JP2017036762A - Bearing device and rotary machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bearing device which makes abrasion powder less likely to occur even if an oil ring contacts with a structure disposed around the oil ring.SOLUTION: A bearing device 9 includes: bearings 9A, 9B which support an axial load and/or a radial load of a rotary shaft 1; a lubrication oil storage tank 10 disposed below the bearings 9A, 9B; and an oil ring 20 which is supported by the rotary shaft 1 and scrapes the lubrication oil stored in the lubrication oil storage tank 10 as the rotary shaft 1 rotates. Both side surfaces 20A, 20B of the oil ring 20 are formed by a lipophilic material.SELECTED DRAWING: Figure 7

Description

  The present invention relates to a bearing device used in a rotary machine such as a horizontal shaft pump, and more particularly to a bearing device that supplies lubricating oil to a bearing by an oil ring that rotates together with the rotary shaft. The present invention also relates to a rotary machine such as a pump provided with such a bearing device.

  2. Description of the Related Art A horizontal shaft type rotary machine (for example, a horizontal shaft pump) in which a rotary shaft is installed horizontally includes a bearing device that rotatably supports the rotary shaft. As the bearing, a slide bearing and / or a rolling bearing is usually used, and lubricating oil is used as a lubricant for lubricating and cooling such a bearing. Examples of means for supplying lubricating oil to the bearing include a forced oil supply device using external power or a self-lubricating device that does not use external power.

  As for the self-lubricating device, an oil ring type self-lubricating device is known in which the lubricating oil is pumped up by using the rotational force of the oil ring rotating together with the rotating shaft from the lubricating oil storage tank disposed below the rotating shaft inside the bearing device. (See Patent Document 1 and Patent Document 2). Lubricating oil pumped up by the oil ring is supplied to the bearing. The oil ring self-lubricating device has an advantage that maintenance and handling are easy.

JP 58-178093 A Japanese Patent Laid-Open No. 3-186612

  However, the oil ring that rotates together with the rotating shaft may come into contact with the structure disposed around the oil ring, and abrasion powder may be generated due to the contact between the oil ring and the structure. The generated wear powder adheres to the outer peripheral surface of the rotating shaft or enters the bearing. In particular, since the oil ring that supplies lubricating oil to the slide bearing is supported by the rotating shaft while passing through the inside of the slide bearing, the wear powder generated when the oil ring comes into contact with the slide bearing is It tends to penetrate between the bearing surface of the slide bearing and the outer peripheral surface of the rotary shaft. For this reason, the life of the rotating shaft and the bearing may be shortened.

  The present invention has been made in view of the above-described conventional problems, and provides a bearing device in which wear powder is unlikely to be generated even when an oil ring contacts a structure disposed around the oil ring. Objective. Moreover, an object of this invention is to provide rotary machines, such as a pump provided with such a bearing apparatus.

  One aspect of the present invention for solving the above-described problems includes a bearing that supports an axial load and / or a radial load of a rotating shaft, a lubricating oil storage tank disposed below the bearing, and the rotating shaft. And an oil ring that scoops up the lubricating oil stored in the lubricating oil storage tank as the rotating shaft rotates, and both sides of the oil ring are made of a lipophilic material. This is a bearing device.

  In a preferred aspect of the present invention, the outer peripheral surface of the oil ring is made of a lipophilic material.

  Another aspect of the present invention is a rotating machine including a rotating shaft and the bearing device that rotatably supports the rotating shaft.

  Furthermore, another aspect of the present invention is a pump comprising a rotating shaft, an impeller fixed to the rotating shaft, and the bearing device that rotatably supports the rotating shaft. .

  According to the present invention, since both side surfaces of the oil ring are made of an oleophilic material, the lubricating oil always adheres to both side surfaces of the rotating oil ring. As a result, since the frictional force generated when the both side surfaces of the oil ring come into contact with the structure disposed around the oil ring is reduced, it is possible to provide a bearing device that is less likely to generate wear powder. . Moreover, this invention can provide rotary machines, such as a pump provided with such a bearing apparatus.

