JPH0771616A - Shaft seal device - Google Patents

Abstract

PURPOSE:To improve the sealability at the sliding surface of the slide ring and suppress the wear of this sliding surface, by reducing the deterioration in the axial operability of a slide-ring-side seal member due to excessive torque and suppressing the occurrence of thermal distortion of the retainer. CONSTITUTION:Circular-arc like segments of retainers 103, 105 are respectively connected by both protrusion pieces 103b thereof, and both protrusion pieces 105b thereof, each protrusion piece being projectively formed at both circumferential ends of each corresponding segment. The protrusion pieces 103b of the stationary side retainer 103 are circumferentially engaged with a notch 118 formed in a housing 1 while the protrusion pieces 105b of the rotary side retainer 105 are circumferentially engaged with a notch 119 formed in a rotary side collar 106.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shaft-sealing device for sealing a shaft by causing sliding rings arranged on a stationary side and a rotating side to be closely slid against each other at their axially opposed end faces. In particular, it relates to a sliding ring having a structure divided in the circumferential direction.

[0002]

2. Description of the Related Art Some of fluid devices such as industrial pumps, turbines, compressors, etc. are extremely difficult to disassemble and assemble when they are large-sized devices. Therefore, the shaft sealing device mounted on such equipment has a structure in which some or all of the parts are circumferentially divided for the purpose of reducing the labor required for disassembling and assembling the equipment during maintenance. It is common to do.

FIG. 3 shows a typical conventional example of this type of shaft seal device. Reference numeral 1 is a housing of the device, and 2 is a rotary shaft. The shaft sealing device 3 has a pair of sliding rings 31 and 32 in which a plurality of arc-shaped pieces are combined in an annular shape. Of these, one stationary side sliding ring 31 is a circumferential groove extending in the circumferential direction of the stationary side retainer 33, which is held by the housing 1 via a packing 34 so as to be axially movable and is prevented from rotating by a pin 35. 33a, and the other rotation side sliding ring 32 is incorporated in a circumferential groove 36a of the rotation side retainer 36 fixed to the collar 37 on the outer circumference of the rotation shaft 2 via a bolt 38 and extending in the circumferential direction. Has been. The stationary side sliding ring 31 is axially pressed by a spring (not shown) via a retainer 33, so that the stationary side sliding ring 31 is in sliding contact with the rotating side sliding ring 32 that rotates together with the rotating shaft 2 in a sealed manner, and rotates with the housing 1. The shaft is sealed with the shaft 2.

The housing 1, the retainers 33 and 36, and the collar 37 are also divided into a plurality of portions in the circumferential direction like the sliding rings 31 and 32, and are annularly connected to each other by bolts. There is. Of these, the retainers 33 and 36 have bolts 33c and 3b formed by projecting pieces 33b and 36b protruding from the outer peripheral portions of both ends of the arc-shaped fragment in the circumferential direction.
It is fixed via 6c and is thereby integrated in a ring shape.

[0005]

The above-mentioned conventional shaft sealing device has the following problems. The protrusion 36b of the rotary retainer 36 rotates integrally with the rotary shaft 2 to generate a pumping force similar to that of an impeller, forcibly rotating the surrounding fluid. Since this fluid collides with the protruding piece 33b of the stationary side retainer 33 and loads the fluid pressure, the pin 35 that prevents the stationary side retainer 33 from rotating.
In addition to the friction torque on the sliding surfaces S of the sliding rings 31 and 32, the torque due to the fluid pressure acts on the.
Therefore, the pin 35 is significantly worn by friction with the inner surface of the engagement hole 1a on the housing 1 side. In order to maintain a proper close contact between the stationary side and the rotating side sliding rings 31 and 32 on the sliding surface S and to obtain excellent sealing performance, the rotary shaft 2
Rotating side sliding ring 32 and retainer 3 due to axial displacement of
It is indispensable that the stationary side sealing member composed of the stationary side retainer 33 and the stationary side sliding ring 31 responds to the axial behavior of the rotating side sealing member composed of 6 and the collar 37 etc. with good responsiveness. However, if the pin 35 is worn and a step is formed on the surface thereof, the follow-up operability of the stationary side sealing member in the axial direction is impaired, so that the sliding surface S
May cause excessive leakage, or may cause abnormal wear or heat generation on the sliding surface S.

