JP6073746B2 - Lubricating oil outflow suppression device, rotating machine, lubricating oil outflow suppressing method - Google Patents

Description

  The present invention relates to a technique for suppressing the outflow of lubricating oil used in a bearing to the outside.

  In an oil lubricated bearing used for a rotary machine, for example, a pump, the lubricant is scattered by the ball bearing, and the lubricant adheres to the outer periphery of the main shaft or the inner surface of the bearing cover. When the through-hole through which the main shaft passes is formed in the bearing cover, the adhering lubricating oil flows out from the gap between the through-hole of the bearing cover and the main shaft.

  In order to suppress the outflow of such lubricating oil, conventionally, a lip seal has been provided between the penetrating portion of the bearing cover and the main shaft. In the method using the lip seal, the main shaft slides while the lip seal and the main shaft are in contact with each other during the rotation of the main shaft. Therefore, fine foreign matter (for example, iron generated by rust or wear) is formed between the lip seal and the main shaft. When the powder enters, the sliding part of the spindle wears out. When the degree of wear increases, the sealing performance deteriorates and the lubricating oil flows out to the outside. As a result, the spindle needs to be replaced.

JP-A-9-196186

  Instead of the lip seal, a labyrinth seal (for example, Patent Document 1 described above) can be used to suppress the outflow of the lubricating oil. For example, a groove called a labyrinth is provided in a through portion of the bearing cover, that is, a surface of the bearing cover that faces the outer surface of the main shaft. According to such a groove structure, the lubricating oil that has entered the gap between the main shaft and the bearing cover stays in the groove due to the surface tension of the lubricating oil and is guided downward along the groove. This groove is formed over almost the entire circumference of the penetrating part, and the bearing side surface of the bearing cover is replaced with the groove at the same depth as the groove, or more than the predetermined width at the bottom. If the notch part cut out at a deep depth is formed, the lubricating oil guided downward along the groove can be guided from the notch part to the oil reservoir. According to such a labyrinth seal, since the oil seal is performed in a state where the bearing cover and the main shaft are not in contact with each other, there is no problem like the lip seal described above.

  However, in the labyrinth seal described above, no groove is formed in the lowermost notch, and therefore the lubricating oil scattered in the notch tends to flow out to the atmosphere side. In addition, the depth of the grooves and the number of grooves are limited due to space restrictions and the like, and if the amount of scattered lubricant is large, there is a possibility that the outflow of the lubricant to the outside cannot be sufficiently suppressed only by the grooves. There is. Such a problem is not limited to the pump but is common to various rotating machines that employ oil-lubricated bearings. For this reason, there is a need for a technique that can suitably suppress the outflow of the lubricating oil from the oil-lubricated bearing to the outside.

  SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as, for example, the following forms.

According to a first aspect of the present invention, there is provided a lubricating oil outflow suppression device for a rotary machine, comprising: a main shaft extending in the axial direction; and a bearing that rotatably supports the main shaft and uses lubricating oil. Provided. This lubricating oil outflow suppression device is a bearing cover for covering one side of the bearing, and between the bearing and the bearing cover, a bearing cover in which a through hole for the main shaft to penetrate in the axial direction is formed, And an oil cover disposed so as to be separated from the main shaft and surround the periphery of the main shaft.

  According to this lubricating oil outflow suppression device, when the lubricating oil scatters from the bearing toward the bearing cover, the lubricating oil scatters by the oil cover. Therefore, it is possible to suppress the lubricating oil from entering the through hole of the bearing cover and flowing out to the outside.

  As a second aspect of the present invention, in the first aspect, the oil cover is a bottom surface orthogonal to the axis, the bottom surface having a first through hole through which the main shaft passes in the center, and the radial direction of the bottom surface You may provide the outer side surface formed over the whole circumferential direction from the outer edge part to the vicinity of a bearing toward the bearing side. According to this form, most of the lubricating oil scattered toward the radially outer side of the oil cover is captured by the outer side surface and stays inside the oil cover. Therefore, it is possible to prevent the lubricating oil from scattering to the outside in the radial direction of the oil cover and entering the bearing cover side from the outside in the radial direction of the oil cover. As a result, the penetration of the lubricating oil into the through hole of the bearing cover can be further suppressed.

  As a third mode of the present invention, in the second mode, the oil cover includes an inner side surface formed extending from the radially inner end of the bottom surface toward the bearing side over the entire circumferential direction. It may be. According to such a configuration, the lubricating oil scattered inside the oil cover is guided downward along the inner surface of the inner side surface, so that the lubricating oil is a gap between the main shaft and the oil cover or an oil draining ring. Can be prevented from entering the gap between the oil cover and the oil cover. Therefore, it can suppress that lubricating oil moves to the bearing cover side of an oil cover. As a result, the penetration of the lubricating oil into the through hole of the bearing cover can be further suppressed.

