JP2020118169A - Spring structure - Google Patents

Abstract

To provide a technique which can prevent a capacity of supporting a load from sharply dropping.SOLUTION: A spring structure includes a first metallic bellows member, and a circumferential member arranged around the first bellows member and surrounding the first bellows member. Compressible fluid is encapsulated in a sealed space inside the first bellows member. The circumferential member includes a constitution which prevents fluid from flowing from an intermediate space outside the first bellows member and inside the circumferential member to the outside of the circumferential member.SELECTED DRAWING: Figure 1

Description

The technique disclosed in this specification relates to a spring structure.

Patent Document 1 discloses a bellows. The bellows of Patent Document 1 is mainly used as a sealing material.

JP, 11-226658, A

Since the bellows of Patent Document 1 is mainly used as a sealing material, it is not supposed to support the load, but it is also conceivable to use the bellows as part of the spring structure for supporting the load. In that case, it is desirable that the ability of the spring structure to support the load is not compromised. The present specification provides a technique capable of suppressing a sudden decrease in the ability of a spring structure to support a load.

The spring structure disclosed in the present specification may include a first bellows member made of metal, and a peripheral member that is disposed around the first bellows member and surrounds the first bellows member. A compressive fluid may be enclosed in a closed space inside the first bellows member. The surrounding member may include a configuration that suppresses a fluid from flowing out of the intermediate space outside the first bellows member and inside the surrounding member to the outside of the surrounding member.

According to this configuration, even if the first bellows member ruptures due to an increase in the pressure of the compressive fluid enclosed in the closed space inside the first bellows member, for example, the compressible fluid flows out to the outside of the surrounding member. Since it is suppressed, the pressure in the closed space is suppressed from dropping sharply. Therefore, it is possible to prevent the ability of the spring structure to support the load from rapidly decreasing.

The spring structure may further include a pressure sensor that detects the pressure in the intermediate space. With this configuration, it is possible to detect the failure of the spring structure based on the pressure detected by the pressure sensor. For example, when the first bellows member ruptures, the compressible fluid enclosed in the closed space may flow into the intermediate space and the pressure in the intermediate space may increase. When the pressure in the intermediate space is higher than the predetermined threshold value, it can be determined that the spring structure is out of order.

The surrounding member may include a rigid member extending along the axial direction of the first bellows member. According to this configuration, the rigid member can prevent the first bellows member from expanding (that is, buckling) outward.

A surface of the rigid member on the first bellows member side may be coated with a resin layer. With this configuration, it is possible to reduce the frictional resistance between the first bellows member and the rigid member when the first bellows member expands and contracts in the axial direction. Therefore, the first bellows member expands and contracts smoothly in the axial direction.

The surrounding member may be disposed around the first bellows member, and may further include a second metal bellows member surrounding the first bellows member. According to this configuration, even if the first bellows member bursts and the compressible fluid enclosed in the closed space flows out of the first bellows member, the second bellows member suppresses the outflow of the compressible fluid. can do. As a result, it is possible to prevent the pressure in the closed space from rapidly decreasing, and thus it is possible to prevent the ability of the spring structure to support the load from rapidly decreasing.

It is sectional drawing of the spring structure which concerns on 1st Example. FIG. 2 is a sectional view taken along line II-II of FIG. 1. FIG. 3 is an enlarged view of a part III of FIG. 1. FIG. 4 is an enlarged view of part IV of FIG. 3. FIG. 5 is an enlarged view of part V of FIG. 1. It is a figure corresponding to FIG. 5 of the spring structure which concerns on 2nd Example. FIG. 7 is an enlarged view of a part VII of FIG. 6. It is sectional drawing of the spring structure which concerns on 3rd Example. It is sectional drawing of the spring structure which concerns on 4th Example.

(First embodiment)
The spring structure 1 according to the first embodiment will be described with reference to the drawings. As shown in FIG. 1, the spring structure 1 according to the first embodiment includes a first metal bellows member 2 and a peripheral member 90. An upper side support member 11 is arranged above the first bellows member 2, and a lower side support member 12 is arranged below the first bellows member 2. A closed space 51 is formed inside the first bellows member 2. An intermediate space 95 is formed outside the first bellows member 2 and inside the peripheral member 90.

The first bellows member 2 is made of, for example, an alloy containing iron (Fe). The metal of the first bellows member 2 is not particularly limited. The first bellows member 2 expands and contracts in the axial direction (Z direction). As shown in FIG. 2, the first bellows member 2 has an annular shape when viewed in the axial direction (Z direction).

