JP2009250261A - Metal bellows accumulator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a metal bellows accumulator having improved durability and stability of a sealing member by preventing a lip section of the sealing member from being pinched between a cap and an oil port in a 0-down state where metal bellows is contracted. <P>SOLUTION: In the metal bellows accumulator, the sealing member comprises: a holding means, which holds the sealing member at the oil port side; a metal reinforcement ring arranged between the cap and the oil port; a first seal protrusion of an elastic material, which is provided integrally with the metal reinforcement ring and projected to the cap side; and a second seal protrusion of the elastic material, which is provided integrally with the metal reinforcement ring and projected to the oil port side. The first seal protrusion is configured to be positioned inward in the radial direction from the second seal protrusion. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

The present invention relates to a metal bellows type accumulator.
The present invention also relates to a metal bellows accumulator that partitions a variable volume gas chamber in a shell with a metal bellows and accumulates hydraulic fluid.
Furthermore, the present invention relates to a metal bellows accumulator useful for accumulating hydraulic fluid of a hydraulic source of a control device such as a vehicle using hydraulic pressure, such as an anti-lock brake device, at a high pressure.

Conventionally, a metal bellows type accumulator shown in FIGS. 6 to 8 is known.
In this kind of metal bellows type accumulator, a metal material bellows 40 is disposed in a metal material shell 10.

One end of the metal bellows 40 is welded and integrated with an annular flange portion 100 provided in the shell 10.
On the other hand, the other end of the metal bellows 40 is closed by the cap 50 being fixed by welding.

As a result, the inside of the shell 10 is partitioned into a gas chamber 20 and a liquid chamber 30.
Nitrogen gas, inert gas, or the like is sealed in the gas chamber 20 from an injection hole 110 located in the upper part of the figure. The injection hole 110 is closed by a gas plug 130 after the gas is sealed.
As a result, the gas chamber 20 is filled with a gas having a predetermined pressure.

On the other hand, the liquid chamber 30 communicates with an introduction hole 60 for introducing a liquid located in the lower part of the figure.
An external working fluid is guided to the liquid chamber 30 through the introduction hole 60.
Further, an annular seal member 70 made of an elastic material is disposed inside the shell 10 of the introduction hole 60 so as to surround the introduction hole 60.

The seal member 70 is in sealing contact with the cap 50 in order to prevent the bellows from contracting excessively when the pressure of the working fluid is greatly reduced rather than the gas pressure.
As a result, the liquid in the liquid chamber 30 and the liquid on the introduction hole 60 side are blocked.
On the other hand, a damping ring 90 is held on the cap 50 in order to suppress the radial deflection of the metal bellows 40 and guide the axial direction in the shell 10 when the metal bellows 40 is extended or contracted. ing.

  Then, as shown in FIG. 7, when the lip portion 710 contacts the cap 50, the conventional seal member 70 loses escape from the liquid pressure on the liquid chamber 30 side, so that the lip portion 710 is pushed out to the introduction hole 60 side. Is affected.

As a result, as shown in FIG. 8, the tip of the lip 710 is deformed so as to be sandwiched in the gap 81 between the inner peripheral end of the oil port 80 and the cap 50.
For this reason, when the cap 50 is further lowered to the oil port 80 side, a problem that the lip portion 710 is damaged is caused.
Further, since the seal member 70 is made of a single rubber-like elastic material, when the differential pressure between the liquid chamber 30 side and the introduction hole 60 side becomes extremely large, or the flow velocity of the working fluid flowing in the vicinity of the seal member 70 If the speed is too fast, there is a risk that the sealing member 70 itself jumps out of the holding groove of the oil port 80.

JP 2007-187229 A JP 2000-356201 A JP 2007-218352 A

  The present invention has been made in view of such a problem, and in the 0-down state in which the metal bellows contracts, the lip portion of the seal member is prevented from being sandwiched between the cap and the oil port, An object of the present invention is to provide a metal bellows type accumulator in which durability and stability of a seal member are improved.