  As a fourth aspect of the present invention, in any of the first to third aspects, the oil cover may be fitted into a step portion formed inside the bearing cover. According to this form, the oil cover can be easily attached.

  According to a fifth aspect of the present invention, in any one of the first to fourth aspects, the lubricating oil outflow suppression device is an oil draining ring provided along the circumferential direction on the outer periphery of the main shaft, and includes a bearing and a bearing cover. An oil draining ring provided between the two may be provided. The oil cover may be disposed at a position that surrounds the periphery of the oil drain ring while being separated from the oil drain ring. In such a configuration, when the lubricating oil enters the bearing cover side on the oil drain ring from the gap between the oil cover and the oil drain ring, the lubricating oil is caused by centrifugal force accompanying rotation of the main shaft and the oil drain ring. It is blown away from the main shaft. According to such a configuration, the lubricating oil enters the bearing cover side from the gap between the oil cover and the main shaft from the main shaft through the gap between the oil cover and the main shaft, and the lubricating oil is separated from the main shaft by centrifugal force. Lubricating oil is blown away in a direction away from the main shaft from a position further away from the main shaft than in a configuration where the lubricating oil is blown away from the main shaft. Therefore, the penetration of the lubricating oil into the through hole of the bearing cover can be further suppressed.

  As a sixth aspect of the present invention, in the fifth aspect, the oil draining ring is formed to have a first portion and a diameter larger than that of the first portion, and closer to the bearing cover than the first portion. And a second portion that is positioned. The end of the oil cover on the axial line side may be disposed closer to the bearing cover than the end of the second part on the bearing side. According to this form, the lubricating oil scattered in the first part is less likely to enter the bearing cover side than the oil cover. Therefore, the penetration of the lubricating oil into the through hole of the bearing cover can be further suppressed.

As a seventh aspect of the present invention, in the fifth or sixth aspect, the portion of the inner surface of the bearing cover that faces the bearing is an oil relief that surrounds the outside of the through hole at least at a position above the center of the through hole. A groove may be formed. According to such a configuration, even when the lubricating oil has entered the bearing cover side of the oil cover, the lubricating oil scattered from the oil draining ring to the region outside the oil relief groove on the inner surface of the bearing cover is The oil is guided to the oil relief groove along the inner surface. Since the lubricating oil guided to the oil escape groove moves below the through hole along the oil escape groove due to gravity, the lubricating oil can be prevented from entering the through hole of the bearing cover.

  As an eighth embodiment of the present invention, in the seventh embodiment, the end surface on the outer circumferential side in the orthogonal direction orthogonal to the axis of the oil draining ring and the top on the inner peripheral side of the oil relief groove are the same in the radial direction. May be in position. According to this configuration, even if the lubricating oil enters the bearing cover side on the oil drain ring from the gap between the oil cover and the oil drain ring, almost all of the lubricating oil is outside the oil relief groove. Splash into the area. Therefore, the effect of the fifth embodiment can be maximized.

  As a ninth form of the present invention, in the fourth form or any of the fifth to eighth forms including at least the fourth form, the outer side surface has a lower end of the end portion on the bearing side, A notch penetrating in the thickness direction may be formed. According to such a configuration, the lubricating oil scattered on the bearing side of the bottom surface of the oil cover can be guided below the oil cover through the notch, so that the lubricating oil may stay on the bearing side of the oil cover. Absent.

  As a tenth aspect of the present invention, in the ninth aspect, the outer side surface may include a bent portion that extends from the base end of the notch portion to the side away from the axis. According to this aspect, the oil cover can be attached to the bearing cover by inserting the bent portion into the groove provided in the bearing cover for guiding the lubricating oil downward. That is, the oil cover can be easily positioned.

  As an eleventh aspect of the present invention, in the ninth or tenth aspect, a second through hole penetrating in the thickness direction of the bottom surface may be formed in the lower end portion of the bottom surface. The lowermost end of the second through hole may be arranged so as to be positioned below the liquid level of the lubricating oil. According to this configuration, the lubricating oil that has entered the bearing cover side of the oil cover and stayed below is more likely to move to the bearing side than the oil cover, and the level of the lubricating oil on the bearing cover side of the oil cover It is possible to prevent the level from becoming higher than the liquid level of the lubricating oil on the bearing side than the oil cover. As a result, it is possible to prevent the oil outer ring and the lubricating oil from coming into contact with each other due to the undulation of the lubricating oil level caused by the rotation of the bearing, thereby promoting the oil scattering. Accordingly, it is possible to suppress the oil that has entered the bearing cover side from the oil cover from staying on the side and the lubricating oil from entering the through hole of the bearing cover.

  As a twelfth aspect of the present invention, in any of the ninth to eleventh aspects, the oil cover may have a vertically symmetrical shape. According to such a form, the oil cover is not attached in a state where the upper and lower positions thereof are wrong. In other words, it is not necessary for the worker to distinguish and recognize the upper and lower positions of the oil cover, so that the oil cover is easily attached.

