JPH10281299A - Mechanical seal device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To certainly hold a seal clearance between a rotary ring and a static ring along an overall area from an inner periphery to an outer periphery and prevent occurrence of metallic contact by forming a large number of groove parts along the circumferential direction in the neighborhood of an outlet on the low pressure region side of the seal clearance and land parts between each of the groove parts. SOLUTION: Spiral groove parts are engraved and provided on a side surface facing against a seal clearance 150 of a rotary ring 1 and constitute a dynamic pressure bearing. Inside groove parts are engraved and provided with equal intervals in the circumferential direction on the same side surface of a static ring 2, and these inside groove parts are formed roughly in a T letter shape on a portion to the outlet to the side of a low pressure region B of the seal clearance 150 (that is, a portion to the inner periphery), and they constitute a static pressure bearing with the land parts between each of these groove parts. These dynamic pressure bearing and the inside groove parts and floating force by the static pressure bearing by the land parts show a characteristic to increase (decrease) the floating force when the seal clearance 150 decreases (increases). Consequently, under a condition where a pressure ratio of a high pressure region A and a low pressure region B is high, the seal clearance 150 can be held constant along the overall region of the inner and outer peripheries.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a non-contact type mechanical seal device applied as a shaft sealing device for a rotary machine such as a compressor or a pump.

[0002]

2. Description of the Related Art FIGS. 7 to 9 show a conventional example of a non-contact type mechanical seal device used as a shaft sealing device for a rotary shaft portion of a gas compressor. FIG. Longitudinal sectional view, FIG. 8 is a front view seen from the seal clearance side of the rotating ring,
FIG. 9 is an enlarged view of a portion Z in FIG.

In FIGS. 7 to 9, reference numeral 153 denotes a main body of the compressor, 154 denotes an internal housing, and 103 denotes a rotary shaft driven by a drive source (not shown) such as an electric motor. Reference numeral 101 denotes a sleeve fixedly inserted on the outer periphery of the rotating shaft 103, and rotates integrally with the rotating shaft 103. Reference numeral 1 denotes a rotary ring fixedly inserted around the outer periphery of the cylindrical portion of the sleeve 101, and rotates integrally with the sleeve 101 and the rotary shaft 103.
Reference numeral 4 denotes a casing fixedly inserted into the inner periphery of the main body 153, which is fixed to the inner housing 154 by bolts.

[0004] Reference numeral 3 denotes a retainer provided inside the casing 4. Reference numeral 2 denotes a stationary ring, and the rotating shaft 103
In the axial direction, the retainer 3 and the rotary ring 1 are provided so as not to rotate between the retainer 3 and the rotary ring 1, and are finely movable in the axial direction together with the retainer 3 by a compression spring 4C described later. The retainer 3 is fitted to the inner periphery of the casing 4 with an appropriate fit to the inner periphery of the casing 4 so that the retainer 3 can be finely moved in the axial direction with respect to the casing 4. A plurality of compression springs 4C are disposed in the inner circumferential direction between the side surface of the retainer 3 on the casing 4 side and the side surface of the casing 4 opposed thereto, and the retainer 3 and the stationary ring 2 are connected to the rotating ring. Pressing to one side.

A is a high-pressure area B communicating with a high-pressure gas passage, a low-pressure area communicating with the atmosphere, and a seal between the high-pressure area A and the low-pressure area B is provided by the following means. The shaft is sealed. That is, 3A is a back O-ring provided at a contact portion between the stationary ring 2 and the retainer 3, 4A is a secondary seal provided in a groove 4B of a casing of a sliding portion between the retainer 3 and the casing 4, and 102 is a secondary seal. O is provided at a contact portion of the sleeve 101 with the rotating ring 1.
It is a ring. This compressor prevents gas from leaking from the high-pressure area A to the low-pressure area B by means of the three sealing portions and a shaft sealing means in a seal clearance 150 between the rotating ring 1 and the stationary ring 2 which will be described later. ing.

[0006] A minute clearance, that is, a seal clearance 150 is formed between the side surface of the rotary ring 1 and the side surface of the stationary ring 2 opposed thereto, and the seal clearance 150 is formed between the high pressure region A and the low pressure region B. Between the pressure boundary.
Then, while the gas passes through the seal clearance 150 from the high pressure region A side (the outer diameter side in this example) to the low pressure region B side (the inner diameter side in this example), the pressure in the high pressure region A is reduced to the low pressure region. The pressure is reduced to the pressure of B. The stationary ring 2 is provided with a notch for forming the intermediate chamber 2A at a position near the outer periphery of a surface facing the rotating ring 1 in the entire circumferential direction. The same pressure as in the high-pressure area A is led by the communication hole 2 </ b> B communicating with the high-pressure area A.