The metal bellows type accumulator of the present invention is separated into a gas chamber and a liquid chamber by being disposed in the shell, one end being fixed to the shell side and the other end being closed by a cap. A metal bellows, and an oil port arranged to surround an introduction hole for introducing a liquid into the liquid chamber, an oil port defining a contraction limit of the metal bellows, and an oil port end face, In a metal bellows type accumulator comprising a seal member that seals between the liquid chamber and the introduction hole by being in contact with a cap,
The seal member is provided integrally with the metal reinforcement ring, a holding means for holding the seal member on the oil port side, a metal reinforcement ring disposed between the cap and the oil port, and A first seal protrusion made of an elastic material protruding toward the cap side, and a second seal protrusion made of an elastic material protruding toward the oil port provided integrally with the metal reinforcement ring, The first seal protrusion is positioned radially inward from the second seal protrusion.

The present invention has the following effects.
According to the metal bellows type accumulator of the first aspect of the present invention, since the first seal protrusion of the seal member is positioned radially inward of the second seal protrusion, the liquid chamber of the seal member The pressure receiving area where the pressure acts is larger on the first seal projection side.
As a result, the pressure in the liquid chamber acts to press the seal member against the oil port side, so that the seal member does not separate from the oil port side.
Moreover, according to the metal bellows type accumulator of the invention described in claim 2, the seal member can be reliably held on the oil port side.
Furthermore, according to the metal bellows type accumulator of the invention described in claim 3, since the seal holder is directly fitted to the oil port, the seal member can be reliably held on the oil port side.

Furthermore, according to the metal bellows type accumulator of the invention described in claim 4, the integration of the seal member and the seal holder can be achieved more reliably.
Furthermore, according to the metal bellows type accumulator of the fifth aspect of the present invention, it is possible to reliably prevent the seal member from being lifted.

According to the metal bellows type accumulator of the invention described in claim 6, since the seal holder is directly fitted to the oil port, the seal member can be reliably held on the oil port side.
Moreover, according to the metal bellows type accumulator of the seventh aspect of the invention, the seal holder can be securely fixed to the oil port side, so that the holding of the seal member is stabilized.
According to the metal bellows type accumulator of the eighth aspect of the present invention, there is no risk that the bonding interface between the metal reinforcing ring and the elastic member is eroded by the working fluid.
According to the metal bellows type accumulator of the invention according to claim 9, the sealing performance of the sealing member is stabilized.
According to the metal bellows type accumulator of the tenth aspect, leakage of the working fluid from the liquid chamber side to the introduction hole side can be reliably prevented.
Further, according to the metal bellows type accumulator of the eleventh aspect of the present invention, the impact applied to the holding means when the valve is opened can be reduced, so that the holding means can be prevented from being deformed or damaged.

Hereinafter, the best mode for carrying out the present invention will be described.
A metal bellows type accumulator according to the present invention will be described with reference to FIGS.
FIG. 1 is a longitudinal sectional view of a metal bellows accumulator according to the present invention.
FIG. 2 is a partially enlarged view of FIG.
FIG. 3 is a view showing another embodiment of the present invention in the same manner as FIG.
FIG. 4 shows another embodiment of the present invention in the same manner as FIG.
FIG. 5 shows another embodiment of the present invention in the same manner as FIG.

1 and 2, the metal shell 1 includes a cup-shaped main body 12 and an oil port 8 provided with a fluid introduction hole 6 that closes the lower portion of the main body 12 in the figure.
The flange portion 10 of the oil port 8 is integrated with the main body 12 by welding.

On the other hand, a metal bellows 4 is disposed in the shell 1.
As this kind of metal material bellows 4, a metal thin film having a predetermined film pressure is deposited by plating on the core surface in which crests and troughs continuous in the circumferential direction are repeatedly formed. Electrodeposited bellows obtained by dissolving and removing, molded bellows formed by plastic processing of thin metal tubes, or a number of thin metal disks having inner peripheral holes arranged adjacent to each other in the axial direction Also, a welded bellows or the like in which the outer peripheral edges are alternately welded is employed.
One end of the metal bellows 4 is welded and integrated with an annular flange portion 10 provided in the shell 1.