  As a thirteenth aspect of the present invention, in any one of the ninth to twelfth aspects, the bearing-side surface of the oil cover has at least a first through hole at a position above the center of the first through hole. An oil relief groove that surrounds the outside may be formed. According to such a form, the lubricating oil scattered on the oil cover can be guided to the oil relief groove and moved below the through hole of the bearing cover along the oil relief groove by gravity. Therefore, it is possible to suppress the lubricating oil from entering the through hole of the bearing cover.

  A fourteenth aspect of the present invention is provided as a rotating machine including a main shaft, a bearing, and the lubricating oil outflow suppression device according to any one of the first to thirteenth aspects. According to such a rotating machine, the same effects as those of the first to thirteenth embodiments are obtained.

  According to a fifteenth aspect of the present invention, in a rotary machine including a main shaft extending in the axial direction and a bearing that rotatably supports the main shaft and using the lubricating oil, the outflow of the lubricating oil is suppressed. Provided as a method. This method includes a bearing and a bearing cover for covering one side of the bearing, the bearing cover having a through hole through which the main shaft penetrates in the axial direction, and is separated from the main shaft. By installing an oil cover that is arranged so as to surround the periphery of the main shaft and blocking at least a part of the scattering of the lubricating oil from the bearing toward the bearing cover with the oil cover, the lubricating oil flows out from the through hole. To suppress. According to this method, the same effect as that of the first embodiment is obtained.

  The present invention is not limited to the above-described form, and can be realized as a bearing cover, an oil drain ring, or the like.

It is sectional drawing which shows schematic structure of the pump as 1st Example of this invention. It is sectional drawing which shows schematic structure of a lubricating oil outflow suppression apparatus. It is explanatory drawing which shows schematic structure of a bearing cover. It is explanatory drawing which shows schematic structure of an oil draining ring. It is explanatory drawing which shows schematic structure of an oil cover. It is sectional drawing which shows schematic structure of the lubricating oil outflow suppression apparatus as 2nd Example. It is explanatory drawing which shows the structure of the oil cover as a modification.

  A. First embodiment:

  FIG. 1 is a cross-sectional view showing a schematic configuration of a pump 20 as an embodiment of the present invention. As shown in the figure, a pump 20 as an example of a rotating machine includes a main shaft 30, a bearing casing 40, bearings 51 and 52, and a lubricant oil outflow suppression device 80. In the bearing casing 40, the main shaft 30 is formed extending along the axis AL direction orthogonal to the vertical (gravity) direction, and an impeller 35 is fixed around the main shaft 30 at one end thereof. On the other end side of the main shaft 30, the main shaft 30 is cantilevered by bearings 51 and 52. An electric motor (not shown) is connected ahead of the bearing 52 on the other end side of the main shaft 30. With such a configuration, the main shaft 30 and the impeller 35 rotate about the axis AL as the rotation center axis.

  The bearings 51 and 52 are ball bearings that use lubricating oil. An oil reservoir 41 is formed by the bearing casing 40 between the bearing 51 and the bearing 52. In the present embodiment, the oil level OL in the oil reservoir 41 is maintained in the vicinity of the center of the ball when the balls constituting the bearings 51 and 52 are positioned at the lowest position.

  The bearing casing 40 terminates at the position of the bearing 52 on the other end side of the main shaft 30, so that the outside of the bearing 52 (the side opposite to the bearing 51) is exposed from the bearing casing 40. One side of the bearing 52, that is, the exposed portion is covered with a bearing cover 60. In the present embodiment, the bearing cover 60 has a bottomed cylindrical cup shape. The end of the bearing cover 60 opposite to the bottom is formed in a flange shape, whereby the bearing cover 60 is attached to the bearing casing 40. A through hole 61 penetrating in the direction of the axis AL is formed at the bottom of the bearing cover 60. The main shaft 30 extends through the through hole 61 to the outside of the bearing cover 60.

An oil cover 90 and an oil drain ring 70 are disposed between the bearing 52 and the bearing cover 60. The bearing cover 60, the oil cover 90, and the oil drain ring 70 are used as a lubricating oil outflow suppression device 80 that suppresses the lubricating oil scattered from the bearing 52 from flowing out to the outside (on the side of the electric motor) when the main shaft 30 rotates. Function.

  FIG. 2 is a partially enlarged view of FIG. 1 showing a schematic configuration around the bearing 52 and the lubricating oil outflow suppression device 80. FIG. 3 shows a schematic configuration of the bearing cover 60. 3A is a cross-sectional view of the bearing cover 60 in the same cross section as FIG. 2, and FIG. 3B is an arrow view of the inner surface of the bearing cover 60 (the surface on the bearing 52 side). FIG. 4 shows a schematic configuration of the oil drain ring 70. 4A is a cross-sectional view of the oil drain ring 70 in the same cross section as FIG. 2, and FIG. 4B is an arrow view of the oil drain ring 70 viewed from the side where the bearing cover 60 is attached. is there. FIG. 5 shows a schematic configuration of the oil cover 90.

