JP3206843U - mechanical seal - Google Patents

Abstract

A mechanical seal that prevents a rotating ring from falling off a sleeve due to its own weight and that allows the rotating ring to be easily assembled and removed from the sleeve. A sleeve 11 fixed to an outer peripheral surface of a rotating shaft of a device to be mounted, and a rotating ring 10 attached with an inner peripheral surface facing the outer peripheral surface of the sleeve and rotating in accordance with the rotation of the rotating shaft. And an O-ring 12 fitted between the inner peripheral surface of the rotating ring and the outer peripheral surface of the sleeve, and a surface perpendicular to the axial direction of the rotating ring and the non-rotating ring 20 facing the surface. A mechanical seal that seals the contents of the device to be mounted by sliding with each other, and an O-ring is provided on each of the inner peripheral surface of the rotating ring and the outer peripheral surface of the sleeve that the O-ring contacts. Concave grooves P1 and P2 to be pressed are provided. [Selection] Figure 3

Description

  The present invention relates to a mechanical seal, and more particularly, to a mechanical seal using an O-ring between a rotating ring and a sleeve.

  The mechanical seal forms a seal surface by slidingly contacting the end face of the rotating ring mounted on the rotating shaft and the end face of the non-rotating ring mounted on the casing (equipment) side, and the axial direction of the rotating shaft (the pressing direction) It is widely used in various fields as a sealing device that seals between a rotating shaft and a casing (apparatus) by being pressed in the axial direction by a spring that is hung on the shaft.

  The rotating ring is mounted on the rotating shaft of the motor and rotates together with the rotating shaft, and the non-rotating ring is mounted on a stationary member such as a casing (device) and does not rotate. This non-rotating ring is in sliding contact with the rotating ring and receives rotational force due to frictional resistance.

  In addition, since the seal surface wears as the mechanical seal is used, it is necessary to compensate for this, and in order to follow vibration and shaft runout, either a rotating ring or a non-rotating ring can be moved in the axial direction. It is common to configure as In other words, in order to cope with wear and vibration of the seal surface and to maintain the contact pressure of the seal surface, either the rotating ring or the non-rotating ring can be driven in the axial direction, and the spring is pressed in the sealing surface direction. It is necessary to keep.

  As described above, the non-rotating ring is mounted on the casing (equipment) side. The non-rotating ring is sealed with an O-ring between the casing (equipment) and the like and can be driven by sliding with the O-ring. It is common to configure. As is well known, an O-ring is one that exerts a sealing function by closely contacting an object by applying a predetermined pressure. In the case of a mechanical seal, the O-ring is usually a casing (equipment) or a rotating shaft. A configuration is adopted in which the groove is formed in a groove formed in the mounting body, the depth of the groove is made smaller than the cross-sectional diameter of the O-ring, and the O-ring is tightened by the groove to be in close contact with the mounting body.

Japanese Patent Publication No. 08-014322

  Conventionally, the rotary ring has a structure in which the rotating ring does not easily come out regardless of the direction in which the mechanical seal is placed due to the frictional resistance of the O-ring and the pressing force due to the spring load. Under such circumstances, silicon carbide, cemented carbide or the like is selected as the material of the rotating ring according to the corrosion resistance against the fluid inside the machine, the sliding characteristics, the cost, and the like.

  However, since the rotating ring made of cemented carbide is heavy, it may not be supported only by the frictional resistance and spring load of the conventional O-ring, and the rotating ring is held so as not to fall off. That was a problem.

  In particular, when the mechanical seal is packed and transported to the site where the rotating shaft of the target device is placed, the mechanical seal is placed with the spring down and the rotating ring up (hereinafter referred to as “downward It is sometimes referred to as “the state of”). At this time, there has been a problem that the rotating ring falls off the sleeve due to external factors such as impact during transportation.

  In order to solve this problem, if the load of the spring is increased, the pressing force of the seal surface is increased and the product performance is affected. Therefore, there is a certain limit to increasing the load. Further, when the frictional resistance of the O-ring is increased, the frictional resistance when the rotating ring is fitted into the sleeve increases, and it becomes difficult to incorporate the O-ring. Therefore, it has been difficult to prevent the rotating ring from falling off by adjusting the spring load and the frictional resistance of the O-ring.