On the other hand, the other end of the metal bellows 4 is closed by the cap 5 being fixed by welding.
As a result, the inside of the shell 1 is partitioned into a gas chamber 2 and a liquid chamber 3.
The gas chamber 2 is filled with nitrogen gas, inert gas, or the like from an injection hole 11 located in the upper part of the figure.
The injection hole 11 is closed with a gas plug 13 after sealing the gas.
As a result, the gas chamber 2 is filled with a gas having a predetermined pressure.

On the other hand, the liquid chamber 3 communicates with an introduction hole 6 provided in the oil port 8 for introducing a liquid.
An external working fluid is guided to the liquid chamber 3 through the introduction hole 6.
Further, inside the shell 1 of the introduction hole 6, a seal member 7 is disposed at an end portion in the axial direction of the oil port 8 (upward in the drawing) so as to surround the introduction hole 6.
On the other hand, in order to suppress radial deflection of the metal bellows 4 and guide the axial direction in the shell 1 during the expansion / contraction operation of the metal bellows 4, the cap 5 has a damping ring 9. Is held.

And the damping ring 9 which concerns on this invention is a collar part by the nail | claw part 91 fitted in the trough part 41 of the metal-made bellows 4, and the fixing | fixed part 92 contact | abutted to the cyclic | annular collar part 51 provided in the cap 5. The cap 51 is held on the side of the cap 5 so as to sandwich it.
A protection ring 14 made of the same material and having the same thickness as that of the claw portion 91 of the damping ring 9 is fitted in the trough portion 41 between the metal bellows 4 and the flange 10.

  On the other hand, the seal member 7 includes a holding means 74 for holding the seal member 7 on the oil port 8 side, a metal reinforcing ring 71 disposed between the cap 5 and the oil port 8, and the metal reinforcing ring 71. A first seal protrusion 72 made of an elastic material projecting toward the cap 5 provided integrally, and a second seal made of an elastic material projecting toward the oil port 8 provided integrally with the metal reinforcement ring 71. And a seal projection 73.

The first seal protrusion 72 is positioned radially inward from the second seal protrusion 73.
For this reason, the pressure receiving area where the pressure of the liquid chamber 3 acts on the seal member 7 is larger on the first seal protrusion 72 side.
As a result, the pressure in the liquid chamber 3 acts to press the seal member 7 against the oil port 8 side.

The holding means 74 for holding the seal member 7 on the oil port 8 side has a cylindrical portion 711 extending downward in the figure along the outer peripheral surface of the oil port 8 from the radial outer side of the metal reinforcing ring 71. The reduced diameter part 712 which enters the hollow part 81 provided in the outer peripheral surface of the oil port 8 was provided in the lower end part of this cylindrical part 711.
Thus, the seal member 7 is securely held on the oil port 8 side.
Further, as the material of the seal protrusions 72 and 73, rubber-like elastic bodies such as EPDM, NBR, and CR, and resin-like elastic bodies such as fluororesin and polyethylene resin are appropriately selected and used depending on the atmosphere to be used.

The first seal projection 72 can effectively prevent the liquid on the liquid chamber 3 side from flowing out to the introduction hole 6 side after contacting the cap 5 (during bellows zero down).
For this reason, the surface of the first seal projection 72 that contacts the cap 5 is a flat surface 721 that is substantially parallel to the surface of the cap 5.
Further, the inner peripheral inclined surface 722 forming the first seal projection 72 is a gentle inclined surface as compared with the outer peripheral inclined surface 723.
This can more effectively prevent the liquid on the liquid chamber 3 side from flowing out to the introduction hole 6 side.
The second seal protrusion 73 serves to prevent fluid from leaking from the gap between the seal member 7 and the oil port 8.

