JP2018179080A - Shaft seal device, rotary machine, and maintenance method of shaft seal device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a shaft seal device which can prevent leakage of a lubrication oil.SOLUTION: A shaft seal device 50 includes: a rotary member 56 which may be attached to a rotary shaft 1; and a cover 57 which is disposed facing the rotary member 56. The rotary member 56 includes: a cylindrical part 60 which is partially positioned in an external space opposite to an internal space, in which a bearing is disposed, with respect to the cover 57; and a flange part 61 extending to the radial outer side of the cylindrical part 60 and positioned in the internal space. A radial gap G1 extending in an axial direction of the cylindrical part 60 is formed between the cylindrical part 60 and the cover 57, and an axial gap G2 extending to the radial outer side of the cylindrical part 60 is formed between the flange part 61 and the cover 57.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a shaft seal device, a rotary machine provided with the shaft seal device, and a method of maintaining the shaft seal device.

  A pump is a rotary machine that pumps a liquid such as water by rotating an impeller disposed in a casing. The pump generally comprises a casing having an inlet and an outlet, an impeller disposed inside the casing, and a rotary shaft to which the impeller is fixed. When the impeller rotates with the rotation shaft, liquid is drawn from the suction port of the casing. The liquid is pressurized in the casing as the impeller rotates, and discharged from the discharge port.

  The rotating shaft is rotatably supported by a bearing. The bearing is contained within a bearing housing provided adjacent to the casing. In the bearing housing, lubricating oil for lubricating and cooling the bearing is stored, and the lower part of the bearing is immersed in the lubricating oil. As the inner ring of the bearing rotates, lubricating oil is supplied to the entire bearing.

Japanese Patent Application Laid-Open No. 60-247097 Japanese Utility Model Application Publication No. 63-150099

  Since the rotating shaft extends through the bearing housing, a clearance necessarily exists between the outer peripheral surface of the rotating shaft and the bearing housing. Therefore, in order to prevent the leakage of the lubricating oil from the gap, a contact type seal such as an oil seal is provided between the outer peripheral surface of the rotating shaft and the bearing housing. However, such a contact type seal is in sliding contact with the outer peripheral surface of the rotating shaft and gradually wears out. The worn seal can not properly seal the gap between the outer circumferential surface of the rotating shaft and the bearing housing, and the lubricating oil may leak.

  As another technique, it is conceivable to provide a noncontact seal such as a labyrinth seal between the outer peripheral surface of the rotating shaft and the bearing housing. However, in this case, it is essential to adjust the position of the noncontact seal in order to obtain a predetermined sealing performance.

The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a shaft seal device capable of preventing the leakage of lubricating oil.
Another object of the present invention is to provide a pump provided with the shaft seal device.
Another object of the present invention is to provide a maintenance method of the shaft seal device.

  One aspect is a shaft seal device for preventing leakage of lubricating oil supplied to a bearing, comprising: a rotating member mountable to a rotating shaft; and a cover disposed opposite to the rotating member. The rotating member has a cylindrical portion located in an external space on the side opposite to the internal space in which the bearing is disposed with respect to the cover, and a flange extending radially outward of the cylindrical portion and located in the internal space And a radial gap extending in the axial direction of the cylindrical portion is formed between the cylindrical portion and the cover, and the cylindrical portion is formed between the flange portion and the cover. An axial sealing device is characterized in that an axial gap extending radially outward of the part is formed.

A preferable aspect is characterized in that a fixed side flow passage is formed on the surface of the cover facing the flange portion.
A preferable aspect is characterized in that a rotation side flow passage is formed on the surface of the flange portion facing the cover.
A preferred embodiment is characterized by comprising a seal member disposed between the rotating member and the cover.

A preferred embodiment further comprises a ring member fixable to the cylindrical portion, wherein the ring member is disposed in the external space.
A preferred embodiment is characterized in that the cylindrical portion is provided with a fastening hole extending from the outer peripheral surface toward the inner peripheral surface, and the fastening hole is disposed in the outer space.

  Another aspect comprises an impeller, a rotating shaft to which the impeller is fixed, a bearing that rotatably supports the rotating shaft, a bearing housing that accommodates the bearing, and the shaft sealing device. It is a rotating machine characterized by

  Yet another aspect is the maintenance method of the shaft seal device, wherein the rotating member is moved in a direction in which the flange portion approaches the cover until the flange portion contacts the cover, and the flange portion is moved With the cover in contact, the reference position of the rotary member is determined, and the rotary member is moved from the reference position by a predetermined distance in the direction in which the flange part is separated from the cover, and The axial gap is formed between the cover and the cover.