  It is also conceivable to prevent the rotating ring from falling off by using a holding plate such as a snap ring or to prevent the rotating ring from falling off by fastening the rotating ring and the sleeve with a bolt or the like. Since the space area where the mechanical seal is attached to the rotation shaft is very narrow, it is difficult to adopt these structures.

  Therefore, the present invention has been made in view of the circumstances described above, and its purpose is to provide a rotating ring even when the mechanical seal is mounted in a downward state under a condition where the mounting space area is very narrow. It is intended to provide a mechanical seal that prevents the rotating ring from falling off the sleeve due to its own weight, can be easily assembled to the sleeve, and can be easily removed from the sleeve. .

  In order to solve the above-described problems, the present invention provides a sleeve fixed to the outer peripheral surface of the rotating shaft of the device to be mounted, and an inner peripheral surface attached to the outer peripheral surface of the sleeve so as to face the outer peripheral surface of the sleeve. A rotating ring that rotates according to rotation; and an O-ring that is fitted between an inner peripheral surface of the rotating ring and an outer peripheral surface of the sleeve, and rotates according to the rotation of the rotating shaft. A mechanical seal that seals the contents of the mounting target device by sliding a surface perpendicular to the axial direction of the rotating ring and a surface of the non-rotating ring facing the surface perpendicular to the axial direction of the rotating ring. In the mechanical seal, a concave groove for pressing the O-ring is provided in each of the inner peripheral surface of the rotating ring and the outer peripheral surface of the sleeve, which are in contact with the O-ring. .

  Further, the present invention provides the mechanical seal according to claim 1, wherein when the rotary ring is attached to the sleeve, the inner peripheral surface of the rotary ring that faces the outer peripheral surface of the sleeve first is chamfered. The mechanical seal is characterized in that the angle is gentle compared to the chamfering angle of the concave groove provided on the inner peripheral surface of the rotating ring.

  Furthermore, in order to solve the above-described problems, the present invention provides a sleeve fixed to the outer peripheral surface of the rotating shaft of the device to be mounted, and a rotating ring back metal fitted to the sleeve via an O-ring. A rotating ring that is fitted to the rotating ring back metal via an O-ring and rotates according to the rotation of the rotating shaft, and is perpendicular to the axial direction of the rotating ring that rotates according to the rotation of the rotating ring. A non-rotating ring is a mechanical seal that seals the contents of the device to be mounted by sliding a surface and a surface of the non-rotating ring facing the surface perpendicular to the axial direction of the rotating ring. Non-rotating ring back metal fitted to the non-rotating ring back metal with respect to the non-rotating ring back metal, and an annular retainer fitted to the non-rotating ring back metal with respect to the outer peripheral surface of the retainer Inner surface is through O-ring And a ground cover to be fitted, and each of the inner peripheral surface of the ground cover and the outer peripheral surface of the retainer is provided with a groove for pressing the O-ring. It is a seal.

  According to the present invention, the rotating ring is prevented from falling off the sleeve due to its own weight, the rotating ring can be easily assembled to the sleeve, and the rotating ring can be easily detached from the sleeve. A mechanical seal can be obtained.

It is sectional drawing which shows the state with which the mechanical seal in embodiment of this invention was mounted | worn with the rotating shaft. It is a principal part enlarged view of the cross section which shows the state with which the conventional mechanical seal was mounted | worn with the rotating shaft. It is a principal part enlarged view of the A section of FIG. 1 which is sectional drawing which shows the state with which the mechanical seal in embodiment of this invention was mounted | worn with the rotating shaft. It is a figure explaining the detail of the ditch | groove in which the O-ring which seals between the sleeve and rotary ring of a mechanical seal in embodiment of this invention is inserted. It is a principal part enlarged view of the cross section which shows the state with which the mechanical seal in other embodiment of this invention was mounted | worn with the rotating shaft.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In addition, the same code | symbol is attached | subjected to the common part in each figure. FIG. 1 is a cross-sectional view showing a state where a mechanical seal according to an embodiment of the present invention is attached to a rotating shaft.

