate 36 by bending an edge 50 of the bellows end plate 36 inward as an example of a fixing means. As shown in FIG. 2, the brazing of the bellows body 35 and the bellows end plate 36 is performed by setting a foil brazing material 51 between the end face 52 of the bellows body 35 and the bellows end plate 36 over the entire circumference. In this state, the brazing material 51 is heated to a temperature at which the brazing material 51 is melted by an appropriate heating means such as the high-frequency induction coil 55. The brazing material 51 has an annular shape concentric with the bellows body 35, and the outer diameter of the brazing material 51 is smaller than the outer diameters of the bellows body 35 and the bellows end plate 36. As shown in FIG. 3, the bellows body 35 and the bellows end plate 36 are hermetically joined over the entire circumference.
In this case, the quality of the joining quality can be determined by visually observing the outer peripheral portion 51b of the brazed solder 51a from the outside. After brazing, the cap body 37 is fixed by bending the edge 50 of the bellows end plate 36 inward as shown in FIG. A seal member 38 is fixed to the cap body 37 in advance by an appropriate attachment means such as vulcanization or adhesion. The manufacturing process of the accumulator device 10 is as described below. The bellows body 35 and the bellows end plate 36 are joined by the above-mentioned brazing. Further, the fixed end 41 of the bellows body 35 is brazed to the bottom base member 13. The brazing of the fixed end 41 is performed between the bellows body 35 and the bottom base member 13.
The bellows body 35 and the bottom base member 13 are heated by a high-frequency induction coil in the same manner as the brazing of the bellows end plate 36 with an annular foil brazing having an outer diameter smaller than the outer diameters of the bellows 5 and the bottom base member 13 interposed therebetween. And brazing. After the above two brazing operations, the cap body 37 is placed on the bellows end plate 36 and the bellows end plate 3
The cap body 37 is fixed to the bellows end plate 36 by caulking the edge 50 of FIG. 6 as shown in FIG. The cap body 37 may be fixed by bonding. After the seal member 22 is mounted in the annular groove 21 of the bottom base member 13, the partition member 30 and the bottom base member 13 are inserted into the housing 11, and
0 fixes the bottom base member 13. Then, a predetermined compressed gas is supplied from the gas supply port 15 to the gas chamber 31 with the liquid chamber 32 filled with the backup liquid, and then the gas supply port 15 is closed by the gas sealing plug 17. The bellows body 35 extends in the axial direction due to the gas filling pressure, and when the gas pressure exceeds a certain value, the seal member 38 comes into close contact with the seal seat surface 45. Therefore, the liquid is confined between the inner peripheral surface of the shell 12 and the outer peripheral surface of the bellows main body 35, and the bellows main body 35 is supported from the outer surface side, so that the bellows main body 35 is prevented from being deformed. According to the accumulator device 10 having the above-described structure, the bellows end plate 36 and the bellows main body 35 whose temperatures rise during brazing are made of only metal, so that there is no problem even if they are exposed to high temperatures. Therefore, even if the sealing member 38 made of a rubber-like elastic body is attached to the cap body 37, the bellows main body 35 and the bellows end plate 36 can be hermetically joined by brazing. In addition to using the brazing material 51 having a smaller diameter than the outer diameter of the brazed joint, the quality of the joint can be easily determined by an appearance inspection performed after brazing. For this reason, it is possible to omit the leak inspection required for the conventional welding. In addition, since the brazing is performed by high-frequency induction heating, the working time can be reduced as compared with the conventional joining by welding, and the manufacturing tact time is improved. In performing the above brazing,
Heating means other than high-frequency induction heating may be employed. For example, when SUS304 is used as the material of the bellows main body 35, the brazing in a continuous furnace is performed by using an appropriate brazing material within a temperature range or a temperature rising time in which the work hardening generated at the time of forming the bellows main body 35 can be maintained. May be carried out. The bellows body 35 and the bellows end plate 3
6 and the bellows body 35 and the bottom base member 13 are not limited to hard brazing, but may employ a joining method using soft solder such as soldering. For example, when the bellows body 35 is made of phosphor bronze, in order to prevent the bellows body 35 from deteriorating its durability due to the heat effect at the time of brazing, soft brazing performed at a low temperature such as soldering is used. Is valid. When such a joining method is adopted, in addition to the above-described high-frequency induction heating, mass production using a continuous furnace becomes possible, and the production cost can be further reduced. In addition, the inspection of the joint can be performed by visual inspection, and the quality check step by the leak inspection required for the conventional welding can be eliminated. Next, a second embodiment of the present invention will be described with reference to FIG.
