JPH08121598A - Sealed part sealing structure - Google Patents

Abstract

PURPOSE: To prevent marring of a sealed part and to maintain a sealing function for a long period of time by storing pressure rings on upper and lower end sides of a seal ring to be stored in a ring storage part and forming a ring straightening surface making contact with a blocking side of the storage part and one end side of the seal ring. CONSTITUTION: A metallic receiver ring 6, an expansion graphite made seal ring 7 and a metallic presser ring 8 are sequentially built in a ring storage part 5 formed on a facing peripheral surface of a valve chest 2 and a valve cover 4, and a tapered surface 5a of the ring storage part 5 and tapered surfaces 6a, 7a of the receiver ring 6 and the seal ring 7 are made contact with each other. Thereafter, a metallic split ring 7 is fit in a ring fitting groove 2a on an upper end side inner peripheral surface of the valve chest 2 and fixed. Consequently, as each of the tapered surfaces 6a, 7a of the receiver ring 6 and the seal ring 7 is made contact with each other, a contact side end part of the seal ring is straightened in the radial direction by compressive deformation, made pressure contact with the inner peripheral surface of the valve chest 2 and the outer peripheral surface of the valve cover 4 and sealed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a self-tightening type, which is usually called Bridgman type, used for sealing parts such as valves and pumps, or sealing parts such as filters and heaters. The present invention relates to a sealing structure for a sealing part.

[0002]

2. Description of the Related Art Conventionally, as a sealing structure used in a sealing portion of a valve as in the above example, for example, as shown in FIGS. 7 and 8, an open side of a valve box 22 constituting a flow control valve 21. The valve closing plate 23 fixed to the upper end is opened, and a metal seal ring 26 formed in a wedge-shaped cross section and a metal formed in a square cross section are formed in a ring storage part 25 formed on the outer peripheral surface of the valve lid 24 on the lower end side. After inserting the spacer ring 27 made of metal, a split ring 28 made of metal is fitted and fixed to the inner peripheral surface of the upper end side of the valve box 22.

Next, after fitting the valve closing plate 23 to the upper end of the valve box 22 on the open side, the valve box 22 and the valve closing plate 23 are tightened and fixed with the respective tightening bolts 29 ... After tightening the respective tightening bolts 30 ... Installed, a fluid pressure end force is applied to the lower portion of the valve lid 24 to form a taper surface 25a formed on the closed side inner peripheral portion of the ring housing portion 25 and the lower end of the seal ring 26. By contacting the tapered surface 26a formed on the inner peripheral side with each other,
There is a seal structure in which the opposite end of the seal ring 26 is plastically deformed in the radial direction, and the seal ring 26 is pressed against the inner peripheral surface of the valve box 22 and the inner peripheral surface of the ring housing portion 25 to seal.

[0004]

However, in the above-mentioned sealing structure, the ring 26 is axially pressed by the tightening force of each tightening bolt 30, and the seal ring 26 is plastically deformed in the radial direction by the end force of fluid pressure. Then, the seal ring 26 is pressed against the inner peripheral surface of the valve box 22 and the outer peripheral surface of the valve lid 24 for sealing. However, since the valve box 22 and the seal ring 26 are made of a metal material, the seal ring 26 is formed. Has a problem that when it is plastically deformed, a scratch is generated on the inner peripheral surface of the valve box 22.

In addition, in order to remove the scratches on the inner peripheral surface of the valve box 22, it is necessary to correct the buildup or cutting of the scratched portion, but the valve box 22 and the seal ring 26 are fitted with each other by a clearance fit tolerance. Since they are fitted together, high processing accuracy and processing technology are required, and there is also a problem that the processing cost at the time of correction becomes expensive.

Further, when the scratches on the inner peripheral surface of the valve box 22 are removed by cutting, the inner diameter of the valve box 22 becomes larger by the amount of the cutting, and the gap between the valve box 22 and the seal ring 26 becomes larger than the size before correction. Valve box 2 after correction
The seal ring 26 and the valve lid 24, which are of such a size that they are fitted in the gap 2, must be newly manufactured, which causes a problem that the manufacturing cost increases.

In view of the above problems, the present invention can prevent the seal portion from being damaged by compressing and deforming the seal ring made of expanded graphite stored in the ring storage portion of the sealing portion in the radial direction to seal the seal portion. At the same time, it is an object of the present invention to provide a sealing portion sealing structure capable of maintaining a sealing function for a long period of time without newly manufacturing a valve lid.