  In FIG. 1, a mechanical seal 100 is mounted on a rotating shaft J of a casing (device) C of a rotating machine that is a device to be mounted, and seals between the rotating shaft J and the casing (device) C, so that the in-machine Y It is the structure which seals the leak to the atmosphere X side from the side. In this case (in the case of FIG. 1), the in-machine Y side is at a high pressure, and the atmosphere X side is at a low pressure.

  The mechanical seal 100 has a sleeve 11 attached to the outer peripheral surface of the rotating shaft J via an O-ring 13 and an inner peripheral surface fitted to the outer peripheral surface of the sleeve 11 via an O-ring 12 and a pin 14. The rotary ring 10 rotates integrally with the rotary shaft J. The rotating ring 10 is rotatably mounted on the rotating shaft J and is a non-driven rotating ring.

  Furthermore, the mechanical seal 100 includes a non-rotating ring 20 having an end surface that forms a sealing surface S by sliding contact with an end surface of the rotating ring 10, that is, a surface perpendicular to the axial direction of the rotating shaft J, and the non-rotating ring 20. And a back metal 24 fitted through an O-ring 28 and a pin 23. The non-rotating ring 20 is movable in the axial direction of the rotating shaft J with respect to the casing C via the back metal 24, and is driven according to the movement of the rotating shaft J in the axial direction and the wear of the seal surface S. It is configured to be able to. The non-rotating ring 20 is pressed in the direction of the seal surface S by a spring 26.

  Next, a main part of a cross section showing a state in which a conventional mechanical seal is mounted on a rotating shaft will be described. FIG. 2 is an enlarged view of an essential part of a cross section showing a state in which a conventional mechanical seal is mounted on a rotating shaft.

  In FIG. 2, parts that are the same as those in FIG. 1 are given the same reference numerals. FIG. 2 is an enlarged view of a portion surrounded by a dotted line A in FIG. 1 when a conventional mechanical seal is mounted on a rotating shaft.

  In the conventional mechanical seal 100 ′ shown in FIG. 2, when the mechanical seal 100 ′ is packed and transported toward the site where the rotating shaft J of the device to be mounted is placed, the mechanical seal 100 ′ has the spring 26. There is a case where the rotary ring 10 is placed on the lower side (a state in which the rotary ring 10 is vertically placed with the arrow Z direction in FIG. 2 down, hereinafter referred to as a “downward state”).

  At this time, there was a problem that the rotating ring 10 would fall out of the sleeve 11 due to external factors such as impact during transportation. The present invention solves this problem without changing the load of the spring 26 and the frictional resistance of the O-ring 12 and without using any other member. Hereinafter, embodiments of the present invention will be specifically described.

  FIG. 3 is an enlarged view of a main part of the portion A in FIG. 1, which is a cross-sectional view showing a state in which the mechanical seal in the embodiment of the present invention is attached to the rotating shaft.

  In FIG. 3, the contact surface of the O-ring 12 fitted between the outer peripheral surface of the sleeve 11 and the inner peripheral surface of the rotary ring 10 is a concave groove P1 provided on the outer peripheral surface side of the sleeve 11 and the rotary ring 10. It is supposed that it is made to contact between the ditch | groove P2 provided in the inner peripheral surface side. That is, conventionally, the contact surface of the O-ring 12 fitted between the outer peripheral surface of the sleeve 11 and the inner peripheral surface of the rotary ring 10 is the outer peripheral surface of the sleeve 11 or the rotary ring 10 as shown in FIG. A concave groove P (in the case of FIG. 2, a concave groove P is provided on the outer peripheral surface side of the sleeve 11) and an inner peripheral surface of the rotary ring 10 or the sleeve 11 are provided on either one of the inner peripheral surfaces. In the embodiment of the present invention, the groove P1 provided on the outer peripheral surface of the sleeve 11 and the concave provided on the inner peripheral surface of the rotary ring 10 are in contact with one of the outer peripheral surfaces. The rotating ring 10 is held by the frictional resistance of the O-ring 12 that contacts both the recessed groove P1 of the sleeve 11 and the recessed groove P2 of the rotating ring 10 by making contact with the groove P2.