As shown in FIG. 3, the first bellows member 2 includes an outer diameter portion 71 and an inner diameter portion 72. In FIG. 3, the outer diameter portion 71 and the inner diameter portion 72 of the first bellows member 2 are indicated by broken lines. The outer diameter portion 71 and the inner diameter portion 72 of the first bellows member 2 are formed in a substantially linear shape along the axial direction (Z direction) of the first bellows member 2. The outer diameter D1 and the inner diameter D2 of the first bellows member 2 are substantially constant along the axial direction (Z direction) of the first bellows member 2.

As shown in FIG. 4, the first bellows member 2 includes a plurality of outer protruding portions 41 and a plurality of inner protruding portions 42. The plurality of outer protruding portions 41 correspond to the outer diameter portion 71 of the first bellows member 2. The plurality of inner protruding portions 42 correspond to the inner diameter portion 72 of the first bellows member 2. The outer protruding portion 41 projects to the outside of the first bellows member 2. The inner protruding portion 42 protrudes inside the first bellows member 2. The first bellows member 2 includes a plurality of plate members 21. The plate member 21 has an annular shape when viewed in the axial direction (Z direction) of the first bellows member 2 (see FIG. 2 ). The first bellows member 2 is configured by combining a plurality of plate members 21. The plate members 21 adjacent to each other in the axial direction (Z direction) of the first bellows member 2 are joined by, for example, welding or diffusion joining. At the outer protruding portion 41 of the first bellows member 2, the outer peripheral portions 61 of the plate members 21 adjacent to each other in the axial direction (Z direction) are joined. At the inner protruding portion 42 of the first bellows member 2, the inner peripheral portions 62 of the plate members 21 adjacent to each other in the axial direction (Z direction) are joined.

As shown in FIG. 1, the upper support member 11 arranged on the upper side of the first bellows member 2 is a plate-shaped member and is fixed in a state of being in close contact with the upper end portion of the first bellows member 2. Further, the lower support member 12 arranged below the first bellows member 2 is a plate-shaped member and is fixed in a state of being in close contact with the lower end portion of the first bellows member 2. The upper support member 11 and the lower support member 12 seal the sealed space 51. A closed space 51 is formed between the upper support member 11 and the lower support member 12. A compressible fluid is enclosed in the closed space 51. The compressible fluid sealed in the closed space 51 is a gas such as air or gas. It may also be used in combination with an incompressible fluid such as water or oil.

As shown in FIGS. 1 and 2, the peripheral member 90 of the spring structure 1 is arranged around the first bellows member 2 and surrounds the first bellows member 2. A peripheral member 90 is arranged outside the first bellows member 2 in the radial direction of the first bellows member 2. An intermediate space 95 is formed between the peripheral member 90 and the first bellows member 2. The intermediate space 95 is a space existing outside the first bellows member 2 and inside the peripheral member 90. The intermediate space 95 is formed between the upper support member 11 and the lower support member 12. A compressive fluid may be enclosed in the intermediate space 95. The compressive fluid sealed in the intermediate space 95 is a gas such as air or gas. The pressure in the intermediate space 95 is lower than the pressure in the closed space 51.

The surrounding member 90 includes a metal upper member 91 and a metal lower member 92. Both the upper member 91 and the lower member 92 are rigid bodies. The upper member 91 and the lower member 92 are members that are less likely to be deformed than the plate member 21 of the first bellows member 2.

The lower member 92 is arranged around the first bellows member 2 and surrounds the first bellows member 2. The lower end of the lower member 92 is fixed to the lower support member 12. The lower member 92 extends along the axial direction (Z direction) of the first bellows member 2. The lower member 92 has an annular shape when viewed in the axial direction (Z direction) of the first bellows member 2 (see FIG. 2 ). The lower member 92 extends along the circumferential direction of the first bellows member 2. As shown in FIG. 5, the surface of the lower member 92 is coated with a resin layer 99. The resin layer 99 coating the lower member 92 is, for example, a silicone resin or a fluororesin.

As shown in FIGS. 1 and 2, the upper member 91 is arranged around the lower member 92 and the first bellows member 2, and surrounds the lower member 92 and the first bellows member 2. The upper end of the upper member 91 is fixed to the upper support member 11. The upper member 91 extends along the axial direction (Z direction) of the first bellows member 2. The upper member 91 has an annular shape when viewed in the axial direction (Z direction) of the first bellows member 2 (see FIG. 2 ). The upper member 91 extends along the circumferential direction of the first bellows member 2.

The lower member 92 and the upper member 91 slide in the vertical direction as the first bellows member 2 expands and contracts in the axial direction (Z direction). The lower member 92 and the upper member 91 relatively move along the axial direction (Z direction) of the first bellows member 2. In the radial direction of the peripheral member 90, a gap 94 is formed between the upper member 91 and the lower member 92. The size of the gap 94 is large enough to prevent the fluid from flowing out between the upper member 91 and the lower member 92. Therefore, the fluid is suppressed from flowing out of the intermediate space 95 to the outside of the peripheral member 90.