  According to the present invention, the rotating member can be easily moved in the axial direction. Therefore, the size of the gap between the flange portion and the cover can be easily adjusted, and as a result, the leakage of the lubricating oil can be prevented.

It is a sectional view showing a pump provided with one embodiment of a shaft seal device. FIG. 2 is an enlarged cross-sectional view of the bearing assembly shown in FIG. It is a figure showing one embodiment of a shaft seal device. FIG. 5 is a view showing the flow of air and the flow of lubricating oil inside a bearing assembly. It is the figure which looked at the cover from the external space side. It is a figure which shows the clearance gap formed between the rotation member and the cover. It is a figure which shows the procedure which adjusts the clearance gap of a shaft sealing apparatus. It is a figure which shows the procedure which adjusts the clearance gap of a shaft sealing apparatus. It is a figure which shows the procedure which adjusts the clearance gap of a shaft sealing apparatus. It is a figure which shows the procedure which adjusts the clearance gap of a shaft sealing apparatus. It is a figure which shows the other procedure which adjusts the clearance gap of a shaft sealing apparatus. It is a figure for demonstrating the advantage which provides a shaft sealing apparatus. It is a sectional view showing other embodiments of a shaft seal device. It is sectional drawing which shows the cover shown in FIG. It is the figure which looked at the cover of FIG. 14 from the A line direction. It is a top view of the rotation member of FIG. It is a figure which shows the further another embodiment of a shaft sealing apparatus.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the embodiments described below, a pump as an example of a rotary machine will be described, but the rotary machine is not limited to the pump. As another example of a rotary machine, a water wheel, a compressor, a blower, etc. can be mentioned.

  FIG. 1 is a cross-sectional view showing a pump provided with an embodiment of a shaft seal device. The pump as a rotary machine shown in FIG. 1 is a land horizontal axis pump (horizontal axis single-stage centrifugal pump). The pump includes an impeller 2 and a rotating shaft 1 to which the impeller 2 is fixed. The rotation axis 1 extends horizontally. One end of the rotary shaft 1 is connected to a drive such as an electric motor (not shown), and the rotary shaft 1 and the impeller 2 are rotated by this drive. The rotating shaft 1 is supported by a bearing assembly 9.

  The impeller 2 is disposed in the casing 5. The casing 5 has a swirl chamber 5a therein, and the impeller 2 is disposed in the swirl chamber 5a. When the impeller 2 rotates with the rotating shaft 1, a liquid such as water is sucked from the suction port 3, the pressure of the liquid is increased by the action of the impeller 2 and the swirl chamber 5 a, and the liquid is discharged from the discharge port 4. A gap between the rotary shaft 1 and the casing 5 is sealed by a shaft seal 11 such as a mechanical seal. The shaft seal 11 can prevent the liquid in the casing 5 from leaking from the gap between the casing 5 and the rotating shaft 1.

  FIG. 2 is an enlarged sectional view of the bearing assembly 9 shown in FIG. As shown in FIG. 2, the bearing assembly 9 includes bearings 9A and 9B for rotatably supporting the rotating shaft 1, and a bearing housing 36 in which the bearings 9A and 9B are accommodated. In the present embodiment, the bearing 9A is a cylindrical roller bearing, and the bearing 9B is an angular ball bearing. Lubricant oil is stored inside the bearing assembly 9. The liquid level of the lubricating oil is located below the rotary shaft 1.

  The bearing 9A is mounted on the bearing housing 36, and an outer ring 30A movable in the axial direction, an inner ring 31A fixed to the outer peripheral surface of the rotary shaft 1, and rolling elements 33 disposed between the outer ring 30A and the inner ring 31A. And have.

  The bearing 9B includes an outer ring 30B fixed to the bearing housing 36, an inner ring 31B fixed to the outer peripheral surface of the rotary shaft 1, and rolling elements 32 disposed between the outer ring 30B and the inner ring 31B. When the inner rings 31A and 31B rotate with the rotation shaft 1, the rolling elements of the bearings 9A and 9B rotate between the outer rings 30A and 30B and the inner rings 31A and 31B. The lower part of the bearings 9A, 9B is immersed in lubricating oil. Therefore, when the inner rings 31A, 31B rotate with the rotary shaft 1, the lubricating oil is supplied to the entire bearings 9A, 9B.