On the other hand, on the side of the rotating ring 1 facing the stationary ring 2, as shown in FIG. 8, a number of spiral grooves 1B are formed at equal intervals in the circumferential direction. The spiral groove 1B has one end (inner peripheral side) formed at the intermediate chamber 2 so that the gas in the seal gap 150 flows into the seal gap 150 by the rotation of the rotary ring 1.
A, and the other end (outer peripheral side) is configured so that the gas passage area is reduced. Thereby, a dynamic pressure bearing utilizing the dynamic pressure of gas accompanying the rotation of the rotary shaft 103 is configured. The dynamic pressure bearing generates a force in the direction of moving the stationary ring 2 to the right in FIG. 7, that is, a floating force with respect to the rotating ring 1, and when the seal clearance 150 decreases, the floating increases. The force increases, and when the seal clearance 150 increases, the floating force decreases, so that the seal clearance 150 acts to be kept constant. Reference numeral 151 denotes an O-ring for sealing between the rotary shaft 103 and the sleeve 101, and reference numeral 155 denotes an O-ring for sealing between the outer periphery of the casing 4 and the main body 153.
It is a ring.

During operation of the compressor provided with the above-mentioned conventional mechanical seal device, the sleeve 101 and the rotary ring 1 are rotated together with the rotary shaft 103 together. At this time, the seal clearance 150 between the rotating rotating ring 1 and the stationary ring 2 at rest is a floating force generated by the dynamic pressure bearing due to the action of the groove 1B.
The mounting position of the secondary seal 4A in the radial direction, the pressure difference between the high-pressure area A and the low-pressure area B, that is, the seal differential pressure,
The spring force received from the compression spring 4C and the retainer 3
It is determined by the balance of the frictional force with the secondary seal 4A.

[0009]

SUMMARY OF THE INVENTION However, FIGS.
The conventional mechanical seal device shown in FIG. 9 has the following problems.

(1) When the inner peripheral side of the stationary ring 2 is deformed by thermal deformation generated by heat generated during operation of the rotating machine or elastic deformation generated by a seal differential pressure, in the conventional case, the inner peripheral side is Unlike the stationary ring outer peripheral side having the dynamic pressure bearing function, since there is no bearing function, there is no means for preventing contact between the rotating ring 1 and the stationary ring 2 when it is attempted.

(2) When the pressure ratio between the high-pressure region A and the low-pressure region B increases, the seal clearance 150
In the vicinity of the outlet, the gas pressure does not drop sufficiently.
In such a state, when the seal clearance 150 increases, the flow rate of the seal clearance 150 increases. For this reason, the outlet pressure of the seal clearance 150 is hardly reduced, and the seal floating force obtained by integrating the pressure distribution in the seal clearance 150 increases. That is, the seal clearance 150
Decreases, the seal floating force also decreases. However,
Desirable characteristics of the mechanical seal are such that when the seal clearance 150 decreases, the seal levitation force increases. Therefore, the above characteristics may cause contact of the seal, that is, contact between the rotating ring 1 and the stationary ring 2. Also in this case, in the above-mentioned conventional one, the stationary ring 1 having the bearing function as in the preceding paragraph.
Unlike the outer peripheral side, since the inner peripheral side has no bearing function, it is difficult to prevent the contact between the rotating ring 1 and the stationary ring 2. For this reason, in order to avoid such contact, it is necessary to more accurately predict the elastic deformation and the thermal deformation of the stationary ring 2 and the pressure distribution in the seal gap than in the past, but such highly accurate prediction is difficult. Therefore, it is difficult to maintain the seal clearance 150 stably.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a non-contact type mechanical seal device, in which a seal clearance provided between a rotating ring and a stationary ring is securely held from the inner periphery to the outer periphery. And to improve the durability of the mechanical seal device.