In the spring structure 1 having the above configuration, as shown by the arrow in FIG. 1, the load P acts on the spring structure 1 including the first bellows member 2 via the upper support member 11 and the lower support member 12. At this time, the load P can be supported by the pressure of the compressive fluid sealed in the closed space 51 inside the first bellows member 2. Further, the spring structure 1 includes a peripheral member 90 arranged around the first bellows member 2. The surrounding member 90 is provided with a structure that suppresses the outflow of fluid from the intermediate space 95 outside the first bellows member 2 and inside the surrounding member 90 to the outside of the surrounding member 90. According to this configuration, even if the first bellows member 2 ruptures due to the increase in the pressure in the closed space 51, the compressible fluid sealed in the closed space 51 is prevented from flowing out of the surrounding member 90. can do. Therefore, it is possible to prevent the pressure in the closed space 51 from rapidly decreasing, and it is possible to prevent the ability of the spring structure 1 to support the load from rapidly decreasing. Moreover, even if the first bellows member 2 bursts, the burst noise can be suppressed. Further, it is possible to prevent the fragments of the first bellows member 2 from scattering around.

Further, in the spring structure 1 described above, the peripheral member 90 includes the rigid body members (the lower member 92 and the upper member 91) extending along the axial direction (Z direction) of the first bellows member 2. According to this configuration, since the rigid member is present outside the first bellows member 2, it is possible to prevent the first bellows member 2 from expanding outward (that is, buckling).

Further, in the spring structure 1 described above, the surface of the lower member 92 on the first bellows member 2 side is coated with the resin layer 99. With this configuration, it is possible to reduce the frictional resistance between the first bellows member 2 and the lower member 92 when the first bellows member 2 expands and contracts.

Although one embodiment has been described above, the specific mode is not limited to the above embodiment. In the following description, the same components as those in the above description will be designated by the same reference numerals and the description thereof will be omitted.

(Second embodiment)
In the second embodiment, as shown in FIG. 6, the lower member 92 of the peripheral member 90 may include a base portion 921, a protruding portion 922, and a step portion 923. The lower end of the base 921 is fixed to the lower support member 12. The protrusion 922 protrudes upward from the upper end of the base 921. A step 923 is formed on the upper end of the base 921.

Further, in the second embodiment, the inner surface of the lower member 92 (on the bellows member 2 side) is coated with the resin layer 99. The outer surface of the lower member 92 (on the upper member 91 side) is not coated with the resin layer 99. Further, the inner surface (lower member 92) of the upper member 91 is coated with the resin layer 99.

Further, in the second embodiment, the seal member 93 may be arranged in the gap 94 between the upper member 91 and the lower member 92 of the peripheral member 90. The seal member 93 is arranged on the step portion 923 of the lower member 92. The seal member 93 may be press-fitted into the lower member 92. The sealing member 93 seals the gap 94 to suppress the outflow of gas from the intermediate space 95 to the outside of the surrounding member 90. The seal member 93 has a lip seal structure. As shown in FIG. 7, the seal member 93 includes a pair of lip portions 931 and 931. One of the pair of lip portions 931 is in contact with the resin layer 99 coating the inner surface of the upper member 91. The other of the pair of lip portions 931 is in contact with the outer surface of the lower member 92.

According to this configuration, the gap 94 between the upper member 91 and the lower member 92 is sealed by the seal member 93, so that even if the first bellows member 2 ruptures, the compression that is enclosed in the closed space 51 is suppressed. It is possible to further suppress the sexual fluid from flowing out of the surrounding member 90.

(Third embodiment)
In the third embodiment, as shown in FIG. 8, the spring structure 1 may include the pressure sensor 80. The pressure sensor 80 is fixed to the upper member 91 of the surrounding member 90. The pressure sensor 80 detects the pressure in the intermediate space 95. The pressure sensor 80 is connected to the control device 100, and information on the pressure detected by the pressure sensor 80 is transmitted to the control device 100.

The control device 100 determines whether or not the spring structure 1 is out of order, based on the pressure detected by the pressure sensor 80. For example, when the first bellows member 2 ruptures and the compressive fluid enclosed in the closed space 51 flows into the intermediate space 95, the pressure in the intermediate space 95 increases. The controller 100 can determine that the spring structure 1 has failed when the pressure in the intermediate space 95 is higher than a predetermined threshold value. Further, even if the pressure sensor for detecting the pressure in the closed space 51 is not provided, by providing the pressure sensor 80 for detecting the pressure in the intermediate space 95, it is possible to prevent the compressible fluid from flowing out from the closed space 51. Can be detected. Further, since the pressure sensor 80 is fixed to the upper member 91 and it is not necessary to directly detect the pressure of the closed space 51 inside the first bellows member 2, the airtightness of the closed space 51 can be maintained. Further, since the pressure in the intermediate space 95 is lower than the pressure in the closed space 51, the pressure sensor 80 can be configured for low pressure, and the cost can be reduced.