  Part of the lubricating oil supplied to the bearings 9A, 9B passes through the bearings 9A, 9B and flows to the outside of the bearings 9A, 9B. Therefore, the bearing assembly 9 is provided with shaft seal devices 50, 50 for preventing the lubricating oil from leaking from between the bearing housing 36 and the rotary shaft 1. The shaft seal devices 50, 50 are respectively adjacent to the bearings 9A, 9B, and can prevent the leakage of the lubricating oil supplied to the bearings 9A, 9B. Since these two shaft sealing devices 50, 50 have the same configuration, hereinafter, the shaft sealing device 50 disposed adjacent to the bearing 9B will be described with reference to the drawings.

  FIG. 3 is a view showing an embodiment of the shaft seal device 50. As shown in FIG. The shaft sealing device 50 includes an annular rotating member 56 that can be attached (fixed) to the rotating shaft 1 and an annular cover 57 disposed opposite to the rotating member 56. The rotating member 56 may be called a sleeve or a sleeve for oil sealing, and the cover 57 may be called a bearing cover or a fixing member (stationary member).

  As shown in FIG. 3, the rotary member 56 is disposed concentrically with the rotary shaft 1, and the rotary member 56 mounted on the rotary shaft 1 can rotate integrally with the rotary shaft 1. The rotating member 56 includes a cylindrical portion 60 extending in parallel to the axial direction of the rotating shaft 1 and a flange portion 61 extending outward from the cylindrical portion 60. A portion of the cylindrical portion 60 is located in an outer space opposite to the inner space in which the bearings 9A and 9B are disposed with respect to the cover 57. In other words, a part of the cylindrical portion 60 protrudes from the cover 57 and is located outside the cover 57. The flange portion 61 extends outward in the radial direction of the cylindrical portion 60 and is located in the inner space. In other words, the flange portion 61 is located inside the cover 57.

  Here, the internal space is a space SP1 (see FIG. 1) formed by the bearing housing 36 and the cover 57, and the bearings 9A, 9B and the flange portion 61 of the rotating member 56 are disposed in the internal space SP1. . The external space is space SP2, SP3 (see FIG. 1) formed on the opposite side of the internal space SP1. In the present embodiment, as shown in FIG. 1, the external space is a space outside the internal space SP1 formed by the bearing housing 36 and the cover 57, that is, a space SP2 surrounding the entire pump, and the shaft seal seal 11 Is a space including the space SP3 in which the

  As shown in FIG. 3, the flange portion 61 is connected to the outer peripheral surface 60 a of the cylindrical portion 60 and protrudes in a direction away from the outer peripheral surface 60 a of the cylindrical portion 60. In the present embodiment, the cylindrical portion 60 and the flange portion 61 are integrally formed members. In one embodiment, the cylindrical portion 60 and the flange portion 61 may be separate members. Furthermore, in the present embodiment, the flange portion 61 is connected to the inner end surface 60b of the cylindrical portion 60. However, in one embodiment, the flange portion 61 does not necessarily have to be the inner end surface 60b if disposed in the internal space SP1. It does not have to be connected.

  Here, the inner end surface 60b of the cylindrical portion 60 is the end surface of the cylindrical portion 60 located in the internal space SP1, and the outer end surface 60c of the cylindrical portion 60 is the end surface of the cylindrical portion 60 located in the external space SP2.

  The flange portion 61 has a first surface 61 a facing the first surface 57 b of the cover 57 and a second surface 61 b opposite to the first surface 61 a. The first surface 57b of the cover 57 constitutes a part of the internal space SP1, and the second surface 57c is disposed on the opposite side of the first surface 57b. The second surface 57c of the cover 57 is located in the external space SP2.

  As shown in FIG. 3, an annular seal member 65 is disposed between the cylindrical portion 60 and the cover 57. In the present embodiment, the seal member 65 is a contact seal such as an oil seal, and is mounted on an annular step 57d formed between the through hole 57a of the cover 57 and the first surface 57b. In one embodiment, the seal member 65 may be a noncontact seal such as a labyrinth seal provided between the outer peripheral surface 60 a of the cylindrical portion 60 and the through hole 57 a of the cover 57. In another embodiment, the seal member 65 may be a combination of contact and non-contact seals. The seal member 65 is disposed inside the bearing assembly 9 and located in the internal space SP1.

  An upper groove 70 is formed in the upper portion of the cover 57, and a lower groove 71 is formed in the lower portion of the cover 57. The grooves 70 and 71 are formed in the first surface 57b. The upper groove 70 is disposed above the seal member 65, and the lower groove 71 is disposed below the seal member 65.

  The reason for providing the upper groove 70 is as follows. That is, when the upper groove 70 is not provided, the space formed by the bearing 9B, the bearing housing 36, and the cover 57 is sealed, and the flow of the lubricating oil is hindered. The upper groove 70 is provided to allow lubricating oil to flow smoothly, and serves as air removal.