  As shown in FIGS. 2 and 3, an oil relief groove 62 is formed in a portion of the inner surface of the bearing cover 60 that faces the bearing 52. In the present embodiment, the part is formed as a plane orthogonal to the axis AL. The oil escape groove 62 surrounds the outside of the through hole 61 and is formed in an annular shape. The oil escape groove 62 has a top part 62a that is an end point on the outer peripheral side of the groove, a top part 62b that is an end point on the inner peripheral side of the groove, and a bottom part 62c that is the deepest part of the groove. .

  The outer peripheral end of the surface of the oil relief groove 62 (surface forming the groove), that is, the periphery of the top 62a, is an inclined surface that faces the bearing 52 side and obliquely intersects the axis AL at an angle θ. have. In the present embodiment, the surface between the top portion 62a and the bottom portion 62c of the oil escape groove 62 is not limited to the end portion on the outer peripheral side, but extends from the top portion 62a to the bottom portion 62c at an angle θ with respect to the axis line AL. In other words, it is formed so as to approach the axis AL as it goes from the top 62a to the bottom 62c. In this embodiment, the angle θ is a constant value from the top 62a to the bottom 62c. According to the shape of the oil relief groove 62, the outer side of the inner surface of the bearing cover 60 is outside the groove 62 at a position above (in the vertical direction) the center of the through hole 61 (position through which the axis AL passes). It is easy to guide the lubricating oil scattered on the side surface 63 to the oil escape groove 62, more specifically to the bottom 62c. Further, at a position below the center of the through hole 61, the lubricating oil in the oil release groove 62 can be easily guided to the outside of the oil release groove 62, that is, below the through hole 61.

  In order to guide the lubricating oil over a wide range while ensuring the inclination angle of the surface of the oil relief groove 62 that can guide the lubricating oil suitably, the angle θ should be 30 ° or more and 75 ° or less. desirable. In the present embodiment, the angle θ is 45 °. The angle θ may change depending on the position.

  An end portion on the inner peripheral side of the surface of the oil escape groove 62, that is, the periphery of the top portion 62b is formed in parallel to the axis AL. In the present embodiment, the surface between the top portion 62b and the bottom portion 62c of the oil escape groove 62 is not limited to the end portion on the inner peripheral side, and is formed in parallel to the axis AL from the top portion 62b to the bottom portion 62c. Yes. According to the shape of the oil relief groove 62, the lubricating oil guided to the oil relief groove 62 is less likely to enter the inner side surface 64 inside the oil relief groove 62. However, the inner peripheral end of the surface of the oil relief groove 62 may be formed as an inclined surface that obliquely intersects the axis AL and faces the opposite side of the bearing 52. That is, the inner peripheral end of the surface of the oil escape groove 62 may be formed so as to approach the axis AL as it goes from the top 62b to the bottom 62c. Furthermore, the surface between the top part 62b and the bottom part 62c may be formed as an inclined surface facing the side opposite to the bearing 52 that obliquely intersects the axis AL from the top part 62b to the bottom part 62c. . These configurations also have the same effect as the configuration parallel to the axis AL described above.

According to the oil release groove 62 described above, when the lubricating oil scattered on the outer side surface 63 outside the oil release groove 62 moves downward along the outer side surface 63 by gravity, the lubricating oil can be captured. The lubricating oil trapped in the oil release groove 62 moves below the through hole 61 along the annular oil release groove 62 by gravity and returns to the oil reservoir 41. Therefore, it is possible to suppress the lubricating oil scattered on the outer surface 63 from entering the through hole 61 of the bearing cover 60 and flowing out to the outside through the gap between the main shaft 30 and the surface forming the through hole 61 of the bearing cover 60. .

  As shown in FIGS. 2 and 3, at least one (here, two) grooves 65 are formed along the circumferential direction on the surface of the bearing cover 60 where the through hole 61 is formed. The groove 65 constitutes a labyrinth seal. In addition, a notch 66 is formed below the surface of the bearing cover 60 where the through hole 61 is formed. The groove 65 is formed in an annular shape except for the region where the notch 66 is formed, and communicates with the notch 66 at the lower end thereof. According to this configuration, even if a small amount of lubricating oil enters the through hole 61 even by the lubricating oil outflow suppression device 80, the lubricating oil is captured by the notch 66 and is stored through the notch 66. Return to 41.

  As shown in FIG. 2, the oil drain ring 70 is provided along the circumferential direction on the outer periphery of the main shaft 30 between the bearing 52 and the bearing cover 60. A through hole 74 having a diameter substantially the same as the diameter of the main shaft 30 is formed at the center of the oil drain ring 70 (see FIG. 4). In this embodiment, the oil drain ring 70 is fixed to the main shaft 30 by passing the main shaft 30 through the through hole 74 and then screwing. For this reason, when the main shaft 30 rotates, the oil drain ring 70 rotates together with the main shaft 30.