[0013]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems. The first aspect of the present invention is to provide a rotating ring which is inserted into a rotating shaft and rotates together with the rotating shaft. Can be moved in the axial direction of the rotating shaft by contacting the stationary ring provided non-rotatably and the other side of the stationary ring so as to face the side surface of the rotating ring with a small seal gap. And a casing fixed to a stationary member, and the retainer is inserted into the inner periphery of the casing so as to be movable in the axial direction, and is installed between the casing and the retainer. A preload mechanism for pressing a stationary ring toward the rotating ring; and a sealing means provided at a sliding portion between the retainer and the casing to seal fluid leakage from the sliding portion. And high by sealing means A mechanical seal device for sealing a fluid between a high-pressure region in which a fluid is stored and a low-pressure region such as the atmosphere, wherein a circumferential surface is provided on one side surface of the rotating ring or the stationary ring opposed to the seal clearance. A plurality of grooves are provided along the direction, and a groove for a dynamic pressure bearing in which the fluid in the seal gap is allowed to flow by the rotation of the rotary ring, and the seal gap of one of the rotary ring and the stationary ring. A mechanical seal device comprising: a plurality of first grooves as static pressure bearings provided in the circumferential direction near an outlet on a low-pressure area side; and lands formed between the grooves. .

According to the above-mentioned means, the fluid flowing from the high pressure region into the seal gap formed between the rotating ring and the stationary ring is formed on the side surface of the rotating ring or the stationary ring opposed to the seal gap. Enter the groove. Since the area of the flow passage is reduced at the outlet of the groove, a pressure is generated in this portion, and acts as a dynamic pressure bearing by cooperating with the rotation of the rotating ring. Further, the fluid flows through a large number of grooves provided near the outlet of the rotating ring or the stationary ring on the low pressure region side and lands formed between the grooves, and the grooves and lands have reduced seal clearance. Therefore, the seal clearance is kept constant at all times, and the occurrence of metal contact due to the reduction of the seal clearance is prevented in conjunction with the operation of the dynamic pressure bearing.

The second means is, in addition to the first means, an intermediate chamber in which the stationary ring is formed by cutting a part of a side surface facing the seal clearance along a circumferential direction. And a communication hole for communicating the high-pressure region with the intermediate chamber.

According to this means, the fluid entering the intermediate chamber from the high-pressure region through the communication hole is transferred from the inner peripheral side to the outer peripheral side of the groove provided on the seal clearance side of the rotating ring or the stationary ring together with the centrifugal force of the rotating ring. , The dynamic pressure bearing action due to the pressure increase at the channel area reduced portion at the groove outlet is caused by the first pressure
The effect of maintaining the seal clearance is
More promoted.

Further, in addition to the first means or the second means, the third means includes the first groove portion and the side surface of one of the rotating ring and the stationary ring which faces the seal clearance. A large number of second grooves as stationary bearings are provided along the circumferential direction closer to the high-pressure region than the lands.

According to this means, in addition to the first groove and the land provided on the outlet side of the seal gap to the low-pressure area, the second groove is provided on the inlet side of the seal gap. The function of the hydrostatic bearing is exerted on the inlet side in addition to the outlet side of the seal clearance. As a result, the required seal clearance is more reliably maintained than the first and second means.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to FIGS. 1 to 3 show a mechanical seal device for a compressor according to a first embodiment of the present invention. FIG. 1 is a longitudinal sectional view along a rotation axis, and FIG. 2 is a view from a seal clearance side of a rotary ring. FIG. 3 is a front view of the stationary ring as viewed from the seal clearance side.

In FIGS. 1 to 3, reference numeral 153 denotes a main body of the compressor, 154 denotes an internal housing, and 103 denotes a rotating shaft driven by a driving source (not shown) such as an electric motor. Reference numeral 101 denotes a sleeve fixedly inserted on the outer periphery of the rotating shaft 103, and rotates integrally with the rotating shaft 103. Reference numeral 1 denotes a rotary ring fixedly inserted around the outer periphery of the cylindrical portion of the sleeve 101, and rotates integrally with the sleeve 101 and the rotary shaft 103.
Reference numeral 4 denotes a casing fixed to the inner periphery of the main body 153,
It is fixed to the inner housing 154 by bolts.

Reference numeral 3 denotes a retainer provided inside the casing 4. Reference numeral 2 denotes a stationary ring, and the rotating shaft 103
In the axial direction, the retainer 3 and the rotary ring 1 are provided so as not to rotate between the retainer 3 and the rotary ring 1, and are finely movable in the axial direction together with the retainer 3 by a compression spring 4C described later. The retainer 3 is fitted to the inner periphery of the casing 4 with an appropriate fit to the inner periphery of the casing 4 so that the retainer 3 can be finely moved in the axial direction with respect to the casing 4. A plurality of compression springs 4C are arranged in the inner circumferential direction between the side surface of the retainer 3 on the casing 4 side and the side surface of the casing 4 opposed thereto, and the retainer 3 and the stationary ring 2 are connected to the rotating ring. Pressing to one side.