  An annular groove 72 is formed between the upper groove 70 and the lower groove 71. The annular groove 72 is connected to both the upper groove 70 and the lower groove 71, and is disposed concentrically with the rotation shaft 1 and the rotation member 56. The lubricating oil in the annular groove 72 flows down the annular groove 72 by the action of gravity, and then the lubricating oil is returned to the bearing housing 36.

  FIG. 4 is a view showing the flow of air inside the bearing assembly 9 and the flow of lubricating oil. As shown in FIG. 4, the flow of air inside the bearing assembly 9 (see arrow AR1 in FIG. 4) is formed above the lubricating oil, and the air in the bearing housing 36 is directed toward the above space. Flow. As shown by arrow AR2 in FIG. 4, the lubricating oil in the space flows toward the bearing housing 36.

  FIG. 5 is a view of the cover 57 as viewed from the external space SP2 side. As shown in FIG. 5, the outer shape of the cover 57 has a rounded rectangular shape, and a plurality of fasteners (not shown) such as screws are inserted into the four corners of the cover 57 (this embodiment) In the above, four insertion holes 59 are formed. Therefore, the cover 57 fixed to the bearing housing 36 does not rotate integrally with the rotating shaft 1 and the rotating member 56. In one embodiment, the outer shape of the cover 57 may have a circular shape, and the number of insertion holes 59 is not limited to this embodiment.

  The cover 57 is fluidly fastened to the bearing housing 36 by fasteners (not shown). More specifically, as shown in FIG. 3, a gasket 58 is disposed between the cover 57 and the bearing housing 36. The gasket 58 is sandwiched between the cover 57 and the bearing housing 36, and the fastener brings the cover 57 into close contact with the bearing housing 36 via the gasket 58. In this way, it is possible to prevent the infiltration and leakage of liquid from between the cover 57 and the bearing housing 36. The gasket 58 is also disposed between the cover 57 disposed adjacent to the bearing 9A and the bearing housing 36 (see FIGS. 1 and 2).

  In the present embodiment, the cover 57 and the bearing housing 36 are separate members, but any one of the cover 57 adjacent to the external space SP2 and the cover 57 adjacent to the external space SP3 and the bearing housing 36 are integrally formed members. It may be.

  By fastening the cover 57 and the bearing housing 36 through the gasket 58, the cover 57 can close the open end of the bearing housing 36, and as a result, the lubricating oil in the internal space SP1 and the bearing housing 36 It does not leak from between the cover 57. The rotation shaft 1 extends through a through hole 57 a formed at the center of the cover 57. The through hole 57 a of the cover 57 is disposed concentrically with the rotary shaft 1 and the rotary member 56. A portion of the cylindrical portion 60 is disposed inside the through hole 57 a of the cover 57. The through hole 57a of the cover 57 is disposed between the first surface 57b and the second surface 57c, and is connected to the surfaces 57b and 57c.

  The cylindrical portion 60 is provided with a plurality of fastening holes 66 (see FIG. 3) extending from the outer peripheral surface 60a toward the inner peripheral surface 60d. The plurality of fastening holes 66 are disposed along the circumferential direction of the cylindrical portion 60, and are disposed in the external space SP2. A plurality of fasteners 67 such as screws are respectively inserted into the plurality of fastening holes 66. In the cylindrical portion 60, at least one fastening hole 66 may be formed. The rotating member 56 is fixed to the rotating shaft 1 by tightening the fastener 67. In the present embodiment, the fastener 67 is a set screw.

  The cylindrical portion 60 has an inner circumferential surface 60 d formed on the opposite side of the outer circumferential surface 60 a. The inner circumferential surface 60 d is a surface facing the outer circumferential surface of the rotating shaft 1. In order to prevent the leakage of lubricating oil from a minute gap between the outer peripheral surface of the rotating shaft 1 and the inner peripheral surface 60 d of the cylindrical portion 60, an O-ring or the like may be formed between the rotating shaft 1 and the cylindrical portion 60. A seal member 69 is disposed. The seal member 69 has an annular shape, and is disposed in a seal groove 68 formed in the inner peripheral surface 60 d of the cylindrical portion 60. The sealing member 69 can also prevent the infiltration of liquid from the outside. In one embodiment, more than one sealing member 69 may be provided.