FIG. 1 is a cross-sectional view showing an example of a horizontal shaft single-stage pump provided with a bearing device according to an embodiment of the present invention. FIG. 2 is a cross-sectional view showing an example of a horizontal shaft multi-stage pump provided with a bearing device according to an embodiment of the present invention. FIG. 3 is a cross-sectional view showing the structure of a bearing device according to an embodiment of the present invention. 4 is a cross-sectional view taken along line AA in FIG. 5 is a cross-sectional view taken along line BB in FIG. FIG. 6 is a perspective view showing an example of an oil ring. FIG. 7 is a cross-sectional view of the oil ring shown in FIG.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a cross-sectional view showing an example of a horizontal shaft single-stage pump provided with a bearing device according to an embodiment of the present invention. A horizontal axis single-stage pump 100 as a rotating machine shown in FIG. 1 has an impeller 2 and a rotating shaft 1 to which the impeller 2 is fixed. The rotating shaft 1 extends horizontally. One end of the rotary shaft 1 is connected to a drive machine such as an electric motor (not shown), and the rotary shaft 1 and the impeller 2 are rotated by this drive machine. Moreover, the rotating shaft 1 is rotatably supported by a bearing device 9 provided in the vicinity of both ends thereof.

  The impeller 2 is disposed in the pump casing 5. The pump casing 5 shown in FIG. 1 has a spiral chamber 5a therein, and the impeller 2 is disposed in the spiral chamber 5a. When the impeller 2 rotates with the rotation of 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 spiral chamber 5 a, and the liquid is discharged from the discharge port 4. It is.

  The impeller 2 in the illustrated example has a double suction structure for sucking liquid from both sides thereof. The caps 2A and 2B are attached to the liquid inlet of the impeller 2, respectively. By designing the diameters of the caps 2A and 2B to be different from each other, a thrust force due to a pressure difference can be applied in one direction of the rotating shaft 1 and the rotating shaft 1 can be rotated in a stable state. This thrust force is supported by the thrust bearing 9 </ b> A of the bearing device 9. The thrust bearing 9 </ b> A is a double row rolling bearing that can receive a thrust force acting in both directions of the rotary shaft 1. In order to supply lubricating oil to the thrust bearing 9A, an oil ring 20 is disposed on the axial end portion side of the rotary shaft 1 of the thrust bearing 9A.

  In addition to the thrust bearing 9 </ b> A, two radial bearings 9 </ b> B are disposed in the vicinity of both end portions of the rotary shaft 1. The rotary shaft 1 is supported by a total of three bearings including these two radial bearings 9B and one thrust bearing 9A. In the present embodiment, a sleeve-type slide bearing is used as the radial bearing 9B. In the sleeve-type radial bearing 9B, two oil rings 20 for supplying lubricating oil are disposed between the bearing surface of the radial bearing 9B and the outer peripheral surface of the rotary shaft 1.

  FIG. 2 is a cross-sectional view showing an example of a horizontal shaft multi-stage pump provided with a bearing device according to an embodiment of the present invention. A horizontal axis multistage pump 100 as a rotating machine shown in FIG. 2 includes a plurality of impellers 2 and a rotary shaft 1 to which the impellers 2 are fixed. The rotating shaft 1 extends horizontally. The plurality of impellers 2 are arranged in series on the rotary shaft 1, and a plurality of diffusers 6 are arranged so as to surround each of the impellers 2. One end of the rotary shaft 1 is connected to a drive machine such as an electric motor (not shown), and the rotary shaft 1 and the impeller 2 are rotated by this drive machine. Moreover, the rotating shaft 1 is rotatably supported by a bearing device 9 provided in the vicinity of both ends thereof.