[0008]

According to the first aspect of the present invention,
An expanded graphite seal ring is accommodated in the ring accommodating portion formed in the sealing portion, the pressure rings are accommodated at the upper end side and the lower end side of the seal ring, and the closed side of the ring accommodating portion and the seal are The sealing structure is characterized in that each ring correction surface is formed so as to be in contact with one end side of the ring.

According to a second aspect of the present invention, in addition to the structure of the first aspect, each of the taper surfaces for contacting the ring correction surface with the closed side of the ring accommodating portion and one end side of the seal ring are in contact with each other. It is characterized in that it has a sealing portion sealing structure formed by forming.

According to a third aspect of the present invention, in addition to the structure of the first aspect, the rounded surfaces that contact the ring correction surface with the closed side of the ring accommodating portion and the one end side of the seal ring are in contact with each other. It is characterized in that it has a sealing portion sealing structure formed by forming.

According to a fourth aspect of the present invention, in addition to the structure according to the first aspect, the thickness of the pressure ring accommodated on the closed side of the ring accommodating portion is calculated from the ring correction surface formed in the ring accommodating portion. It is also characterized by having a thinner sealing structure.

According to a fifth aspect of the present invention, in addition to the structure of the first aspect, the outer peripheral surface of each pressure ring housed in the ring housing portion and the inner peripheral surface of the outer member are fitted with a clearance. A sealing portion seal structure in which the inner peripheral surface of the pressure ring housed on the open side of the ring housing portion and the outer peripheral surface of the ring housing portion are fitted and fixed by a gap fitting tolerance. Is characterized by.

[0013]

In the sealing portion sealing structure according to claim 1, after the sealing ring made of expanded graphite is stored in the ring storage portion formed in the sealing portion, the sealing ring stored in the ring storage portion is applied to each pressure ring. By pressurizing the ring storage portion and the ring correction surfaces formed on the seal ring against each other, the contact side end portion of the seal ring is radially compressed and deformed, and the outer peripheral surface of the inner member and the outer member The inner peripheral surface and the inner and outer peripheral surfaces of the seal ring are pressed against each other and sealed.

In the sealing portion sealing structure according to a second aspect of the invention, in addition to the action of the first aspect, the tapered surfaces formed on the ring housing portion and the seal ring are in contact with each other,
The opposite end of the seal ring is compressed and deformed in the radial direction, and the inner and outer peripheral surfaces of the seal ring are pressed against the inner member and the outer member to seal the inner member and the outer member, and the stress concentration generated in the ring housing is avoided.

According to the sealing structure of the third aspect, in addition to the operation of the first aspect, the rounded surfaces formed on the ring housing and the seal ring are in contact with each other,
The opposite end of the seal ring is compressed and deformed in the radial direction, and the inner and outer peripheral surfaces of the seal ring are pressed against the inner member and the outer member to seal the inner member and the outer member, and the stress concentration generated in the ring housing is avoided.

In the sealing portion sealing structure according to claim 4, in addition to the operation according to claim 1, a ring in which the thickness of the pressure ring accommodated on the closed side of the ring accommodating portion is formed in the ring accommodating portion. By making it thinner than the straightening surface, each ring straightening surface formed on the ring housing portion and the seal ring is surely brought into contact with each other, and the compression deformation of the seal ring is guided by the pressure ring, so that the inner member and the outer member are The seal ring is prevented from being caught in the clearance portion.

In the sealing structure according to the fifth aspect of the invention, in addition to the action of the first aspect, a gap is formed between the outer peripheral surface of each pressure ring housed in the ring housing and the inner peripheral surface of the outer member. The inner member and the outer side are fitted and fixed by the fitting tolerance, and the inner peripheral surface of the pressure ring housed on the open side of the ring housing and the outer peripheral surface of the ring housing are fitted and fixed by the gap fitting tolerance. The seal ring is prevented from being caught in the gap portion of the member.

[0018]

According to the present invention, since the expandable graphite seal ring housed in the ring housing portion of the sealing portion is compressed and deformed in the radial direction to seal, the metal members are separated from each other as in the conventional example. The sealing property is superior to that of the pressure-contacting seal structure, and the other member such as the inner member or the outer member is not damaged, and the sealing function can be maintained for a long time. Moreover, since the seal ring is compressed and deformed along the pressure ring, it is possible to reliably prevent the seal ring from being caught in the gap between the inner member and the outer member, and to prevent the sealing function from being deteriorated due to the engagement.