  FIG. 6 is a view showing a gap formed between the rotation member 56 and the cover 57. As shown in FIG. In FIG. 6, a part of the shaft seal device 50 is illustrated. As shown in FIG. 6, gaps G <b> 1 and G <b> 2 are formed between the rotating member 56 and the cover 57. The gap G1 is a radial gap formed between the through hole 57a of the cover 57 and the outer peripheral surface 60a of the cylindrical portion 60. The radial gap G <b> 1 extends cylindrically in the axial direction of the cylindrical portion 60. The gap G2 is an axial gap formed between the first surface 57b of the cover 57 and the first surface 61a of the flange portion 61. The axial gap G 2 annularly extends radially outward of the cylindrical portion 60 and is parallel to the flange portion 61. Hereinafter, in the present specification, the radial gap G1 may be simply referred to as the gap G1, and the axial gap G2 may be simply referred to as the gap G2.

  The gap G1 between the cylindrical portion 60 and the cover 57 is preferably as small as possible without causing contact with each other. Similarly, the gap G2 between the flange portion 61 and the cover 57 is preferably as small as possible without coming in contact with each other. The gaps G1 and G2 are connected via the seal member 65.

  In one embodiment, the size of the gaps G1 and G2 can be determined within the range of 0.01 mm to 1.0 mm. By determining the sizes of the gaps G1 and G2 within such a range, it is possible to suppress the entry of lubricating oil into the gaps G1 and G2, and the rotary member 56 does not contact the cover 57.

  At least one of the rotating member 56 and the cover 57 may be made of non-spark material. The other may be made of, for example, cast iron, cast steel, carbon steel or stainless steel. Both the rotating member 56 and the cover 57 may be made of non-spark material. By employing the non-spark material, it is possible to prevent the occurrence of sparks even when the rotating member 56 in contact with the cover 57. Brass and aluminum can be mentioned as an example of a non-spark material. In one embodiment, a portion that may come into contact with the rotation member 56, for example, a portion of the first surface 57b of the cover 57 may be made of a non-spark material.

  According to the present embodiment, when the rotary shaft 1 is rotated by the driving machine, the lubricating oil entering the gap G2 is blown outward in the radial direction of the flange portion 61 by the centrifugal force generated by the rotation of the rotary member 56. . Therefore, the lubricating oil does not leak through the gap G2 to the external space SP2 (and the external space SP3). Furthermore, the gap G2 is formed in the internal space SP1. Therefore, the lubricating oil does not scatter in the external space SP2 (and the external space SP3), and as a result, the structure for recovering the lubricating oil can be eliminated and the entire pump can be made compact. .

  When the rotating shaft 1 is not rotating, the lubricating oil flows down to the lower part of the cover 57 by the action of gravity, and as a result, is returned to the bearing housing 36. Therefore, the lubricating oil does not leak to the external space SP2 (and the external space SP3). Furthermore, since the seal member 65 is disposed between the rotary member 56 and the cover 57, the seal member 65 can prevent the lubricating oil from passing through the gap G1 when the rotary shaft 1 is not rotating. it can. In the case where the seal member 65 is a contact seal such as an oil seal, the service life of the seal member 65 can be extended by the contact of the lubricating oil entering from the gap G2 with the seal member 65.

  In order to suppress the entry of lubricating oil into the gap G2, it is necessary to appropriately manage the size of the gap G2. According to the present embodiment, since a part of the cylindrical portion 60 is located in the external space SP2 (and the external space SP3), the operator can easily move the rotary member 56 in the axial direction from the outside of the internal space SP1. It can be done. Therefore, the size of the gap G2 between the cover 57 and the flange portion 61 can be easily adjusted by the movement of the rotating member 56. As a result, the size of the gap G2 can be appropriately managed, and the entry of lubricating oil into the gap G2 can be suppressed.

  A method of adjusting the gap G2 of the shaft seal device 50 will be described with reference to the drawings. 7 to 10 are diagrams showing a procedure of adjusting the gap G2 of the shaft sealing device 50. FIG. 7 to 10 show the axis line AX of the rotation axis 1.

  There may be a play (end play) of about 0.1 mm in the axial direction (direction of the axis AX) on the rotation shaft 1. In this case, first, the rotary shaft 1 is moved in the arrow direction of FIG. 7 and the rotary shaft 1 is positioned at a predetermined end position (procedure 1). At this time, the rotary member 56 is not fixed to the rotary shaft 1 and can move in the axial direction of the rotary shaft 1.

  Then, the rotary member 56 is moved in the direction of the arrow in FIG. 8, that is, in the direction in which the flange portion 61 approaches the cover 57, and the first surface 61a of the flange portion 61 of the rotary member 56 is made the first surface 57b of the cover 57. Contact (Procedure 2). In this state, the relative position between the outer end face 60c of the cylindrical portion 60 and the rotary shaft 1, that is, the reference position of the rotary member 56 is determined. More specifically, as shown in FIG. 9, the marking line ML is attached to the rotation axis 1 (procedure 3). The marking line ML is a line segment in the same plane as the outer end surface 60 c of the cylindrical portion 60. The means for attaching the marking line ML is not particularly limited.