  The impeller 2 is disposed in the pump casing 5. When the plurality of impellers 2 rotate with the rotation of the rotating shaft 1, liquid such as water is sucked from the suction port 3, and the pressure of the liquid is increased by the action of the impeller 2 and the diffuser 6, and the liquid is discharged from the discharge port 4. Is exhaled from. Since the plurality of impellers 2 are arranged in the same direction, the thrust force generated by the pressure difference between the adjacent impellers 2 is overlapped by the number of impellers 2, and a large thrust force is generated. This thrust force is offset by the balance device 7 provided in the horizontal multistage pump 100, but a certain amount of thrust force remains during transient operation. This residual thrust force is supported by the thrust bearing 9 </ b> A of the bearing device 9. The thrust bearing 9 </ b> A is a double row rolling bearing that can receive a thrust force acting in both directions of the rotary shaft 1. In order to supply lubricating oil to the thrust bearing 9A, an oil ring 20 is disposed on the axial end portion side of the rotary shaft 1 of the thrust bearing 9A.

  In addition to the thrust bearing 9 </ b> A, two radial bearings 9 </ b> B that support the radial load of the rotating shaft 1 are disposed in the vicinity of both end portions of the rotating shaft 1. The rotary shaft 1 is supported by a total of three bearings including these two radial bearings 9B and one thrust bearing 9A. In the present embodiment, a sleeve-type slide bearing is used as the radial bearing 9B. In the sleeve-type radial bearing 9B, two oil rings 20 for supplying lubricating oil are disposed between the bearing surface of the radial bearing 9B and the outer peripheral surface of the rotary shaft 1. The configuration of the bearing device 9 disposed in the vicinity of both end portions of these rotary shafts 1 is the same as that of the horizontal shaft single-stage pump shown in FIG.

  In both cases of the horizontal shaft pump 100 shown in FIGS. 1 and 2, the rotary shaft 1 extends through the pump casing 5. A gap between the rotary shaft 1 and the pump casing 5 is sealed by a shaft seal device 8 such as a mechanical seal. Therefore, the liquid pressurized by the impeller 2 does not enter the bearing device 9.

  FIG. 3 is a cross-sectional view showing the structure of a bearing device according to an embodiment of the present invention. As shown in FIG. 3, the bearing device 9 includes a thrust bearing 9 </ b> A that supports the axial load and radial load of the rotating shaft 1 that extends horizontally, and a radial bearing 9 </ b> B that supports the radial load of the rotating shaft 1. Have. As the thrust bearing 9A of the present embodiment, a double row rolling bearing constituted by two angular ball bearings 31 and 32 is used, and a sleeve type sliding bearing is used as the radial bearing 9B.

  A lubricating oil storage tank 10 is disposed below the thrust bearing 9A and the radial bearing 9B, and the oil level of the lubricating oil stored in the lubricating oil storage tank 10 is indicated by a dotted line with a reference numeral 10A. . The amount of lubricating oil is controlled so that the oil level 10A in the lubricating oil storage tank 10 is constant. A cooling jacket 27 is provided below the lubricating oil storage tank 10, and the lubricating oil in the lubricating oil storage tank 10 is cooled by the coolant flowing through the cooling jacket 27. Instead of the cooling jacket 27, an air cooling structure with fins may be employed. Or it is good also as a structure which inserts a cooling fluid tube in the lubricating oil storage tank 10, and cools lubricating oil directly.

  As shown in FIG. 3, an oil ring 20 for supplying lubricating oil to the thrust bearing 9A is disposed on the axial end portion side of the rotary shaft 1 of the thrust bearing 9A. In the radial bearing 9B, two oil rings 20 for supplying lubricating oil are disposed between the bearing surface of the radial bearing 9B and the outer peripheral surface of the rotary shaft 1. The sleeve-type radial bearing 9 </ b> B has a cylindrical bearing body 43, and the inner peripheral surface of the bearing body 43 constitutes a bearing surface that supports the rotary shaft 1. A chamber 40 through which the oil ring passes is formed in the bearing body 43, and the oil ring 20 is supported by the rotary shaft 1 through the chamber 40.