This will be described with reference to FIG. The metal housing 61 of the accumulator device 60 of this embodiment includes a cylindrical shell 62, a shell cap 63 welded to one end of the shell 62, and a bottom base member 64 welded to the other end of the shell 62. It is configured. A liquid inlet 70 is provided in the shell cap 63. A gas supply port 71 is provided in the bottom base member 64. A gas filling plug 73 provided with a sealing material 72 is screwed into the gas supply port 71. The shell 62 and the shell cap 6
Instead of the third base member 64 and the bottom base member 64, a structure in which the bottom base member 13 is fixed to the shell 12 by the retaining ring 20 as in the housing 11 described in the first embodiment may be employed. A partition member 80 is provided inside the housing 61. The partition member 80 includes a metal bellows main body 81. Fixed end 82 of bellows body 81
Is airtightly joined to the bellows fixing portion 83 of the bottom base member 64 over the entire circumference by brazing. A free end 84 of the bellows main body 81 is provided with a bellows end plate 87, a cap body 88, and a seal member 89.
The bellows body 81 and the bellows end plate 87 are connected to the first
The bellows body 35 and the bellows end plate 36 of the embodiment may be the same, but the material and the plate thickness are appropriately selected as needed. The space inside the partition member 80 is used as an air chamber 91, and a compressed inert gas such as nitrogen or helium is sealed in the air chamber 91 from a gas supply port 71.
A space surrounded by the outer peripheral surface of the partition member 80, the inner peripheral surface of the shell 62, and the inner surface of the shell cap 63 is used as the liquid chamber 92. A working fluid such as oil is introduced into the fluid chamber 92 from the fluid introduction port 70. The seal member 89 attached to the cap body 88 is made of a rubber-like elastic material such as NBR or elastomer. When the high-pressure gas is supplied to the air chamber 91, the seal member 89 is pressed by the bellows body 8 by the pressure of the gas.
1 is in close contact with the seal seat surface 93 in the extended state. As a result, the backup liquid is confined between the inner peripheral surface of the shell 62 and the outer peripheral surface of the bellows main body 81, and the bellows main body 81 is supported from the outer surface side by this liquid. Is prevented. That is, the cap body 88, the seal member 89, and the seal seat surface 93 constitute a self-sealing mechanism 95. As an example of the fixing means, the cap body 88 is fixed to the bellows main body 81 by bending an edge 96 of the bellows main body 81 inward. The bellows body 81 and the bellows end plate 87 are fixed by brazing. The bellows body 81 and the bottom base member 64 are also fixed by brazing. As shown in FIG. 5, the bellows body 81
The solders 98, 99 are set at the corners of both end edges 96, 97, and heated to a temperature at which the waxes 98, 99 are melted by an appropriate heating means such as a heating furnace controlled at a predetermined temperature. The bellows body 81 and the bellows end plate 87 are airtightly joined over the entire circumference, and the bellows body 81 and the bottom base member 64 are airtightly joined over the entire circumference. After brazing, the cap body 88 is placed on the bellows end plate 87, and the upper end edge 96 of the bellows body 81 is bent toward the edge of the cap body 88, so that the cap body 88 is fixed. According to the accumulator device 60 having the above-described structure, the bellows body 81, the bellows end plate 87, and the bottom base member 64 made of only metal are heated by a high-frequency induction heating or a heating furnace in a state where the sealing member 89 is separated. Therefore, the joining portion can be brazed as in the first embodiment. In the case of the second embodiment, the upper and lower brazing points are simultaneously performed, and the brazing can be continuously processed using a continuous furnace, so that mass production is possible. FIG. 6 shows a third embodiment of the present invention. In this accumulator device 105, a partition member 112 having a polymer bellows body 111 is accommodated in a housing 110. The polymer bellows body 111 is inferior to a metal bellows in gas barrier properties, but can be used in practice unless a long-term performance guarantee is required. The metal housing 110 of this embodiment comprises a shell 115 and a bottom base member 116 inserted into one end opening 115a of the shell 115. Bottom base member 11
6 is held at a predetermined position on the shell 115 by a retaining ring 117. A seal member 120 and a backup ring 121 are provided between the shell 115 and the bottom base member 116. A liquid inlet 125 is provided in the shell 115.