  Next, as shown in FIG. 10, the rotary member 56 is moved in the arrow direction of FIG. 10, that is, in the direction in which the flange portion 61 is separated from the cover 57 by a predetermined distance G2 ′ from the position on the marking line ML (Procedure 4) ). The predetermined distance G2 'is a distance corresponding to the above-described gap G2 (G2 = G2'). After the gap G2 is determined, the rotating member 56 is fixed to the rotating shaft 1 by inserting and fastening the fastener 67 in the fastening hole 66 formed in the cylindrical portion 60 (procedure 5).

  Since a part of the cylindrical portion 60 of the rotary member 56 is located in the external spaces SP2 and SP3, the rotary member 56 can be easily moved in the axial direction of the rotary shaft 1 in the external spaces SP2 and SP3. Therefore, the size of the gap G2 can be easily and quickly determined without disassembling the bearing assembly 9. Furthermore, according to the present embodiment, even if the rotary member 56 rotates, the contact of the rotary member 56 with the cover 57 can be reliably prevented. As a result, it is possible to reliably prevent the powder generated by the contact between the rotary member 56 and the cover 57 from being mixed with the lubricating oil.

  Furthermore, according to the present embodiment, the size of the gap G2 is limited even if the seal member 65 can not sufficiently exhibit its function due to the use of the seal member 65 for a long period of time, etc. It is possible to prevent a large amount of lubricating oil from leaking. Therefore, the pump can be operated even before the replacement of the seal member 65.

  Furthermore, according to the present embodiment, the number of parts of the shaft sealing device 50 can be reduced, and the shape of the shaft sealing device 50 can be simplified, so that the price of the shaft sealing device 50 can be reduced. The axial length of the shaft seal device 50 can be reduced.

  Since the rotating member 56 and the cover 57 are formed as separate members, even if the rotating member 56 is worn, only the rotating member 56 may be replaced. It is also possible to apply a coating to the rotating member 56 to reduce wear.

  FIG. 11 is a view showing another procedure for adjusting the gap G2 of the shaft seal device 50. As shown in FIG. As shown in FIG. 11, the jig 82 includes a positioning member 83 capable of contacting both the rotary shaft 1 and the rotary member 56, and a shim 84 disposed between the positioning member 83 and the rotary member 56. ing. The positioning member 83 basically includes a bottom portion 83a and a cylindrical insertion portion 83b, and the insertion portion 83b is connected to the bottom portion 83a. The shim 84 is composed of a plurality of shim parts having different thicknesses. For example, the thicknesses of the plurality of shim parts are 0.02 mm, 0.05 mm, 0.1 mm, 0.2 mm, and 0.5 mm, respectively.

  The thickness of the shim parts is not limited to the embodiment described above, and the user can select shim parts having any thickness. Furthermore, depending on the configuration of the positioning member 83, the shim 84 itself may be unnecessary.

  A method of determining the gap G2 of the shaft sealing device 50 using the jig 82 will be described. After the rotary member 56 is in close contact with the cover 57 (see FIG. 8), the jig 82 including the positioning member 83 and the shim 84 is moved in the direction of the arrow in FIG. The shim 84 is brought into contact with the outer end face 60 c of the cylindrical portion 60, and the bottom 83 a of the positioning member 83 is brought into contact with the end face 1 a of the rotary shaft 1. Thus, the relative position between the outer end face 60c of the cylindrical portion 60 and the rotation shaft 1, that is, the reference position of the rotating member 56 is determined. At this time, the number of shim parts may be adjusted. In one embodiment, each shim part has a split shape and can be disassembled, so the number of shim parts can be reduced or increased.

  With the bottom 83a of the positioning member 83 in contact with the end face 1a of the rotary shaft 1, an adjustment shim (not shown) having a thickness (for example, 0.1 mm) corresponding to the gap G2 is a shim 84 (or positioning member 83) And the cylindrical portion 60. As a result, the rotary member 56 moves away from the cover 57 by the thickness of the adjustment shim. Thus, the gap G2 can be formed between the flange portion 61 and the cover 57.

  Next, an example of the advantage of providing the shaft seal device 50 will be described with reference to the drawings. FIG. 12 is a view for explaining the advantage of providing the shaft seal device 50. As shown in FIG. In FIG. 12, the shaft seal device 50 according to the present embodiment is drawn on the upper side of the axis line AX of the rotation shaft 1, and the configuration as a comparative example is drawn on the lower side. In FIG. 12, reference numerals are attached to the configuration necessary to explain the advantages.