  4 is a cross-sectional view taken along line AA in FIG. As shown in FIG. 4, the oil ring 20 disposed adjacent to the thrust bearing 9 </ b> A is passed through the gap 16 </ b> A formed in the fixing member 16 that fixes the outer rings of the angular ball bearings 31 and 32. Supported by the rotating shaft 1. Therefore, the fixing member 16 is a structure disposed around the oil ring 20. The oil ring 20 is supported by the rotary shaft 1 with its lower part immersed in the lubricating oil stored in the lubricating oil storage tank 10 (see FIG. 3). The oil ring 20 rotates in accordance with the rotation of the rotating shaft 1, thereby scooping up the lubricating oil stored in the lubricating oil storage tank 10. The lubricating oil pumped up by the oil ring 20 is supplied to the thrust bearing 9A through the rotary shaft 1.

  5 is a cross-sectional view taken along line BB in FIG. As shown in FIG. 5, the bearing body 43 of the radial bearing 9 </ b> B is provided with a chamber 40 through which the oil ring 20 passes. The oil ring 20 is supported by the rotating shaft 1 through the chamber 40. Is done. Therefore, the bearing main body 43 of the radial bearing 9 </ b> B is a structure disposed around the oil ring 20. The oil ring 20 rotates in accordance with the rotation of the rotating shaft 1, thereby scooping up the lubricating oil stored in the lubricating oil storage tank 10. The lubricating oil pumped up by the oil ring 20 is supplied between the bearing surface of the radial bearing 9 </ b> B and the outer peripheral surface of the rotary shaft 1.

  FIG. 6 is a perspective view showing an example of the oil ring 20. FIG. 7 is a cross-sectional view of the oil ring 20 shown in FIG. As shown in FIG. 3, the oil ring 20 shown in FIGS. 6 and 7 is disposed through the axial end portion side of the rotary shaft 1 of the thrust bearing 9A and the bearing main body 43 of the sleeve-type radial bearing 9B. Is done. As shown in FIGS. 6 and 7, two grooves 28 are formed on the inner peripheral surface of the oil ring 20. The groove 28 extends along the circumferential direction of the oil ring 20 over the entire circumference of the inner circumferential surface of the oil ring 20. The number of grooves 28 may be one, or may be three or more.

  When the oil ring 20 rotates with the rotary shaft 1 and the oil ring 20 moves away from the liquid surface 10A of the lubricating oil storage tank 10, the lubricating oil can be stored in the groove 28 formed on the inner peripheral surface of the oil ring 20. it can. The lubricating oil accumulated in the groove 28 is carried to the upper part of the rotating shaft 1 by the rotating oil ring 20. When the lubricating oil stored in the groove 28 comes into contact with the upper portion of the rotating shaft 1, the lubricating oil flows out from the groove 28 onto the rotating shaft 1 and then supplied to the bearings 9 </ b> A and 9 </ b> B.

  Although not shown, a plurality of recesses arranged along the circumferential direction of the oil ring 20 may be provided on the inner peripheral surface of the oil ring 20 instead of the groove 28. The rotating oil ring 20 can carry the lubricating oil stored in the recess to the upper part of the rotating shaft 1. When the lubricating oil accumulated in the concave portion comes into contact with the upper portion of the rotating shaft 1, the lubricating oil flows out from the concave portion onto the rotating shaft 1, and is then supplied to the bearings 9A and 9B.

  As shown in FIG. 7, both side surfaces 20A and 20B of the oil ring 20 are made of a lipophilic material. More specifically, one side surface 20A of the oil ring 20 is composed of a film 36 made of a lipophilic material, and the other side surface 20B is composed of a film 37 made of a lipophilic material. The lipophilic material is a general term for materials having an affinity for lubricating oil, and is, for example, a polymer material in which an oil component such as silicone oil or wax is dispersed. By applying a lipophilic material to the oil ring 20, the films 36 and 37 can be formed. The films 36 and 37 may be formed by attaching a sheet made of a lipophilic material to the oil ring 20.

  As shown in FIG. 3, both side surfaces 20A and 20B of the oil ring 20 are close to the side wall surface of the chamber 40 formed in the bearing body 43 of the radial bearing 9B. Therefore, both side surfaces 20A and 20B of the rotating oil ring 20 are likely to come into contact with the bearing body 43 of the radial bearing 9B.