  As shown in FIGS. 2 and 4, the oil drain ring 70 includes a first portion 71 extending along the axis AL direction, and a second portion 72 positioned closer to the bearing cover 60 than the first portion 71. Is provided. The second portion 72 is formed with a larger diameter than the first portion 71. As shown in FIG. 2, the oil draining ring 70 is formed so as to extend almost over the entire area between the bearing cover 60 and the bearing 52, leaving a slight gap with the inner surface 64 of the bearing cover 60. . The end of the first portion 71 on the bearing 52 side in the axis AL direction is in contact with the outer ring of the bearing 52. According to this configuration, the lubricating oil scattered from the bearing 52 toward the main shaft 30 is blocked by the first portion 71 and is blown outward in the radial direction by the centrifugal force of the rotating first portion 71. For this reason, the lubricating oil adheres to the main shaft 30, and the lubricating oil moves along the main shaft 30 in the direction toward the bearing cover 60 and does not flow out to the outside.

  As shown in FIG. 2, the height in the radial direction of the oil drain ring 70 is a range in which the end surface 72 a on the outer side in the circumferential direction of the second portion 72 is not in contact with the oil level OL. In this way, when the oil drain ring 70 rotates together with the main shaft 30, the second portion 72 does not come into contact with the oil level OL and the lubricating oil does not scatter.

  According to the oil draining ring 70 described above, the lubricating oil splashed toward the region corresponding to the outer diameter of the oil draining ring 70 (second portion 72), that is, the inner surface 64 is blocked by the oil draining ring 70. Therefore, the scattered lubricating oil can be prevented from landing on the inner surface 64. Accordingly, the lubricating oil lands on the inner side surface 64, the lubricating oil enters the through hole 61 of the bearing cover 60, and flows out to the outside through a gap between the main shaft 30 and the surface forming the through hole 61 of the bearing cover 60. Can be suppressed.

Furthermore, in the present embodiment, as shown in FIG. 2, the end surface 72a on the outer side in the circumferential direction of the oil draining ring 70 and the top portion 62b on the inner peripheral side of the oil relief groove 62 are at the same position in the radial direction. In other words, in the surface direction orthogonal to the axis AL, the entire area of the inner surface 64 inside the groove 62 is blocked by the oil drain ring 70 from scattering of the lubricating oil. This is combined with the fact that the lubricating oil scattered on the outer side surface 63 outside the oil escape groove 62 is prevented from entering the through hole 61 by the groove 62, and the effect of suppressing the outflow of the lubricating oil to the outside is remarkably increased. Make it big.
Further, since the lubricating oil is less likely to enter the gap between the bearing cover 60 and the oil drain ring 70 as compared with the case where the top portion 62b is closer to the axis AL than the end surface 72a, the intrusion of the lubricating oil into the through hole 61 is suppressed. The However, the configuration in which the top portion 62b is closer to the axis AL than the end surface 72a is not excluded. Similarly, the configuration in which the end surface 72a is closer to the axis AL than the top 62b is not excluded.

  As shown in FIGS. 2 and 4, the surface of the second portion 72 of the oil drain ring 70 on the bearing cover 60 side (the surface facing the inner surface 64) is outside the oil drain ring 70 from the axis AL side. A groove 73 extending toward the radial side is formed. In the present embodiment, the groove 73 extends in the radial direction. A plurality of the grooves 73 are formed along the circumferential direction. FIG. 4B shows an example in which six grooves 73 are formed at equiangular intervals in the circumferential direction. Since the groove 73 is formed, the shape of the groove 73 performs the same function as the impeller of the pump when the oil draining ring 70 rotates together with the main shaft 30. Even if the lubricating oil enters between them, the lubricating oil is easily discharged in a direction away from the main shaft 30 (through hole 61) by centrifugal force. As a result, the lubricating oil can be further suppressed from flowing out from the through hole 61.

  Moreover, as shown in FIG. 4, the groove 73 formed in the oil drain ring 70 is open on the outer peripheral side and closed on the inner peripheral side. That is, the groove end 73 a that is the outer peripheral end of the groove 73 extends to the outer surface of the surface of the oil drain ring 70 on the bearing cover 60 side, and the groove end 73 b that is the inner peripheral end of the groove 73. Is terminated before reaching the through hole 74. According to this configuration, it is possible to further suppress the lubricating oil from entering the through hole 74 side, that is, the main shaft 30 side. In the present embodiment, the groove end 73b has a semicircular shape.