A is a high-pressure area that communicates with the high-pressure gas passage, B is a low-pressure area that communicates with the atmosphere, and the seal between the high-pressure area A and the low-pressure area B is as follows. The shaft is sealed. That is, 3A is a back O-ring provided at a contact portion between the stationary ring 2 and the retainer 3;
Reference numeral denotes a secondary seal provided in a groove 4B of the casing at a sliding portion between the retainer 3 and the casing 4, and reference numeral 102 denotes an O-ring provided at a contact portion of the sleeve 101 with the rotating ring 1. This compressor prevents gas from leaking from the high-pressure area A to the low-pressure area B by means of the three sealing portions and a shaft sealing means in a seal clearance 150 between the rotating ring 1 and the stationary ring 2 which will be described later. ing.

A small amount of clearance, that is, a seal clearance 150 is formed between the side surface of the rotating ring 1 and the side surface of the stationary ring 2 opposed thereto, and the seal clearance 150 is formed between the high pressure region A and the low pressure region B. Between the pressure boundary.
Then, while the gas passes through the seal clearance 150 from the high pressure region A side (the outer diameter side in this example) to the low pressure region B side (the inner diameter side in this example), the pressure in the high pressure region A is reduced to the low pressure region. The pressure is reduced to the pressure of B. 151
Is an O-ring for sealing between the rotary shaft 103 and the sleeve 101; 155 is an outer periphery of the casing 4 and the main body 1;
An O-ring for sealing between the O-ring and the O-ring 53.

The above configuration is the same as the conventional one shown in FIGS. 1B is a spiral groove formed in the side face of the rotary ring 1 facing the seal clearance 150 at equal intervals in the circumferential direction. This spiral groove 1B
Is rotated by the rotation of the rotary ring 1 so that the seal clearance 150
One side (outer peripheral side) is opened to a portion near the high-pressure area in order to allow the gas inside to flow into the inside thereof,
The other end (inner peripheral side) is configured so that the flow area of the gas is reduced. This constitutes a dynamic pressure bearing utilizing the dynamic pressure of gas accompanying the rotation of the rotary shaft 103.

On the side surface of the stationary ring 2 facing the seal clearance 150, inner grooves 2C are formed at regular intervals in the circumferential direction. This inner groove 2C is provided with the seal clearance 1 described above.
50 is formed in a substantially T-shape at a portion near the outlet toward the low-pressure region B (that is, a portion near the inner periphery), and the groove 2C and the land 2D formed between the grooves 2C are statically formed. It constitutes a pressure bearing.

During operation of the compressor having the mechanical seal device configured as described above, the sleeve 101 and the rotary ring 1 are rotated together with the rotary shaft 103. In the figure, a compressed gas in the compressor is sealed in a high-pressure area A in the compressor, and a low-pressure area B in the compressor.
Is open to the atmosphere. The high-pressure area A and the low-pressure area B are connected to a back O-ring 3A provided at a contact portion between the stationary ring 2 and the retainer 3, and a secondary seal O provided at a sliding portion between the retainer 3 and the casing 4. Ring 4
A, an O-ring 201 on the outer periphery of the casing 4 and an O-ring 102 provided on the inner periphery of the sleeve 101 are sealed so that gas in the high-pressure area A does not leak to the low-pressure area B.

The seal gap 150 formed by the rotating ring 1 and the stationary ring 2 forms a pressure boundary. The gas in the high pressure area A passes through the seal gap 150 toward the low pressure area B. The pressure drops to the pressure in the low pressure area B during the operation. On the other hand, on the surface of the rotating ring 1,
One end is opened to a portion near the high-pressure area A so that the gas in the seal clearance 150 flows into the inside as shown by an arrow in FIG. 1B with a reduced flow passage area
Is provided, and a pressure is generated in a portion where the flow path area is reduced, so that the portion functions as a dynamic pressure bearing. The dynamic pressure bearing generates a force in the direction of moving the stationary ring 2 rightward in FIG. 1 with respect to the rotating ring 1, that is, a floating force. When the seal clearance 150 decreases, the floating increases. The force increases, and when the seal clearance 150 increases, the floating force decreases, so that the seal clearance 15 increases.
0 acts to be kept constant.

The retainer 3 is pressed against the stationary ring 2 by the spring force of the compression spring 4C, and the stationary ring 2 is pressed toward the seal clearance 150,
This pressing force acts as a preload on the dynamic pressure bearing and a static pressure bearing described later.