Further, the projecting pieces 3 on the outer circumference of the retainers 33 and 36
3b and 36b act as a kind of heat dissipation plate, and radiate the heat from the sliding surface S of the sliding rings 31 and 32 into the fluid. However, since the protrusions 33b and 36b are present at intervals such as the circumferentially divided position, the retainers 33 and 3 are separated.
In No. 6, the temperature becomes non-uniform in the circumferential direction, and the difference in thermal expansion causes distortion. Therefore, the sliding ring 3
An excessive leakage occurs due to a gap due to thermal strain between the sliding surfaces S of the first and the second sliding surfaces S, or the sliding surface S is brought into a local contact state due to the strain, so that the contact pressure increases. May cause abnormal wear.

Therefore, the main object of the present invention is to prevent the axial operability of the sealing member from decreasing due to excessive torque and the occurrence of thermal strain in the retainer, and to prevent the sliding surfaces of the stationary and rotating sliding rings from sliding. It is intended to improve the sealing performance in the above and suppress the abrasion of the sliding surface.

[0008]

The above-mentioned technical problems are as follows.
The present invention can effectively solve the problem. That is, in the shaft sealing device of the present invention, the arcuate pieces of the retainer are joined by the projecting pieces formed on both ends in the circumferential direction of the retainer, and the projecting pieces of the stationary side retainer are formed on the stationary side housing. The notch is circumferentially engaged, and the protrusion of the rotating side retainer is circumferentially engaged with the notch formed in the rotating collar.

[0009]

The projecting pieces at both ends in the circumferential direction of the arc-shaped piece of the retainer are formed by the joining means for joining the pieces into a ring shape and the circumferential direction of the stationary housing or the rotating collar. It also serves as an engaging (rotating) means. This circumferential engagement is performed in a state where the respective projecting pieces are housed in the notches formed in the housing and the collar, so that the forced rotation of the fluid by the projecting pieces of the rotating side retainer is suppressed. At the same time, the increase in torque due to the resistance of the fluid can be suppressed, and the occurrence of temperature unevenness in the circumferential direction of the retainer due to the heat radiation effect of the projecting piece can also be suppressed. Further, since each of the projecting pieces is in flat contact with the inner surface of each of the cutouts, the contact area is increased as compared with the conventional pin engaging structure, so that wear of the contacting part is suppressed.

[0010]

1 and 2 show a preferred embodiment of a shaft sealing device according to the present invention, in which reference numeral 1 is a housing of an apparatus and 2 is a rotary shaft. The housing 1 is divided into two parts in the circumferential direction, and the divided part is connected to the flange 11 through a plurality of bolts 12 and a gasket (not shown).
And a plurality of annular members such as a seal case 13 which is similarly divided into two in the circumferential direction and whose divided portions are connected via a plurality of bolts 14 and gaskets not shown and whose inner diameter is smaller than the inner diameter of the flange 11. It is connected in the axial direction via bolts 15 and 16 and packings 17 and 18.

The shaft sealing device 10 of this embodiment, which seals the space between the housing 1 and the rotary shaft 2, has a stationary side in which two semi-circular sliding ring pieces each made of, for example, SiC are annularly combined and A pair of sliding rings 101, 1 on the rotating side
Have 02. In the seal case 13 of the housing 1,
A metal stationary retainer 103 is axially movably supported via a packing 104 slidingly contacting the inner peripheral surface of the collar 10 fixed to the sleeve 21 of the rotary shaft 2.
6, a rotary side retainer 105 axially opposed to the stationary side retainer 103 is arranged via a packing 107. Circumferential grooves 103a and 105a extending in the circumferential direction are formed on the end surfaces of the retainers 103 and 105 that face each other, and the stationary slide ring 101 rotates in the circumferential groove 103a of the stationary retainer 103 and also rotates. Side sliding ring 102
Are incorporated in the circumferential grooves 105a of the rotary side retainer 105, respectively.

Each of the retainers 103 and 105 is divided into two semicircular arc-shaped retainer pieces at two circumferential positions. Reference numerals 103A and 103B in FIG. 2 indicate retainer pieces that form the retainer 103 on the stationary side. The back surface (circumferential grooves 103a, 1) of both ends of each retainer piece in the circumferential direction.
Plate-like projecting pieces 103b and 105b extending in the radial direction are respectively provided on the surface opposite to the end surface on which 05a is formed), and the projecting pieces 103b and 105b facing each other are provided in a required number. Fastening members 108, 10
By being fastened at 9, annular retainers 103, 1
05 is assembled. Further, the rotating side collar 106 is also divided into two semicircular shapes in the circumferential direction, and has a structure in which the collar 106 is annularly coupled via a coupling means such as a bolt (not shown).