  As shown in FIG. 2, the oil cover 90 is disposed between the bearing 52 and the bearing cover 60 so as to be separated from the main shaft 30 and surround the main shaft 30. In this embodiment, since the oil drain ring 70 is attached around the main shaft 30, the oil cover 90 is disposed so as to be separated from the oil drain ring 70 and surround the periphery of the oil drain ring 70. Yes. It is desirable to make the gap D1 between the oil cover 90 and the oil drain ring 70 as small as possible within a range where they do not contact each other. In this embodiment, the oil cover 90 is fitted into a stepped portion 67 formed inside the bearing cover 60. The stepped portion 67 is formed on the outer side in the radial direction than the outer side surface 63. With this configuration, the oil cover 90 can be easily attached. However, any method can be adopted as a method of attaching the oil cover 90. For example, the oil cover 90 may be configured to be fitted and attached to the outer edge portion of the bearing 52. According to the oil cover 90, it is possible to block the lubricating oil scattered from the oil cover 90 toward the bearing cover 60 more radially outward than the oil drain ring 70.

  As shown in FIGS. 2 and 5, the oil cover 90 includes a bottom surface 91 and an outer side surface 92. The bottom surface 91 is a surface orthogonal to the axis AL and has a substantially circular outer shape. A first through hole 99 through which the main shaft 30 and the oil drain ring 70 penetrate is formed inside the bottom surface 91. The outer side surface 92 is formed to extend from the radially outer end of the bottom surface 91 to the vicinity of the bearing 52. The outer side surface 92 is formed over the entire circumferential direction. Most of the lubricating oil scattered toward the outside in the radial direction of the oil cover 90 is captured by the outer side surface 92 and stays inside the oil cover 90. For this reason, it is possible to reduce the risk that the lubricating oil scatters on the outer side in the radial direction of the oil cover 90 and enters the bearing cover 60 side from the outer side in the radial direction of the oil cover 90.

As shown in FIG. 5, a notch 97 penetrating in the thickness direction of the outer side surface 92 is formed at the lower end of the end portion of the outer side surface 92 on the bearing 52 side. The lubricating oil closer to the bearing 52 than the oil cover 90, for example, the lubricating oil scattered from the bearing 52 toward the oil cover 90 and guided downward through the oil cover 90, is guided downward via the notch 97. It is burned. Therefore, it is possible to prevent the lubricating oil from staying inside the oil cover 90 and locally increasing the oil level inside the oil cover 90. As a result, the risk of the lubricating oil entering the bearing cover 60 side from the oil cover 90 can be reduced.

  A bent portion 95 is formed at the base end of the cutout portion 97 of the outer side surface 92 so as to extend away from the axis AL. The oil cover 90 can be attached to the bearing cover 60 by inserting the bent portion 95 into the groove 68 (see FIG. 3) of the bearing cover 60. The groove 68 is provided to guide the lubricating oil guided downward by the oil escape groove 62 further downward. According to the bent portion 95, the oil cover 90 can be easily positioned.

  A second through hole 93 penetrating in the thickness direction of the bottom surface 91 is formed at the lower end portion of the bottom surface 91. The lowermost end 93 a of the second through hole 93 is provided at a position below the oil level OL in the oil reservoir 41. The second through hole 93 can suppress the lubricant oil that has entered the bearing cover 60 side from the oil cover 90 from staying downward. Specifically, since the lubricating oil staying below the space between the oil cover 90 and the bearing cover 60 can be conducted to the bearing 52 side of the oil cover 90 by the second through hole 93, the second through hole As compared with the case where there is no 93, the liquid level of the staying lubricating oil can be reduced. Therefore, the risk of the lubricating oil entering the through hole 61 can be reduced. It is desirable that the uppermost end 93b of the second through hole 93 is disposed at a position below the oil level OL of the lubricating oil.

  The oil cover 90 is formed in a vertically symmetrical shape. That is, the oil cover 90 is formed with a notch 98, a bent portion 96, and a second through hole 94 at positions that are vertically symmetrical with the notch 97, the bent portion 95, and the second through hole 93, respectively. Has been. According to such a configuration, when attaching the oil cover 90, the worker does not need to distinguish and recognize the upper and lower positions of the oil cover 90, so that the operation of attaching the oil cover 90 is facilitated.

  The second through hole 94 has a further effect. That is, since the opening area of the oil cover 90 (bottom surface 91) is increased by the second through hole 94, the heat in the internal space of the oil cover 90 is suitably dissipated, and the lubricating oil in the bearing 52 becomes excessively high in temperature. Can be suppressed. In the case where the surface of the bearing 52 on the bearing 51 side is covered to prevent the lubricant from scattering to the bearing 52 side, heat is easily trapped inside the bearing 52, and such a configuration is particularly effective. Such a through hole in the bottom surface 91 may be formed in an arbitrary number at an arbitrary position according to desired heat dissipation characteristics.