Even if the inner peripheral surface of the outer member is scratched,
Compared to the seal structure of the conventional example, the damage is shallower, the amount of buildup and cutting at the time of modification is less, and each ring before modification can be reused, so there is no need to manufacture a new seal ring and it is economical. Yes, or only the rings other than the seal ring need be manufactured, and the cost can be reduced.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The drawings show the sealing structure of the first embodiment used in a flow rate control valve as an example of the sealing part. In FIGS. 1 and 2, the sealing structure of the present invention is shown. The provided flow rate control valve 1 is configured such that the valve closing plate 3 fitted and fixed to the upper end of the opening side of the valve box 2 is once opened to open the valve box 2
A metal receiving ring 6, a sealing ring 7 made of expanded graphite, and a metal pressing ring 8 are sequentially assembled in a ring housing portion 5 formed by the opposing circumferential surfaces of the valve lid 4 and the ring housing portion 5. The tapered surface 5a formed on the above and the tapered surfaces 6a and 7a formed on the receiving ring 6 and the seal ring 7 are in contact with each other. After that, the metal ring split ring 9 is fitted and fixed in the ring fitting groove 2a formed in the inner peripheral surface of the valve box 2 on the upper end side.

As shown in FIG. 3, the fitting structure of the rings 6, 7 and 8 described above has a clearance fitting tolerance between the inner peripheral surface of the valve box 2 and the outer peripheral surfaces of the receiving ring 6 and the pressing ring 8. The ring storage part 5 which is fitted and fixed by the
The outer peripheral surface of the valve ring 2 and the inner peripheral surface of the presser ring 8 are fitted and fixed by a gap fitting tolerance, and the inner peripheral surface of the valve box 2 and the outer peripheral surface of the ring housing portion 5 are opposed to the inner and outer peripheral surfaces of the seal ring 7. They are in close contact with each other.

In addition, the taper surface 5a formed on the closed side inner peripheral portion of the ring housing portion 5, the taper surface 6a formed on the one end side inner peripheral portion of the receiving ring 6, and the one end side inner peripheral portion of the seal ring 7. The formed tapered surface 7a is chamfered at the same angle, and each tapered surface 5a, 6a, 7a is formed with an inclination angle widened with respect to the vertical direction.

In addition, the thickness t of the receiving ring 6 is made smaller than the height to of the tapered surface 5a formed on the closed-side inner peripheral portion of the ring storage portion 5 so that the mutual relationship becomes to> t. are doing.

Assuming that the illustrated embodiment is configured as described above, a method of assembling the sealing portion sealing structure used in the flow rate adjusting valve 1 will be described below. First, as shown in FIGS. 1 and 2, the valve closing plate 3 fitted and fixed to the upper end of the valve box 2 on the open side is temporarily opened to form a ring housing formed between the valve box 2 and the valve lid 4. The receiving ring 6, the seal ring 7, and the pressing ring 8 are sequentially assembled in the portion 5, and the tapered surface 5a formed in the ring housing portion 5 and the tapered surfaces 6a, 7a formed in the receiving ring 6 and the seal ring 7 are formed. Touch each other. After that, the split ring 9 is fitted and fixed in the ring fitting groove 2a formed in the inner peripheral surface of the upper end side of the valve box 2.

Next, after the valve closing plate 3 is fitted and fixed to the upper end of the valve box 2 on the open side, the plurality of tightening bolts 10 ... Inserted in the outer peripheral edge of the valve closing plate 3 are attached to the valve box 2.
Tighten and fix it by screwing on the upper end of the open side. A plurality of tightening bolts 11 inserted into the inner peripheral edge of the valve closing plate 3
Is screwed to the outer peripheral portion of the valve lid 4 on the lower end side to be fixed by tightening. That is, the tightening bolts 11 are rotated in the tightening direction to relatively move the valve box 2 and the valve lid 4 in a direction in which the rings 6, 7 and 8 are pressed against the axial direction, and the tightening is performed. By the tightening force of the bolts 11, ...
As shown in FIG. 3, the taper surface 5a formed on the ring housing portion 5, the receiving ring 6, and the seal ring 7 are pressed against each other.
By abutting the respective tapered surfaces 6a and 7a formed on the opposite side, the contact side end of the seal ring 7 is corrected in the radial direction by compression deformation, and the inner peripheral surface of the valve box 2 and the outer peripheral surface of the valve lid 4 are corrected. The seal ring 7 is pressed against and sealed.