On the outer peripheral surfaces of the sliding rings 101 and 102,
Cushioning rings 110, 11 formed by bonding both ends of an elongated elastomeric member having a circular cross-section into an annular (O-ring) shape
1 is installed. Metal holders 112, 113 are arranged on the outer peripheral sides of the buffer rings 110, 111, and are fastened and fixed to the retainers 103, 105 via bolts 114, 115, respectively. By compressing between the tapered surface formed on the inner diameter of the holders 112 and 113, the outer peripheral surfaces of the sliding rings 101 and 102, and the end surfaces of the retainers 103 and 105, each piece of the sliding rings 101 and 102 is compressed. Is fastened from the outer circumference and fixed to the circumferential grooves 103a and 105a.

The peripheral grooves 103a of the retainers 103 and 105,
On the inner peripheral side of 105a, there are formed restraint portions 116 and 117 for gradually narrowing the radial width of the circumferential grooves 103a and 105a toward the mutually opposing end surface sides of the retainers 103 and 105. On the other hand, on the inner peripheral surfaces of the sliding rings 101 and 102,
Corresponding to the tapered outer peripheral surfaces of the restraint portions 116 and 117, tapered surfaces are formed that gradually narrow the radial widths of both sliding rings 101 and 102 toward the sealing sliding surface S side. By fitting with the restraining portions 116 and 117, the sliding rings 101 and 102 can move to the circumferential grooves 103a and 1
The axial disengagement from 05a is prevented.

On the end face of the seal case 13 of the housing 1 on the retainer 103 side, for example, cutouts 118 are formed at two positions in the circumferential direction at the divided portion thereof, and also on the end face of the collar 106 on the retainer 105 side. Similarly, cutouts 119 are formed at two locations in the circumferential direction at the divided portions. Further, the protruding pieces 103b of the stationary side retainer 103, which are coupled to each other, are housed in the notches 118 of the seal case 13 in a loosely fitted state, and the protruding pieces 105b of the rotating side retainer 105 are notched by the notches of the collar 106. Part 11
It is accommodated in 9 in a loosely fitted state. Further, as shown in FIG. 2, the protruding piece 103 b of the stationary side retainer 103 and the notch 118 of the seal case 13 are in contact with each other in the planes extending in the radial direction, and the protruding piece 105 b of the rotating side retainer 105 is in contact with each other. The same applies to the cutout 119 of the collar 106.

A plurality of holes (not shown) are formed at equal intervals in the circumferential direction on the end surface of the seal case 13 of the housing 1 facing the stationary side retainer 103, and coil springs (not shown) are formed in the holes. ) Is held. The stationary side retainer 103 is axially pressed and urged by the coil spring, and the stationary side sliding ring 10 is
By being urged in the axial direction through the stationary side retainer 103, the rotating side sliding ring 102 and the opposing end surfaces thereof come into close contact with each other to perform sealed sliding.

In this embodiment, the stationary side retainer 10
The protruding piece 103b of No. 3 is a retainer piece 103 having a semicircular arc shape.
The stationary side retainer 103 is a connecting portion for connecting A and 103B in an annular shape via the fastening member 108, and is housed in the notch 118 formed in the seal case 13 of the housing 1 in a loosely fitted state. Has a function as a rotation stopping means for maintaining the non-rotating state. Similarly, the protruding piece 105 b of the rotary side retainer 105 is configured such that the retainer 105 has a semi-arcuate retainer piece.
It is a connecting part for connecting in an annular shape through 9, and
By being housed in the notch 119 of the collar 106 fixed to the rotary shaft 2 in a loosely fitted state, the collar 106 has a function as a circumferential engagement means for receiving the rotational force of the collar 106 and integrally rotating. .

Although the fluid in contact with the surface of the collar 106, the retainer 105, the holder 113, etc. on the rotating side is unavoidably rotated, the protrusion 105b of the rotating side retainer 105 has a cutout portion of the collar 106. 119
Since it is housed in the above, the stirring action of the fluid due to the impeller action of the protrusion 105b hardly occurs. Therefore, the pressing force that acts on the abutting surface between the protrusion 105b and the cutout portion 119 due to the fluid resistance is reduced, and the flow velocity of the fluid in the rotation direction is also suppressed. Further, since the protruding piece 103b of the stationary side retainer 103 is accommodated in the notch 118 of the seal case 13 in a loosely fitted state, the rotationally flowing fluid is less likely to collide with the protruding piece 103b, and the protruding piece 103b is first As mentioned above, since the flow velocity of the fluid is low,
The pressing force acting on the abutting surface between the protruding piece 103b and the notch 118 is reduced.