(Fourth embodiment)
In the fourth embodiment, as shown in FIG. 9, the spring structure 1 includes the second bellows member 102. The second bellows member 102 corresponds to the peripheral member 90. The second bellows member 102 is arranged around the first bellows member 2 and surrounds the first bellows member 2. The second bellows member 102 is arranged outside the first bellows member 2 in the radial direction of the first bellows member 2. An intermediate space 95 is formed between the second bellows member 102 and the first bellows member 2. The structure of the second bellows member 102 is the same as the structure of the first bellows member 2 described above except that it is arranged around the first bellows member 2, and thus detailed description thereof is omitted.

Further, in the fourth embodiment, the communication part 115 is formed in the upper support member 11. One end of the communication portion 115 communicates with the intermediate space 95. The pressure in the communication portion 115 is the same as the pressure in the intermediate space 95. The pressure sensor 80 is inserted into the other end of the communication portion 115. The pressure sensor 80 detects the pressure in the intermediate space 95 by detecting the pressure in the communication section 115. The pressure sensor 80 is fixed to the upper support member 11.

According to this configuration, since the second bellows member 102 is arranged around the first bellows member 2, even if the first bellows member 2 ruptures, the compressive fluid sealed in the closed space 51 is Outflow to the outside of the second bellows member 102 can be suppressed. Therefore, it is possible to prevent the pressure in the closed space 51 from rapidly decreasing, and it is possible to prevent the ability of the spring structure 1 to support the load from rapidly decreasing. Further, even if the pressure sensor for detecting the pressure of the closed space 51 is not provided, by providing the pressure sensor 80 for detecting the pressure of the intermediate space 95 via the communication portion 115, the compressive fluid is closed. It is possible to detect the outflow from 51. Moreover, since it is not necessary to directly detect the pressure of the closed space 51 inside the first bellows member 2, the airtightness of the closed space 51 can be maintained. Further, since the pressure in the intermediate space 95 is lower than the pressure in the closed space 51, the pressure sensor 80 can be configured for low pressure, and the cost can be reduced.

(Other embodiments)
(1) In another embodiment, the outer surface of the lower member 92 may also be coated with resin. In another embodiment, the surface of the upper member 91 may be coated with resin.

(2) In another embodiment, the pressure of the closed space 51 may be adjusted by adjusting the amount of the compressive fluid sealed in the closed space 51. Further, the pressure in the intermediate space 95 may be adjusted by adjusting the amount of the compressive fluid sealed in the intermediate space 95. By adjusting the pressure of the closed space 51 and the pressure of the intermediate space 95, the pressure difference between the inside and the outside of the first bellows member 2 can be adjusted.

(3) In the above embodiment, the upper member 91 is arranged outside the lower member 92, but in other embodiments, conversely, the lower member 92 is arranged outside the upper member 91. It may have been done.

Specific examples of the present invention have been described above in detail, but these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and changes of the specific examples illustrated above. The technical elements described in the present specification or the drawings exert technical utility alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technique illustrated in the present specification or the drawings can simultaneously achieve a plurality of purposes, and achieving the one purpose among them has technical utility.

1: spring structure, 2: first bellows member, 11: upper side supporting member, 12: lower side supporting member, 21: plate member, 41: outer protruding portion, 42: inner protruding portion, 51: closed space, 61: outer periphery Part, 62: inner peripheral part, 71: outer diameter part, 72: inner diameter part, 80: pressure sensor, 90: peripheral member, 91: upper member, 92: lower member, 93: seal member, 94: gap, 95 : Intermediate space, 99: Resin layer, 100: Control device, 102: Second bellows member, 115: Communication part, 921: Base part, 922: Projection part, 923: Step part, 931: Lip part

Claims (5)

A first metal bellows member,
A peripheral member that is disposed around the first bellows member and that surrounds the first bellows member,
A compressible fluid is enclosed in a closed space inside the first bellows member,
The said surrounding member is a spring structure provided with the structure which suppresses flowing out of the fluid to the outer side of the said surrounding member from the intermediate space outside the said 1st bellows member and inside the said surrounding member. The spring structure according to claim 1, wherein
The spring structure further comprising a pressure sensor for detecting the pressure in the intermediate space. The spring structure according to claim 1 or 2, wherein
The said surrounding member is a spring structure provided with the rigid member extended along the axial direction of the said 1st bellows member. The spring structure according to claim 3,
A spring structure in which a surface of the rigid member on the first bellows member side is coated with a resin layer. The spring structure according to claim 1 or 2, wherein
The spring structure, wherein the peripheral member is a metal second bellows member that is arranged around the first bellows member and surrounds the first bellows member.

Images