In addition, the deformation direction of the seal ring 7 is guided by the receiving ring 6 to reliably prevent the seal ring 7 from being caught in the gap between the valve box 2 and the valve lid 4.

As a comparative example of the above-mentioned tapered seal ring 7, for example, as shown in FIG.
The height of the tapered surface 5a formed on
When the thickness t of the seal ring 7 is reduced, the tapered surface 5a formed on the ring housing portion 5 and the tapered surface 7a formed on the seal ring 7
Contact each other, and the end portion of the seal ring 7 on the contact side is compressed and deformed in the radial direction. Therefore, the seal ring 7 is positively pressed against the inner peripheral surface of the valve box 2 and the outer peripheral surface of the valve lid 4. can do.

On the other hand, as shown in FIG.
The height of the tapered surface 5a formed on
If the thickness t is increased, the receiving ring 6 and the pressing ring 8
Since the seal ring 7 interposed between and is compressed and deformed only in the axial direction, the deformation rate in the radial direction is smaller than that of the seal structure of the present invention, and the inner peripheral surface of the valve box 2 and the outer peripheral surface of the valve lid 4 are. Since the pressure contact force with respect to is weak, the sealing structure of the present invention is superior in the sealing function.

As described above, the expanded graphite seal ring 7 stored in the ring storage portion 5 is radially corrected by compression deformation, and the seal ring 7 is formed on the inner peripheral surface of the valve box 2 and the outer peripheral surface of the valve lid 4. Since it is pressure-contacted and sealed, it has a better sealing property than the conventional seal structure in which metal members are pressure-contacted with each other, and the other parts such as the valve box 2 and the valve lid 4 are damaged. It is possible to maintain the sealing function for a long time without wearing. Moreover, since the seal ring 7 is compressed and deformed along the receiving ring 6, it is possible to reliably prevent the seal ring 7 from being caught in the gap portion between the valve box 2 and the valve lid 4, and the sealing function is deteriorated by the engagement. Can be prevented.

Even if the inner peripheral surface of the valve box 2 is damaged, the damage is shallower than that of the conventional seal structure, and the amount of build-up and cutting at the time of modification is small. Since 6, 7, 8 can be reused, a new seal ring 7
It is economical because there is no need to manufacture the above, or only the other rings 6 and 8 except the seal ring 7 need to be manufactured, and the cost can be reduced.

4 and 5, the rounded surface 5b formed on the closed inner peripheral portion of the ring accommodating portion 5, the rounded surfaces 6b formed on the inner peripheral portions of the receiving ring 6 and the seal ring 7 on one end side,
7b shows a sealing portion sealing structure of a second embodiment in which the sealing member 7b and the sealing member 7b are sealed against each other. The structure has a rounded surface 5b formed on the closed side inner peripheral portion of the ring housing portion 5 and one end side of the receiving ring 6. The rounded surface 6b formed on the inner peripheral portion and the rounded surface 7b formed on the inner peripheral portion on one end side of the seal ring 7 are processed to have the same radius of curvature, and the rounded surfaces 5b, 6b, 7b are arranged in the vertical direction. The radius is gradually increased to form a rounded shape.

In addition, the thickness t of the receiving ring 6 is made smaller than the height to of the rounded surface 5b formed on the closed-side inner peripheral portion of the ring housing portion 5 so that the mutual relationship becomes to> t. are doing.

That is, the receiving ring 6, the seal ring 7, and the holding ring 8 are sequentially assembled in the ring storage portion 5 formed between the valve box 2 and the valve lid 4, and the ring storage portion 5 is formed.
The rounded surface 5b formed on the above and the rounded surfaces 6b and 7b formed on the receiving ring 6 and the seal ring 7 are in contact with each other. After this, the ring fitting groove 2 formed in the valve box 2
The split ring 9 is fitted in and fixed to a.