Since the metal reinforcing ring 71 is entirely covered with the elastic material, there is no risk that the bonding interface between the metal reinforcing ring 71 and the elastic material is eroded by the working fluid.
Next, another embodiment of the present invention will be described with reference to FIG.
The holding means 74 in the present embodiment is a seal holder 82 fixed to the inner peripheral surface side of the oil port 8.
The seal holder 82 includes a holding flange 821 that holds the radially inner end 713 of the metal reinforcing ring 71.

Then, when the seal holder 82 is fitted and fixed to the inner peripheral surface of the oil port 8, the holding flange 821 presses the radially inner end 713 toward the oil port 8, and the seal member 7 is moved to the oil port 8. Secure to the side.
Further, since the holding means 74 includes a cylindrical portion 714 extending from the radially outer side of the metal reinforcing ring 71 along the outer peripheral surface of the oil port 8, the seal member 7 is lifted from the oil port 8 side. It can be stopped more reliably.

Still another embodiment of the present invention will be described with reference to FIG.
In this embodiment, the holding means 74 includes a cylindrical portion 715 extending from the radially outer side of the metal reinforcing ring 71 along the outer peripheral surface of the oil port 8, and a radially outer side from the axial end portion of the cylindrical portion 715. The seal member 7 is held on the oil port 8 side by pressing the radial flange 716 extending toward the oil port 8 side by the holding flange 822 of the seal holder 83 held on the outer peripheral surface side of the oil port 8. It is said.
The seal holder 83 is fixed to the oil port 8 side with a reduced diameter portion 831 provided at one end of the seal holder 83 engaged with a recess 84 provided on the outer peripheral surface of the oil port 8.
Furthermore, still another embodiment of the present invention will be described with reference to FIG.
4 differs from FIG. 4 in that a gap W of about 0.5 mm is provided between the holding flange 822 and the radial flange 716 of the seal holder 83 and the radial inner end of the holding flange 822 from the radial inner end of the seal member 7. A cylindrical guide 823 extending upward along the outer peripheral surface of the cylindrical portion 715 is provided.
The reason for this structure is as follows.
Since the seal member 7 receives force in the valve opening direction (upward in the figure) until the valve is opened due to the pressure at the time of valve opening, in the structure shown in FIG. The valve opening pressure is immediately applied to the holding flange 822 in contact with the radial flange 716.
As a result, there is a concern that the holding flange 822 may be deformed or damaged.
However, by providing a gap W (about 0.5 mm in this case) between the radial flange 716 and the holding flange 822, even if the seal receives force in the valve opening direction until the valve is opened. Since there is a gap W between the holding flange 822 and the radial flange 716, a force due to the valve opening pressure is not applied to the holding flange 822.
When the seal member 7 moves in the axial direction due to the pressure at the time of valve opening, the lip 73 on the bottom surface of the seal is separated from the oil port 8, and the valve opening pressure also flows to the outer periphery of the seal, so the valve opens smoothly. The holding flange 822 does not have to be deformed or damaged.
Similarly, in the embodiments of the other modes shown in FIGS. 1 to 3, a mode in which the holding means 74 holds the seal member 7 so as to be axially movable with respect to the oil port 8 (a mode in which the gap W is provided) preferable.
The shapes of the first seal protrusion 72 and the second seal protrusion 73 shown in FIGS. 3 and 5 are the same as those shown in FIG.

  Further, the present invention is not limited to the best mode for carrying out the invention described above, and various other configurations can be adopted without departing from the gist of the present invention.

It is a longitudinal cross-sectional view of the metal bellows type accumulator which concerns on this invention. It is the elements on larger scale of FIG. It is the figure which showed the other Example of this invention similarly to FIG. It is the figure which showed the further another Example of this invention similarly to FIG. FIG. 5 is a view showing still another embodiment of the present invention in the same manner as FIG. 4. It is a longitudinal cross-sectional view of the metal bellows type accumulator which concerns on a prior art. It is the elements on larger scale of FIG. It is the figure which showed the state by which the lip | rip part of FIG. 7 was pinched | interposed into the gap.