  The ratio (B '/ A') of the distance A 'from the center of the bearing 9A to the center of the bearing 9A and the distance B' from the center of the discharge port 4 to the center of the bearing 9B on the upper side of FIG. It is called the overhang ratio. In the lower half of FIG. 12, the ratio (B / A) of the distance B from the center of the outlet 4 to the center of the bearing 9B and the distance A from the center of the bearing 9A to the center of the bearing 9B is the second overhang ratio It is called.

  The total length of the pump may be standardized. The smaller the overhang ratio over the entire length of the standardized pump, the smaller the pump vibration tends to be, and the life of the bearings 9A and 9B can be extended. According to the present embodiment, since the shaft sealing device 50 has a compact structure, the distance between the shaft sealing device 50 and the end of the pump can be reduced, and as a result, the first The overhang ratio (B '/ A') can be smaller than the second overhang ratio (B / A). On the other hand, since the shaft sealing device of the comparative example has a complicated structure, the axial length of the rotating shaft 1 must be increased, and as a result, the second overhang ratio (B / A) becomes large. According to the present embodiment, since the first overhang ratio (B '/ A') is smaller than the second overhang ratio (B / A), the vibration of the pump can be reduced. The life of 9B can be extended.

  FIG. 13 is a cross-sectional view showing another embodiment of the shaft seal device 50. As shown in FIG. In FIG. 13, the upper half of the shaft sealing device 50 is illustrated. FIG. 14 is a cross-sectional view showing the cover 57 shown in FIG. FIG. 15 is a view of the cover 57 of FIG. FIG. 16 is a plan view of the rotating member 56 of FIG. The configuration and operation of the present embodiment, which are not particularly described, are the same as those of the above-described embodiment, and thus redundant description will be omitted.

  A flow path (fixed side flow path) 73 including an annular flow path 73 a and a linear flow path 73 b connected to the annular flow path 73 a is formed on the inner side in the radial direction of the annular groove 72. The annular channel 73 a is disposed concentrically with the rotary shaft 1, the rotary member 56, and the annular groove 72, and is disposed between the through hole 57 a of the cover 57 and the annular groove 72.

  The straight flow passage 73b is connected to the lowermost portion of the annular flow passage 73a. The straight flow path 73 b is disposed on the center line CL of the cover 57. The straight channel 73 b is also connected to the annular groove 72. More specifically, the upper end of the linear flow path 73b is connected to the annular flow path 73a, the lower end is connected to the annular groove 72, and the annular flow path 73a and the annular groove 72 communicate with each other through the linear flow path 73b doing. The lubricating oil in the annular flow passage 73a flows down the annular flow passage 73a and the linear flow passage 73b by the action of gravity. The lubricating oil is then returned to the bearing housing 36.

  As shown in FIG. 13 and FIG. 16, the first surface 61 a of the flange portion 61 includes an annular channel 75 a and a radial channel 75 b connected to the annular channel 75 a (rotation Side channel) 75 is formed. The annular flow passage 75 a is disposed concentrically with the rotation shaft 1 and the cylindrical portion 60. The plurality of radiation channels 75 b extend radially outward of the annular channel 75 a. In the present embodiment, four radiation channels 75 b are formed, but the number of radiation channels 75 b is not limited to this embodiment.

  When the rotating member 56 is not rotating, the lubricating oil flowing into the annular flow channel 75a flows down the annular flow channel 75a by the action of gravity and rotates through the radiation flow channel 75b located at the lower part of the annular flow channel 75a. It falls below the member 56. The lubricating oil is then returned to the bearing housing 36.

  When the rotating member 56 is rotating, the lubricating oil flowing into the annular flow passage 75a is pressed against the first surface 61a forming the annular flow passage 75a by the centrifugal force generated by the rotation of the rotating member 56. At least a portion of the lubricating oil is blown radially outward of the flange portion 61 through the radial flow path 75b.

  The flow path 73 is formed on the first surface 57 b of the cover 57, and the flow path 75 is formed on the first surface 61 a of the flange portion 61. Therefore, the flow path 73 and the flow path 75 face each other There is. Accordingly, the lubricating oil flows down through at least one of the flow paths 73 and 75 to the lower part of the cover 57, and as a result, is returned to the bearing housing 36. According to the present embodiment, the formation of the gap G2 makes it possible to suppress the entry of lubricating oil into the gap G2, and a small amount of lubricating oil that has entered the gap G2 is bearing through at least one of the flow paths 73 and 75. It can be returned to the housing 36. Therefore, the lubricating oil is prevented from leaking to the external space SP2 through the gap G2.