Next, after the valve closing plate 3 is fitted and fixed to the upper end of the valve box 2 on the open side, the valve box 2 and the valve closing plate 3 are tightened and fixed by the tightening bolts 10 ... The valve closing plate 3 is tightened and fixed by the tightening bolts 11 ... That is, the tightening bolts 11 ... Are rotated in the tightening direction to relatively move the valve box 2 and the valve lid 4 in the direction in which the rings 6, 7 and 8 are pressed against each other, and the tightening bolts 11 are tightened. By force, the rings 6, 7, and 8 stored in the ring storage portion 5 are divided into rings 9
Rounded surface 5b formed on the ring storage portion 5 by pressing with
And the rounded surfaces 6b, 7b formed on the inner peripheral portions of the receiving ring 6 and the seal ring 7 on one end side are brought into contact with each other, so that the contact side end portion of the seal ring 7 is moved in the same manner as in the first embodiment. It is corrected in the radial direction by compressive deformation, and the seal ring 7 is pressed against the inner peripheral surface of the valve box 2 and the outer peripheral surface of the valve lid 4 to seal them.

Further, since the deformation direction of the seal ring 7 is guided by the receiving ring 6, the seal ring 7 is surely prevented from being caught in the gap between the valve box 2 and the valve lid 4. The same effect as that of the first embodiment can be obtained.

In the correspondence between the configuration of the present invention and the above-described embodiment, the sealing portion of the present invention corresponds to the flow rate control valve 1 of the embodiment, and hereinafter, the outer member also corresponds to the valve box 2. The inner member corresponds to the valve lid 4, the pressure ring corresponds to the receiving ring 6 and the pressing ring 8, and the ring correction surface is each tapered surface 5a, 6a, 7a and each rounded surface 5b. , 6b, 7b, the present invention is not limited to the configuration of the above-described embodiment.

In the above-described first and second embodiments, the seal structure used in the sealing portion of the flow rate control valve 1 has been described. However, for example, it may be used in the sealing portion of a filter or a heater. Of course, the application is not limited to only the flow rate control valve 1 shown in the embodiment.

The seal ring 7 may be made of expanded graphite alone, and the upper and lower surfaces and corners thereof may be reinforced with a mesh or a thin metal plate.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional side view showing a sealing structure of a sealing portion according to a first embodiment used in a flow rate control valve.

FIG. 2 is a vertical cross-sectional side view showing an assembled state of each ring.

FIG. 3 is a vertical cross-sectional side view showing a contact portion of a tapered seal ring.

FIG. 4 is a vertical cross-sectional side view showing a sealing portion seal structure of the second embodiment and an assembled state of each ring.

FIG. 5 is a vertical cross-sectional side view showing a contact portion of a rounded seal ring.

FIG. 6 is a vertical cross-sectional side view showing an example in which the receiving ring is formed thicker than the tapered portion.

FIG. 7 is a vertical cross-sectional side view showing a conventional seal structure used in a flow rate control valve.

FIG. 8 is a vertical cross-sectional side view showing an assembled state of each ring.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Flow control valve 2 ... Valve box 3 ... Valve closing plate 4 ... Valve lid 5 ... Ring storage part 6 ... Receiving ring 7 ... Seal ring 5a, 6a, 7a ... Tapered surface 5b, 6b, 7b ... Earl surface 8 ... Presser foot Ring 9 ... Split ring

Claims (5)

[Claims] 1. A sealing method in which a ring accommodating portion is formed between opposed surfaces of an inner member and an outer member constituting a sealing portion, and a seal ring accommodated in the ring accommodating portion is pressurized by a pressure ring to seal the seal ring. Partial seal structure, in which a ring containing part made of expanded graphite is housed in the ring containing part formed in the sealing part, and each pressurizing ring is housed on the upper end side and the lower end side of the seal ring, and the ring containing part is also housed. A sealing part seal structure in which ring correction surfaces are formed so as to be in contact with each other on the closed side of the part and one end side of the seal ring. 2. The sealing structure for a sealing portion according to claim 1, wherein the ring correction surface is formed by forming tapered surfaces facing each other on the closed side of the ring housing portion and one end side of the seal ring. 3. The sealing structure according to claim 1, wherein the ring straightening surface is formed by forming rounded surfaces that are in contact with each other on the closed side of the ring housing and one end side of the seal ring. 4. The sealing portion sealing structure according to claim 1, wherein the thickness of the pressure ring housed on the closed side of the ring housing portion is smaller than the thickness of the ring correction surface formed on the ring housing portion. 5. An outer peripheral surface of each pressure ring accommodated in the ring accommodating portion and an inner peripheral surface of the outer member are fitted and fixed to each other by a gap fitting tolerance and accommodated on the open side of the ring accommodating portion. 2. The sealing portion sealing structure according to claim 1, wherein the inner peripheral surface of the pressure ring and the outer peripheral surface of the ring housing portion are fitted and fixed by a clearance fit tolerance.