The pressure in the high pressure area A and the pressure in the low pressure area B
Under the condition where the pressure ratio is high, that is, the pressure ratio is high, the gas flowing from the high pressure region A through the seal clearance 150 does not sufficiently decrease in pressure until just before the inner groove 2C. However, in this embodiment, the seal clearance 15 of the stationary ring 2 is
Since the inner groove and land 2D are provided in the vicinity of the outlet 0, the pressure of the gas flowing through the inner groove 2C in the portion without the notch, that is, the land 2D, reaches the low-pressure area B before reaching the low-pressure area B. Gradually decreases to the pressure in the low-pressure region B, so that the inner groove portion 2C and the land portion 2D
Acts as a hydrostatic bearing in which the seal reaction force increases as the seal clearance 150 decreases.

Therefore, the seal clearance 150 formed by the side surface of the rotating ring 1 and the side surface of the stationary ring 2 is capable of increasing the floating force due to the action of the dynamic pressure bearing and the O-ring 4 for the secondary seal.
A, the pressure difference between the high pressure area A and the low pressure area B, that is, the seal differential pressure, the spring force received from the compression spring 4C, and the frictional force between the retainer 3 and the O-ring 4A for the secondary seal. , And the floating force of the hydrostatic bearing formed by the inner groove 2C and the land 2D.

The dynamic and static pressure bearings are
When the seal clearance 150 decreases, the levitation force increases, and when the seal clearance 150 increases, the levitation force decreases. Here, under the condition that the operation is performed with the seal differential pressure and the rotation speed kept constant, the force other than the floating force of the bearing may be regarded as constant, so that the seal clearance 150 is always kept constant.

FIG. 4 shows a second embodiment of the present invention. In this embodiment, the stationary ring 2 is provided with an intermediate chamber 2A and a communication hole 2B similar to the conventional one shown in FIGS. That is, the stationary ring 2 is provided with a notch for forming the intermediate chamber 2A at a position near the outer periphery of the surface facing the rotating ring 1 over the entire circumferential direction.
The same pressure as in the high pressure area A is guided by the communication holes 2B communicating with the high pressure area A. Other configurations are shown in FIG.
3 is the same as that of the first embodiment shown in FIG. 3, and the same members are denoted by the same reference numerals.

In this embodiment, the gas in the high-pressure area A enters the intermediate chamber 2A through the communication hole 2B. The intermediate chamber 2A has a spiral groove 1B provided in the rotary ring 1.
(See FIG. 2), so that the intermediate chamber 2
The gas in A flows into the spiral groove 1B as shown by the arrow in FIG. 2, and a pressure is generated because the flow path area is reduced at the portion exiting the groove 1B, and the pressure is generated as in the first embodiment. Acts as a hydrodynamic bearing.

In this embodiment, by forming the communication hole 2B and the intermediate chamber 2A, the gas in the high-pressure area A can be separated from the spiral groove 1B formed in the rotary ring 1 together with the centrifugal force generated by the rotation of the rotary ring 1. Since it is pushed in from the circumferential side to the outer circumferential side, the dynamic pressure bearing action due to the pressure increase at the flow path area reduced portion at the outlet of the groove 1B becomes larger than in the first embodiment, and the action of maintaining the seal clearance is more reliably performed. .

FIGS. 5 and 6 show a mechanical seal device according to a third embodiment of the present invention. In this embodiment, in addition to the gas outlet side of the stationary ring 2 to the low-pressure area B, a groove 2E serving as a hydrostatic bearing is provided on the gas inlet side. That is, in FIG. 6, the stationary ring 2 has an inner peripheral side in the first and second embodiments (an outlet side to the low pressure region B).
In addition, a large number of outer groove portions 2E are provided at equal intervals along the inner circumferential direction in the outer circumferential side, that is, in a portion near the high-pressure area A. Other configurations are the same as those of the first embodiment, and the same members are denoted by the same reference numerals.

In this embodiment, the gas that has flowed into the seal clearance 150 from the high-pressure area A is provided with the outer groove 2E on the outer peripheral side (a part near the high-pressure area A).
At this portion, the flow path area is reduced, and pressure is generated. Thereby, in addition to the outlet side to the low-pressure area B where the inner groove 2C is provided, the function of the hydrostatic bearing is performed not only on the inlet side near the high-pressure area A, but also the formation of the seal clearance 150 is more reliably performed. Done.