  FIG. 17 is a view showing still another embodiment of the shaft seal device 50. As shown in FIG. As shown in FIG. 17, the shaft sealing device 50 may further include a ring member 80 attachable to the cylindrical portion 60 of the rotating member 56. The ring member 80 may be made of an elastic material such as rubber, or may be made of a hard material such as metal. In one embodiment, a ring groove (not shown) may be formed on the outer peripheral surface 60a of the cylindrical portion 60, and the ring member 80 may be fitted into the ring groove.

  The ring member 80 is disposed in the external space SP2, and is mounted (fixed) on the rotation member 56 so as to be rotatable together with the rotation member 56. The cover 57 is disposed between the flange portion 61 and the ring member 80. Since the ring member 80 is separated from the second surface 57 c of the cover 57, the ring member 80 does not contact the cover 57 even when it rotates with the rotation member 56.

  In the present embodiment, the ring member 80 is disposed between the fastening hole 66 of the cylindrical portion 60 and the cover 57, and a minute gap is formed between the ring member 80 and the cover 57. The size of the ring member 80 is not particularly limited, and may be the same as the size of the flange portion 61. In one embodiment, the size of the ring member 80 may be smaller than the size of the flange 61 or may be larger than the size of the flange 61.

  According to the present embodiment, the ring member 80 can prevent foreign matter such as dust and rain existing in the external space SP2 from intruding into the internal space SP1 through the gaps G1 and G2.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to the said embodiment, A various deformation | transformation is possible within the range of the technical idea described in the claim.

DESCRIPTION OF SYMBOLS 1 rotary shaft 1a end face 2 impeller 3 suction port 4 discharge port 5 casing 5a spiral chamber 9 bearing assembly 9A, 9B bearing 11 shaft seal seal 36 bearing housing 50 shaft sealing device 56 rotating member 57 cover 57a through hole 57b first Surface 57c Second surface 57d Annular step 58 Gasket 60 Cylindrical portion 60a Outer peripheral surface 60b Inner end surface 60c Outer end surface 60d Inner peripheral surface 61 Flange portion 61a First surface 61b Second surface 65 Seal member 66 Fastening hole 67 Fasteners 68 seal groove 69 seal member 70 upper groove 71 lower groove 72 annular groove 73 flow path (fixed side flow path)
73a annular channel 73b straight channel 75 channel (rotation side channel)
75a annular flow path 75b radiation flow path 80 ring member 82 jig 83 positioning member 83a bottom 83b insertion portion 84 shim

Claims (8)

A shaft sealing device for preventing leakage of lubricating oil supplied to a bearing, comprising:
A rotating member mountable to the rotating shaft,
And a cover disposed opposite to the rotating member,
The rotating member is
A cylindrical portion located in an external space opposite to the internal space in which the bearing is disposed with respect to the cover in part;
And a flange portion extending radially outward of the cylindrical portion and located in the internal space;
Between the cylindrical portion and the cover, a radial gap extending in the axial direction of the cylindrical portion is formed,
An axial gap is formed between the flange portion and the cover, the axial gap extending outward in the radial direction of the cylindrical portion.   The shaft sealing device according to claim 1, wherein a fixed side flow passage is formed on a surface of the cover facing the flange portion.   The shaft sealing device according to claim 1, wherein a rotation side flow passage is formed on a surface of the flange portion facing the cover.   The shaft sealing device according to claim 1, further comprising a seal member disposed between the rotating member and the cover. It further comprises a ring member fixable to the cylindrical portion,
The shaft seal device according to any one of claims 1 to 4, wherein the ring member is disposed in the external space. The cylindrical portion is provided with a fastening hole extending from its outer peripheral surface toward its inner peripheral surface;
The shaft sealing device according to any one of claims 1 to 5, wherein the fastening hole is disposed in the external space. With the impeller,
A rotating shaft to which the impeller is fixed;
A bearing rotatably supporting the rotating shaft;
A bearing housing for receiving the bearing;
A rotary machine comprising the shaft sealing device according to any one of claims 1 to 6. A maintenance method of the shaft seal device according to any one of claims 1 to 6,
Moving the rotating member in a direction in which the flange portion approaches the cover until the flange portion contacts the cover;
With the flange portion in contact with the cover, the reference position of the rotating member is determined;
The rotational member is moved from the reference position by a predetermined distance in a direction in which the flange portion is separated from the cover, thereby forming the axial gap between the flange portion and the cover. Method.

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