The stationary side sealing member including the sliding ring 101, the retainer 103, the holder 114, etc. is the retainer 10
3 is axially movably supported by the seal case 13 of the housing 1 and is pressed in the axial direction (right side in the drawing) by the spring, so that the rotational axis 2 is displaced in the axial direction during driving. Accordingly, the sliding ring 102,
With respect to the axial displacement of the rotary side sealing member including the retainer 105, the holder 113, the collar 106 and the like, the sliding surface S is axially moved so that the sliding surface S always comes into sliding contact with an appropriate contact pressure. Therefore, the protruding piece 103b of the stationary side retainer 103
Is rubbed with the notch 118 of the seal case 13 by the axial follow-up operation, but since the projection 103b and the notch 118 are abutted with each other in the planes extending in the radial direction, they are brought into contact with each other. The pressure is small, and the progress of wear of the abutting surface is effectively reduced.

Further, the protrusions 103b and 105b are formed in the cutout portion 1.
Since it is housed in the protrusions 18 and 119, heat exchange with the fluid is not concentrated in the protrusions 103b and 105b. Therefore, the retainers 103, 1
It is possible to prevent the occurrence of a gap between the sliding surfaces S of the sliding rings 101 and 102 and the local increase of the contact pressure of the sliding surfaces S due to the thermal strain due to the temperature difference in the circumferential direction of 05.

In the above embodiment, the sliding rings 101, 102, the retainers 103, 105, the collar 1 are used.
06, the holders 112, 113 and the like are described as being divided into two in the circumferential direction, but the number of divisions is not particularly limited.

[0022]

According to the present invention, since the projections for connecting the arcuate pieces of the retainer to each other also serve as the circumferential engaging means with the stationary housing or the rotating collar, the engaging means. It is not necessary to separately provide pins and the like. Further, since the projecting piece is housed in the notch formed in the housing and the collar, the power loss due to the fluid resistance due to the stirring action of the projecting piece of the rotating side retainer and the fluid flowing to the projecting piece of the stationary side retainer. Since the pressing force of the protrusion and the notch due to the collision of the abutment is reduced and wear of the abutment surface is effectively suppressed, the stationary side composed of the stationary side retainer and the stationary side sliding ring held by the stationary side retainer. The axial followability of the sealing member is maintained well. Moreover, thermal strain due to the temperature difference in the circumferential direction of the retainer is also prevented. Therefore, it is possible to improve the sealing performance between the sliding surfaces of the stationary and rotating sliding rings and prevent abnormal wear of the sliding surfaces.

[Brief description of drawings]

FIG. 1 is a half sectional view showing a preferred embodiment of a shaft sealing device according to the present invention by cutting along a plane passing through an axis.

FIG. 2 is a partial cross-sectional view of the stationary side retainer in the above embodiment, taken along a plane orthogonal to the axis.

FIG. 3 is a half sectional view showing an example of a conventional shaft sealing device, taken along a plane passing through an axis.

[Explanation of symbols]

 1 Housing 2 Rotating Shaft 10 Shaft Sealing Device 101, 102 Sliding Ring 103, 105 Retainer 103a, 105a Circumferential Groove 103A, 103B Retainer Fragment 106 Collar 103b, 105b Projecting Piece 118, 119 Notch

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Taizo Inagaki 2-4 Suehiro-cho, Tsurumi-ku, Yokohama-shi, Kanagawa Toshiba Keihin Office (72) Inventor Toru Sogabe 1500 Katayanagi, Sakado, Saitama Prefecture Eagle Industry Co., Ltd. Saitama Factory (72) Inventor Hiroshi Aoike 1500 Katayanagi, Sakado City, Saitama Prefecture Eagle Industry Co., Ltd. Saitama Factory

Claims (2)

[Claims] 1. A pair of sliding rings which are divided at a plurality of positions in the circumferential direction and which are annularly assembled and slidably contact each other at their axially opposed end faces, and a plurality of positions are divided at a plurality of positions in the circumferential direction. And a pair of retainers respectively arranged on the stationary side and the rotating side in a state of being coupled to each other in an annular shape, wherein each of the sliding rings is formed to extend in the circumferential direction on the mutually opposing end surfaces of each of the retainers. In the shaft sealing device held in the circumferential groove, the arcuate pieces of the retainer are joined by the projecting pieces formed on both ends in the circumferential direction of the retainer, and the projecting piece of the retainer on the stationary side is the housing on the stationary side. A shaft sealing device characterized in that it is engaged with a notch portion formed in the circumferential direction, and the protrusion of the retainer on the rotation side is engaged with the notch portion formed on the rotation side collar in the circumferential direction. . 2. The shaft sealing device according to claim 1, wherein each of the projecting pieces is in flat contact with the inner surface of each of the cutouts.