  In other words, by providing the concave groove P2 on the inner peripheral surface of the rotary ring 10, a mechanical resistance 100 is formed between the concave groove P2 of the rotary ring 10 and the O-ring 12, thereby newly forming the mechanical seal 100 as a spring. Even when the rotary ring 10 is placed in a state where the rotary ring 10 is directed downward (a state in which the rotary ring 10 is vertically placed with the arrow Z direction in FIG. 3 downward), the rotary ring 10 is removed from the sleeve 11 by its own weight. It is intended to prevent falling out.

  2 and 3, the height dimension H of the O-ring 12, that is, the collapse amount of the O-ring 12 itself is not changed. That is, the depth dimension H of the concave groove P provided on the outer peripheral surface of the sleeve 11 in FIG. 2, the depth dimension of the concave groove P1 provided on the outer peripheral surface of the sleeve 11 in FIG. The sum H ′ with the depth dimension of the concave groove P2 provided on the surface is the same. By providing the concave groove P1 on the outer peripheral surface of the sleeve 11 and the concave groove P2 on the inner peripheral surface of the rotary ring 10, the tightening margin for the O-ring 12 by the sleeve 11 and the rotary ring 10 is changed as compared with the conventional structure. Without stopping, the catching resistance (friction resistance) to the O-ring 12 is increased.

  Next, details of the concave groove into which the O-ring for sealing between the sleeve of the mechanical seal and the rotating ring in the embodiment of the present invention is inserted will be described. FIG. 4 is a view for explaining the details of the concave groove into which the O-ring for sealing between the sleeve of the mechanical seal and the rotary ring in the embodiment of the present invention is inserted.

  According to the experiment by the applicant, when the load of the rotating ring 10 was measured using the O-ring 12 made of fluororubber having a predetermined wire diameter and the rotating ring 10 made of cemented carbide having a predetermined weight, An optimum depth dimension D of the concave groove P2 of the rotating ring 10 for obtaining a load that is ten times or more the own weight of the ring 10 could be obtained. As shown in FIG. 4, when the O-ring is fitted / removed between the rotary ring 10 and the sleeve 11, the O-ring 12 is rotated so that the O-ring 12 can be easily fitted / removed without damaging the O-ring 12. When the ring 10 is attached to the sleeve 11, a chamfer C ′ is provided on the inner peripheral surface of the rotating ring 10 that faces the outer peripheral surface of the sleeve 11 first, and a chamfer C is provided in the concave groove P 2 of the rotating ring 10. It is preferable to make the angle of the chamfer C ′ gentle compared to the angle of the chamfer C.

  Next, an essential part of a cross section showing a state in which a mechanical seal according to another embodiment of the present invention is mounted on a rotating shaft will be described. FIG. 5 is an enlarged view of an essential part of a cross section showing a state in which a mechanical seal according to another embodiment of the present invention is attached to a rotating shaft.

  In FIG. 5, the rotating ring 10 is fitted to the rotating ring back metal 15 via an O-ring 16. Further, the non-rotating ring 20 is fitted to the non-rotating ring back metal 21 through the O-ring 17. A non-rotating ring back metal 21 is connected to a compling 22, and is biased in the direction of the rotating ring 10 by a spring 26 via the compiling 22.

  The ground cover 30 covers the outer side of the rotating ring 10 in a sealed state, and is attached to the casing (device) C via the O-ring 18. The annular retainer 27 is used to fit the non-rotating ring back metal 21 through the O-ring 19. The casing (equipment) C side has an opening (not shown) having a diameter larger than the outer diameter of the compression ring 22. Is formed, and the retainer 27 is attached thereto. When the mechanical seal 100 is assembled, the spring 26 and the comping ring 22 are attached from this opening, and then the retainer 27 is attached.

  Then, the mechanical seal 100 is incorporated in the rotation shaft J of the mounting target device in a state where the rotary ring 10 is directed downward and the retainer 27 is directed upward (a state in which the mechanical seal 100 is vertically placed with the arrow W direction in FIG. Even if it is a case, the retainer 27 is prevented from falling off the ground cover 30 due to its own weight.