Explanation of symbols

1 shell
2 Gas chamber 3 Liquid chamber 4 Metal bellows 5 Cap 6 Introduction hole 7 Seal member 8 Oil port 9 Damping ring 10 Flange portion 11 Injection hole 12 Body 13 Gas plug 14 Protection ring 71 Metal reinforcement ring 72 First seal projection 73 First 2 sealing projections 74 holding means

Claims (11)

The shell (1) is disposed in the shell (1), one end is fixed to the shell (1) side, and the other end is closed by the cap (5), thereby the shell (1) is closed to the gas chamber. The metal bellows (4) separated into (2) and the liquid chamber (3) and the introduction hole (6) for introducing the liquid into the liquid chamber (3) are disposed so as to surround the metal bellows (4). An oil port (8) that defines the shrinkage limit of the material bellows (4) and an end face of the oil port (8) are arranged in contact with the cap (5), thereby the liquid chamber (3) and the introduction hole. (6) In a metal bellows type accumulator comprising a seal member (7) for sealing between
The seal member (7) is disposed between a holding means (74) for holding the seal member (7) on the oil port (8) side, and between the cap (5) and the oil port (8). A metal reinforcing ring (71) that is formed, a first seal protrusion (72) made of an elastic material protruding integrally with the metal reinforcing ring (71) and projecting toward the cap (5), and the metal reinforcing ring A second seal protrusion (73) made of an elastic material protruding integrally to the oil port (8) provided integrally with the ring (71), and the first seal protrusion (72) is the first seal protrusion (72). A metal bellows type accumulator, which is located radially inward from the two seal projections (73).   The holding means (74) includes a cylindrical portion (711) extending along the outer peripheral surface of the oil port (8) from the radially outer side of the metal reinforcing ring (71), and the cylindrical portion ( The metal bellows type accumulator according to claim 1, wherein a reduced diameter portion (712) that engages with a recess portion (81) provided on an outer peripheral surface of the oil port (8) is provided at an end portion of the oil port (8). .   The metal bellows accumulator according to claim 1, wherein the holding means (74) is a seal holder (82) fixed to the inner peripheral surface side of the oil port (8).   The metal bellows type according to claim 3, wherein the seal holder (82) includes a holding flange (821) for holding a radially inner end (713) of the metal reinforcing ring (71). accumulator.   The said holding means (74) is provided with the cylindrical part (714) extended along the outer peripheral surface of the said oil port (8) from the radial direction outer side of the said metal reinforcement ring (71). Item 5. A metal bellows accumulator according to Item 4.   The holding means (74) includes a cylindrical portion (715) extending along the outer peripheral surface of the oil port (8) from the radially outer side of the metal reinforcing ring (71), and the cylindrical portion (715). The radial flange (716) extending radially outward from the axial end is held by a seal holder (83) held on the outer peripheral surface side of the oil port (8). The metal bellows type accumulator according to claim 1.   In the seal holder (83), a reduced diameter portion (831) provided at one end of the seal holder (83) engages with a recess portion (84) provided in an outer peripheral surface of the oil port (8), so that the oil The metal bellows type accumulator according to claim 6, wherein the metal bellows type accumulator is fixed to the port (8) side.   The metal bellows type accumulator according to any one of claims 1 to 7, wherein the metal reinforcing ring (71) is entirely covered with an elastic material.   The surface of the first seal projection (72) in contact with the cap (5) is a flat surface (721) substantially parallel to the surface of the cap (5). A metal bellows type accumulator according to claim 1.   The inner peripheral inclined surface (722) forming the first seal projection (72) is a gentle inclined surface as compared with the outer peripheral inclined surface (723). The metal bellows type accumulator described in the item.   The said holding | maintenance means (74) hold | maintains the said sealing member (7) so that an axial direction movement is possible with respect to the said oil port (8). Metal bellows type accumulator.

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