The bottom base member 116 has a gas supply port 126 and a gas supply port.
A gas filling plug 127 closing the 126 is provided. A sealing member 128 is provided on the gas sealing plug 127. The partition member 112 has a fixed end 131 and a free end 13.
2 and a metal adapter 135 provided on the free end 132 side of the bellows body 111.
And a cap body 136 fixed to the adapter 135,
It comprises a seal member 137 attached to the cap body 136 and the like. The bellows end plate 140 is formed integrally with the bellows main body 111 by blow molding or the like. Male thread 1 on the outer periphery of the free end 132 of the bellows body 111
41 is provided.
The adapter 135 is screwed together with an adhesive if necessary, so that the adapter 135 is attached to the bellows body.
It is fixed to 111. As an example of the fixing means, the cap body 136 is fixed to the bellows main body 111 via the adapter 135 by bending the edge portion 143 of the adapter 135 inward and caulking. The bellows body 111 and the adapter 135 may be fixed to each other by caulking or bonding so as not to fall off from each other. The fixed end 131 of the bellows main body 111 is pressed from the outer peripheral side by a pressing member 145, and is fixed between the fixed end 131 of the bellows main body 111 and the end 146 of the bottom base member 116.
1 is sandwiched all around. The procedure for assembling the accumulator device 105 of the third embodiment having such a configuration is as follows. First, the adapter 135 is fixed to the partition member 112. Then, place the cap body 136 on the adapter 135, and
The cap body 136 is fixed by bending the edge 143 of No. 5 inward by pressing or the like. As shown in FIG. 7, the outer periphery of the cap body 136 may be cut obliquely. A seal 147 is provided on the inner peripheral side of the bellows body 111.
And backup ring 148. After that, a pressing member 145 and a spacer 149 are provided on the outer peripheral side of the bellows body 111.
Is set. The holding member 145 is divided into two parts in the radial direction, and can be mounted on the bellows main body 111 without any problem. The seal member 120 and the backup ring 121 are attached to the bottom base member 116. Bottom base member 11
6 and the partition member 112 are inserted into the housing 110 in a state where they are fitted to each other, and are fixed at a predetermined position by a retaining ring 117 and are prevented from coming off. In addition, the volume of the air chamber 161 is adjusted by injecting an appropriate amount of the volume adjusting liquid 160 into the inside of the partition member 112. The outer peripheral surface of the partition member 112 and the housing 110
The liquid is introduced into a liquid chamber 162 between itself and the inner peripheral surface. Further, gas is supplied to the air chamber 161 from the gas supply port 126. Since the gas is sealed by the sealing material 147, the gas does not leak outside. The gas supply port 126 is closed by a gas sealing plug 127. When the bellows body 111 is extended by the pressure of the gas and the sealing member 137 comes into close contact with the seal seating surface 165, a backup liquid is confined between the outer peripheral surface of the bellows main body 111 and the inner peripheral surface of the shell 115, and the bellows main body 111 is closed.
Deformation is prevented. Therefore, the cap body 136, the seal member 137, and the seal seat surface 165 are self-sealing mechanisms 171.