In each of the above embodiments, the groove 1B is provided in the rotary ring 1 instead of the seal clearance 1 of the stationary ring 2.
A groove similar to the above-described groove 1B may be provided on a side surface facing 50. In the first, second and third embodiments, the inner groove 2C and the land 2D provided on the stationary ring 2 may be provided on the rotary ring 1 side, and the outer groove 2E in the third embodiment is also provided on the rotary ring side. May be provided.

[0038]

The present invention is configured as described above.
According to the first aspect of the present invention, the action of the dynamic pressure bearing in cooperation with the rotation of the rotating ring of the groove provided on the side surface of the rotating ring or the stationary ring facing the seal clearance, and the low pressure of the rotating ring or the stationary ring. The seal clearance is always maintained at a required value by the hydrostatic bearing action of the groove and the land provided near the region-side outlet, so that the metal contact of the seal can be prevented.

According to the second aspect of the present invention, in addition to the above, the fluid which has entered the intermediate chamber from the high-pressure region through the communication hole is provided on the seal clearance side of the rotating ring or the stationary ring together with the centrifugal force of the rotating ring. Since the groove portion is pushed from the inner peripheral side to the outer peripheral side, the dynamic pressure bearing action by the pressure increase at the flow path area reduction portion at the groove outlet becomes larger than that of the first means, and the action of maintaining the seal clearance is more improved. The effect of being promoted is obtained.

According to the third aspect of the present invention, in addition to the above, in addition to the first groove and the land provided on the outlet side of the seal gap to the low pressure region, the second groove is also provided on the inlet side of the seal gap. Are provided, the effect of the hydrostatic bearing is exerted not only on the outlet side of the seal clearance but also on the inlet side. As a result, the required seal clearance is more reliably maintained than the first and second means.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a mechanical seal device for a gas compressor according to a first embodiment of the present invention.

FIG. 2 is a front view of the rotating ring in the first embodiment.

FIG. 3 is a front view of a stationary ring according to the first embodiment.

FIG. 4 is an equivalent view of FIG. 1 showing a second embodiment of the present invention.

FIG. 5 is an equivalent view of FIG. 1 showing a third embodiment of the present invention.

FIG. 6 is a front view of a stationary ring according to the third embodiment.

FIG. 7 is a longitudinal sectional view showing a conventional mechanical seal device.

FIG. 8 is a front view of a rotating ring in the conventional example.

FIG. 9 is an enlarged view of a portion Z in FIG. 7;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Rotating ring 1B Groove part 2 Stationary ring 2A Intermediate chamber 2B Communication hole 2C Inner groove part 2D Land part 2E Outer groove part 3 Retainer 3A Back O-ring 4 Casing 4A Secondary seal 4B O-ring 4C Compression spring 101 Sleeve 102 O-ring 103 Rotating shaft 150 Seal Clearance 153 Body A High pressure area B Low pressure area

Claims (3)

[Claims] 1. A rotating ring which is inserted into a rotating shaft and rotates together with the rotating shaft, and is provided non-rotatably such that one side faces the side surface of the rotating ring with a small seal clearance. A stationary ring, a retainer provided in contact with the other side surface of the stationary ring so as to be movable in the axial direction of the rotary shaft, and a retainer fixed to the stationary member and capable of axially moving the retainer on the inner periphery. A casing inserted between the casing and the retainer, a preload mechanism that presses the stationary ring toward the rotating ring via the retainer, and a sliding portion between the retainer and the casing. Provided,
A seal means for sealing fluid leakage from the sliding portion, wherein the seal clearance and the seal means seal the fluid between a high-pressure area in which high-pressure fluid is stored and a low-pressure area such as the atmosphere. A device, a number of which are provided along the circumferential direction on either side surface of the rotating ring or the stationary ring opposed to the seal clearance,
A groove portion for a dynamic pressure bearing in which the fluid in the seal gap is allowed to flow by the rotation of the rotary ring, and a circumference near the low pressure region side outlet of the seal gap of either the rotary ring or the stationary ring. A mechanical seal device comprising: a plurality of first grooves as static pressure bearings provided along a direction; and lands formed between the grooves. 2. The communication hole that communicates between the intermediate chamber formed by cutting a part of a side surface facing the seal clearance along a circumferential direction and the high-pressure region with the intermediate chamber. The mechanical seal device according to claim 1, comprising: 3. A second groove as a hydrostatic bearing on a side surface of one of the rotating ring and the stationary ring opposed to the seal clearance, closer to the high pressure region than the first groove and the land. 3. The mechanical seal device according to claim 1, wherein a large number of the seals are provided along the circumferential direction.