  According to the present embodiment, since both side surfaces 20A, 20B of the oil ring 20 are constituted by the films 36, 37 made of a lipophilic material, the lubricating oil is always applied to the both side surfaces 20A, 20B of the rotating oil ring 20. It is attached. As a result, the frictional force generated when the both side surfaces 20A, 20B of the oil ring 20 and the bearing body 43 of the radial bearing 9B come into contact with each other can be reduced. be able to.

  The oil ring 20 having the structure shown in FIG. 7 is also used for the thrust bearing 9A. Therefore, even if both side surfaces 20A and 20B of the oil ring 20 that supplies the lubricating oil to the thrust bearing 9A come into contact with the fixing member 16, the generation of wear powder can be reduced.

  As shown in FIG. 7, the outer peripheral surface 20C of the oil ring 20 may be made of a lipophilic material. More specifically, the outer peripheral surface 20C of the oil ring 20 may be composed of a film 38 made of a lipophilic material. The outer peripheral surface 20C of the oil ring 20 shown in FIG. 7 is the outermost surface of the oil ring 20 composed of the left inclined portion P, the right inclined portion Q, and the flat portion R connecting the left inclined portion P and the right inclined portion Q. It is an outer peripheral surface. The shape of the outer peripheral surface 20C of the oil ring 20 is not limited to the embodiment shown in FIG. 7, and the cross section of the outer peripheral surface 20C may be a curved shape. The film 38 can be formed by applying a lipophilic material to the oil ring 20. The film 38 may be formed by attaching a sheet made of a lipophilic material to the oil ring 20. The film 38 constituting the outer peripheral surface 20C shown in FIG. 7 and the films 36 and 37 constituting the both side faces 20A and 20B may be integrally formed.

  Thus, since the outer peripheral surface 20C of the oil ring 20 is formed of the lipophilic material film 38, the lubricating oil is always attached to the outer peripheral surface 20C of the oil ring 20. As a result, the frictional force generated when the outer peripheral surface 20C of the oil ring 20 comes into contact with a structure (for example, the bearing body 43 or the fixing member 16 of the radial bearing 9B) arranged around the oil ring 20 is reduced. Therefore, the generation of wear powder can be further reduced.

  So far, the bearing device 9 according to the embodiment of the present invention has been described using the bearing device of the horizontal shaft pump as an example. However, this bearing device 9 can also be applied to rotating machines other than the horizontal shaft pump. For example, the bearing device 9 of the present invention can be applied to a rotary machine such as a compressor or a blower.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the technical idea described in the claims.

DESCRIPTION OF SYMBOLS 1 Rotating shaft 2 Impeller 3 Suction port 4 Discharge port 5 Pump casing 6 Diffuser 7 Balance device 8 Shaft seal device (mechanical seal)
DESCRIPTION OF SYMBOLS 9 Bearing apparatus 9A Thrust bearing 9B Radial bearing 10 Lubricating oil storage tank 10A Lubricating oil surface 16 Fixing member 20 Oil ring 27 Cooling jacket 31, 32 Angular ball bearing 36, 37, 38 Film 40 Room 43 Bearing main body 100 Horizontal shaft pump

Claims (4)

A bearing that supports the axial load and / or radial load of the rotating shaft;
A lubricating oil reservoir disposed below the bearing;
An oil ring supported by the rotating shaft and scooping up the lubricating oil stored in the lubricating oil storage tank as the rotating shaft rotates.
A bearing device characterized in that both sides of the oil ring are made of a lipophilic material.   The bearing device according to claim 1, wherein an outer peripheral surface of the oil ring is made of a lipophilic material. A rotation axis;
A rotating machine comprising: the bearing device according to claim 1 or 2 that rotatably supports the rotating shaft. A rotation axis;
An impeller fixed to the rotating shaft;
A pump comprising: the bearing device according to claim 1, which rotatably supports the rotating shaft.

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