Is composed. The holding member 145 tightens a portion 166 on the fixed end 131 side of the bellows main body 111 so that the sealing is reliably performed. The position of the pressing member 145 in the axial direction is regulated by a step 172 provided on the inner surface of the shell 115. The partition member of the accumulator device 105
Since the bellows main body 111 constituting 112 can be formed integrally with the bellows end plate 140 by blow molding or the like, the bellows main body 111 can be provided at a lower cost than when a metal bellows is used. In addition, desired airtightness can be managed without performing a leak test which is necessary in the case of joining by welding. According to the present invention, a high-quality accumulator with a built-in bellows can be obtained without welding.
In particular , the seal member that constitutes the self-sealing mechanism is welded
Or deterioration due to heat such as brazing
As a result, the quality control of the bellows joint is easy, and there is a great effect in improving the manufacturing tact time and reducing the cost.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a longitudinal sectional view of an accumulator device showing a first embodiment of the present invention. FIG. 2 is a sectional view showing a state before brazing of a bellows end plate used in the accumulator device shown in FIG. 1; FIG. 3 is a sectional view showing a state where a bellows end plate used in the accumulator device shown in FIG. 1 is brazed. FIG. 4 is a longitudinal sectional view of an accumulator device showing a second embodiment of the present invention. FIG. 5 is a sectional view showing a state before brazing of a bellows main body used in the accumulator device shown in FIG. 4; FIG. 6 is a longitudinal sectional view of an accumulator device according to a third embodiment of the present invention. FIG. 7 is an enlarged sectional view showing a modification of the cap body of the accumulator device shown in FIG. FIG. 8 is a longitudinal sectional view showing a conventional accumulator device. [Description of Signs] 10 ... Accumulator device, 11 ... Housing, 13 ...
Base member, 14: liquid introduction port, 15: gas supply port, 30
... partition member, 31 ... air chamber, 32 ... liquid chamber, 35 ... bellows main body, 36 ... bellows end plate, 37 ... cap body,
38: seal member, 41: fixed end, 42: free end, 45
... seal seat surface, 46 ... self-sealing mechanism, 60 ... accumulator device, 61 ... housing, 64 ... base member, 7
0: liquid inlet, 71: gas supply port, 81: bellows body, 82: fixed end, 84: free end, 87: bellows end plate, 88: cap body, 89: seal member, 91 ...
Air chamber, 92: liquid chamber, 93: seal seat surface, 95: self-sealing mechanism, 105: accumulator device, 110: housing, 111: bellows body, 116: base member, 1
25 liquid inlet, 126 gas supply port, 131 fixed end, 132 free end, 136 cap body, 137
... seal member, 140 ... bellows end plate, 161 ... air chamber,
162: liquid chamber, 165: seal seat surface, 171: self-sealing mechanism.

Continuation of the front page (56) References JP-A-3-107601 (JP, A) JP-A-3-134303 (JP, A) JP-A-2-113139 (JP, A) JP-A-3-302 (JP) , U) JP 5-19601 (JP, U) JP 63-45294 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) F15B 1/00-1/26 F16J 3/00-3/06

Claims (1)

(57) Claims 1. A housing having a liquid inlet, a fixed end accommodated in the housing and hermetically joined to a base member, and a free freely displaceable in the axial direction of the housing. A bellows body having an end, an air chamber surrounded by an inner circumferential surface of the bellows body and supplied with gas from a gas supply port, surrounded by an outer circumferential surface of the bellows body and an inner circumferential surface of the housing, and A liquid chamber to which liquid is supplied from a liquid inlet,
When the bellows body is provided at the free end side of the bellows body and is in a state of being extended by a predetermined amount, the bellows body comes into close contact with a seal seat surface near the liquid introduction port, so that a space between the inner peripheral surface of the housing and the outer peripheral surface of the bellows body is obtained. A self-sealing mechanism for confining the liquid in the accumulator, wherein the self-sealing mechanism is formed integrally with the bellows body at the free end side of the bellows body or joined to the bellows body by brazing. With a bellows end plate that closes the free end of the bellows body, and a cap body made separately from the bellows end plate
And the outer surface of the bellows end plate
The outer peripheral portion is the bellows when
The end plate or part of the bellows body or adapter
A cap body fixed to the bellows end plate by bending, and a position facing the seal seat surface of the cap body.
An accumulator device comprising: a bonded sealing member.