  In this embodiment, as shown in FIG. 2, the oil cover 90 is such that the end on the axis AL side of the oil cover 90 is bearing than the end on the bearing 52 side of the second portion 72 of the oil drain ring 70. It arrange | positions so that it may be located in the cover 60 side. In other words, the bottom surface 91 is located closer to the bearing cover 60 than the end of the second portion 72 of the oil drain ring 70 on the bearing 52 side in the direction of the axis AL. According to such a configuration, the lubricating oil scattered in the first portion 71 is less likely to enter the bearing cover 60 side than the oil cover 90. Specifically, the position of the gap between the bottom surface 91 and the oil draining ring 70 (second portion 72) is offset by a distance D2 from the bearing 52 side end of the second portion 72 toward the bearing cover 60 side. Therefore, even if the lubricating oil adhering to the first part 71 or the lubricating oil adhering to the end face on the bearing 52 side of the second part 72 is blown away in the direction away from the axis AL by centrifugal force, these lubrication Oil is less likely to enter the bearing cover 60 side than the oil cover 90.

According to the lubricating oil outflow suppression device 80 described above, the lubricating oil scattered from the bearing 52 toward the bearing cover 60 is blocked by the oil cover 90 and the oil drain ring 70. For this reason, most of the scattered lubricating oil is returned to the oil reservoir 41 without entering the bearing cover 60 side from the outer surface 63. Part of the scattered lubricating oil may enter the bearing cover 60 rather than the oil cover 90 through the gap between the oil cover 90 and the oil drain ring 70. However, in this case, the lubricating oil that has traveled on the second portion 72 and has entered the bearing cover 60 from the gap is blown away from the axis AL by the centrifugal force, that is, outside the oil relief groove 62. . As a result, the lubricating oil is captured in the oil escape groove 62 and returned to the oil reservoir 41. Further, even if a very small amount of lubricating oil enters the through hole 61 without being caught by the oil escape groove 62, the lubricating oil is caught by the groove 65 as a labyrinth seal and returned to the oil reservoir 41. . Therefore, the outflow of the lubricating oil to the outside can be suppressed with high reliability.

B. Second embodiment:
FIG. 6 shows a schematic configuration around the lubricating oil outflow suppression device 180 as the second embodiment. In FIG. 6, the same reference numerals as those in FIG. 2 are assigned to the same constituent elements as those of the lubricating oil outflow suppression apparatus 80 among the constituent elements of the lubricating oil outflow suppression apparatus 180. The lubricating oil outflow suppression device 180 differs from the lubricating oil outflow suppression device 80 only in the shapes of the oil drain ring 170 and the oil cover 190. The oil cover 190 includes an inner side surface 101 in addition to the components of the oil cover 90. The inner side surface 101 is formed extending from the radially inner end of the bottom surface 91 toward the bearing 52 side. The inner side surface 101 is formed over the entire circumferential direction.

  The second portion 172 of the oil draining ring 170 is formed to extend longer to the bearing 52 side than the second portion 72 of the first embodiment. Accordingly, the first part 171 is formed shorter than the first part 71 of the first embodiment. As a result, the inner side surface 101, that is, the end portion on the axis line AL side of the oil cover 190 is entirely located closer to the bearing cover 60 than the end portion on the bearing 52 side of the second portion 172.

  According to the lubricating oil outflow suppression device 180, the position of the gap between the inner side surface 101 and the oil drain ring 170 (second portion 172) is from the end of the second portion 172 on the bearing 52 side to the bearing cover 60 side. Therefore, the lubricant adhering to the first part 171 and the lubricant adhering to the end face on the bearing 52 side of the second part 172 fly away in the direction away from the axis AL by centrifugal force. Even if this is done, these lubricating oils are less likely to enter the bearing cover 60 side than the oil cover 190.

  In addition, according to the lubricating oil outflow suppression device 180, the lubricating oil scattered inside the oil cover 190 is guided downward along the inner surface of the inner side surface 101, so that the lubricating oil is separated from the second portion 172 and the oil. Intrusion into the gap between the cover 190 can be suppressed. Therefore, it can suppress that lubricating oil moves to the bearing cover 60 side of the oil cover 190. FIG. As a result, the penetration of the lubricating oil into the through hole 61 of the bearing cover 60 can be further suppressed.

C. Variations:
C-1. Modification 1:
FIG. 7 shows a configuration of an oil cover 290 as a modification of the oil cover 90 described above. In FIG. 7, the same components as those of the oil cover 90 among the components of the oil cover 290 are denoted by the same reference numerals as those in FIG. 5. The oil cover 290 is different from the oil cover 90 only in that oil relief grooves 297 and 298 are formed on the bottom surface 291. The oil escape grooves 297 and 298 are formed so as to surround the outside of the first through hole 99 at positions avoiding the second through holes 93 and 94, respectively. According to such a configuration, the lubricating oil scattered on the oil cover 90 can be guided to the oil escape grooves 297 and 298 and can be moved below the through hole 61 along the oil escape grooves 297 and 298 by gravity. Therefore, it is possible to further suppress the lubricating oil from entering the through hole 61. Such an oil relief groove may be annular or one groove communicating at the top. Further, such an oil relief groove may be formed at least at a position above the center of the first through hole 99 of the oil cover 290.