  Specifically, the O-ring 25 fitted between the retainer 27 and the ground cover 30 is conventionally attached to either the retainer 27 or the ground cover 30 as described in the above embodiment. Whereas the recessed groove provided is in contact with either the ground cover 30 or the flat surface of the retainer 27, in another embodiment of the present invention, as shown in FIG. The retainer 27 is brought into contact with both the recessed groove of the retainer 27 and the recessed groove of the ground cover 30 by contacting the provided recessed groove and the recessed groove provided on the inner peripheral surface of the ground cover 30. It is supposed to be held by the frictional resistance of the ring 25.

  As described above, the present invention provides a sleeve that is fixed to the outer peripheral surface of the rotating shaft of the device to be mounted, and a rotation that is attached with the inner peripheral surface facing the outer peripheral surface of the sleeve and rotates according to the rotation of the rotating shaft. A ring, and an O-ring fitted between the inner peripheral surface of the rotary ring and the outer peripheral surface of the sleeve, and rotating with a plane perpendicular to the axial direction of the rotary ring rotating according to the rotation of the rotary shaft In the mechanical seal that seals the contents of the device to be mounted by sliding the surface perpendicular to the axial direction of the ring and the surface of the non-rotating ring facing each other, the inner peripheral surface of the rotating ring that contacts the O-ring And a groove for pressing the O-ring is provided in each of the outer peripheral surface of the sleeve. This prevents the rotating ring from falling off the sleeve due to its own weight, and allows the rotating ring to be easily assembled to the sleeve and allows the rotating ring to be easily detached from the sleeve. Can be obtained.

  As mentioned above, although embodiment of this invention was described so far, embodiment of this invention is not limited to embodiment mentioned above. That is, other embodiments, additions, changes, deletions, and the like can be changed within a range that can be conceived by those skilled in the art, and within the scope of the present invention as long as the effects of the present invention are exhibited in any aspect. It is included.

DESCRIPTION OF SYMBOLS 10 Rotating ring 11 Sleeve 12, 13, 16, 17, 18, 19, 25, 28 O-ring 14, 23 Pin 15 Rotating ring back metal 20 Non-rotating ring 21 Non-rotating ring back metal 22 Compling 24 Back metal 26 Spring 27 Retainer 30 Ground cover 100, 100 'Mechanical seal

Claims (3)

A sleeve fixed to the outer peripheral surface of the rotating shaft of the target device;
A rotating ring that is attached with an inner peripheral surface facing the outer peripheral surface of the sleeve and rotates according to the rotation of the rotating shaft;
An O-ring fitted between the inner peripheral surface of the rotating ring and the outer peripheral surface of the sleeve;
Including at least
The surface perpendicular to the axial direction of the rotating ring rotating in accordance with the rotation of the rotating shaft and the surface of the non-rotating ring facing the surface perpendicular to the axial direction of the rotating ring slide with each other, thereby A mechanical seal that seals the contents of the device to be installed,
A mechanical seal, wherein a concave groove for pressing the O-ring is provided on each of an inner peripheral surface of the rotating ring and an outer peripheral surface of the sleeve, which are in contact with the O-ring.   When the rotating ring is attached to the sleeve, the chamfering angle of the inner peripheral surface of the rotating ring that faces the outer peripheral surface of the sleeve first is a concave groove provided on the inner peripheral surface of the rotating ring. The mechanical seal according to claim 1, wherein the mechanical seal is gentler than a chamfer angle. A sleeve fixed to the outer peripheral surface of the rotating shaft of the target device;
A rotating ring back metal fitted to the sleeve via an O-ring;
A rotating ring that is fitted to the rotating ring back metal via an O-ring and rotates according to the rotation of the rotating shaft;
The surface perpendicular to the axial direction of the rotating ring that rotates in accordance with the rotation of the rotating ring and the surface of the non-rotating ring that faces the surface perpendicular to the axial direction of the rotating ring slide with each other, thereby A mechanical seal that seals the contents of the device to be installed,
A non-rotating ring back metal fitted via an O-ring to the non-rotating ring;
An annular retainer fitted via an O-ring to the non-rotating ring back metal;
A ground cover whose inner peripheral surface is fitted via an O-ring with respect to the outer peripheral surface of the retainer;
Further including
A mechanical seal, wherein a concave groove for pressing the O-ring is provided on each of an inner peripheral surface of the ground cover and an outer peripheral surface of the retainer.

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