C-2. Modification 2:
Some of the various configurations described above can be omitted as appropriate. For example, the bent portions 95 and 96 of the oil covers 90 and 190 may be omitted. Alternatively, the second portion 72 of the oil drain ring 70
May be omitted. In this case, the 1st site | part 71 may be formed also in the position of the 2nd site | part 72 in the above-mentioned Example. Of course, the oil drain ring 70 itself may be omitted. In this case, the outer side surface 92 of the oil cover 90 is preferably formed to extend to the vicinity of the main shaft 30. Even with these configurations, the oil cover 90 can prevent the lubricant from flowing out. However, from the viewpoint that the lubricating oil can be blown away from the main shaft 30 by a centrifugal force in a direction away from the main shaft 30, that is, a direction away from the through hole 61, the oil cover 90 is It is more desirable to include the ring 70, and it is more desirable that the oil draining ring 70 includes the second portion 72.
C-3. Modification 3:
The oil release groove 62 is not necessarily formed in an annular shape. The oil escape groove 62 only needs to surround the outside of the through hole 61 at a position above the center of the through hole 61 in order to suppress the penetration of the lubricating oil into the through hole 61. For example, the oil escape groove 62 may have an inverted U shape or an arc shape that terminates below the center of the through hole 61. Even with such a shape, the lubricating oil is difficult to move in the direction opposite to the direction of gravity, that is, upward, so that the penetration of the lubricating oil into the through hole 61 can be suitably suppressed.

  Moreover, the cross-sectional shape of the oil escape groove 62 is not limited to the above-described example, and may be various shapes. For example, the outer peripheral end and the inner peripheral end of the oil relief groove 62 may be cut in parallel to the axis AL up to the bottom surface formed as a plane orthogonal to the axis AL. . Alternatively, a plane parallel to the axis AL or a plane orthogonal to the axis AL may be partially formed in the middle between the top 62a and the bottom 62c. Alternatively, there may be an uneven shape in the middle between the top 62b and the bottom 62c.

C-4. Modification 4:
The oil relief groove 62 and the oil draining ring 70 described above exhibit a remarkable lubricating oil outflow suppressing effect by combining both of them, but only one of them can be used alone. For example, the above oil relief groove 62 and labyrinth seal may be combined. Even if it does in this way, compared with the case where the outflow of lubricating oil is suppressed only by the labyrinth seal, the lubricating oil outflow suppressing effect can be enhanced. In this case, the oil relief groove 62 is desirably provided in the vicinity of the through hole 61.

C-5. Modification 5:
The shape of the groove 73 of the oil drain ring 70 can be an arbitrary shape. For example, the groove end 73b may terminate in a rectangular shape. Alternatively, the groove end 73b may be opened in the same manner as the groove end 73a. Of course, the groove 73 may not be formed.

C-6. Modification 6:
The above-described configuration for suppressing the outflow of the lubricating oil is not limited to the pump 20 and can be applied to various rotating machines including a bearing using the lubricating oil, such as a compressor and a blower.

  The embodiments of the present invention have been described above based on some examples. However, the above-described embodiments of the present invention are for facilitating the understanding of the present invention and limit the present invention. It is not a thing. The present invention can be changed and improved without departing from the gist thereof, and the present invention includes the equivalents thereof. Moreover, in the range which can solve at least one part of the subject mentioned above, or the range which exhibits at least one part of an effect, the combination of each component described in the claim and the specification, or omission is possible. .

DESCRIPTION OF SYMBOLS 20 ... Pump 30 ... Main shaft 35 ... Impeller 40 ... Bearing casing 41 ... Oil sump 51, 52 ... Bearing 60 ... Bearing cover 61 ... Through-hole 62 ... Oil relief groove 62a, 62b ... Top part 62c ... Bottom part 63 ... Outer surface 64 ... Inner side surface 65 ... groove 66 ... notched portion 67 ... stepped portion 68 ... groove 70 ... oil drain ring 71 ... first portion 72 ... second portion 72a ... end surface 73 ... groove 73a, 73b ... groove end 74 ... through hole 80 ... Lubricating oil outflow suppression device 90,290 ... oil cover 91,291 ... bottom face 92 ... outer side face 93,94 ... second through hole 95,96 ... bent part 97,98 ... notch part 99 ... first through hole 297 , 298 ... Oil relief groove AL ... Axis line OL ... Oil level

Claims (11)

A lubricating oil outflow suppression device for a rotary machine, comprising: a main shaft extending in the axial direction; and a bearing that rotatably supports the main shaft, the bearing using lubricating oil,
A bearing cover for covering one side of the bearing, the bearing cover having a through hole for the main shaft to penetrate in the axial direction;
An oil cover disposed between the bearing and the bearing cover so as to be separated from the main shaft and surround the main shaft ;
An oil draining ring provided along the circumferential direction on the outer periphery of the main shaft, the oil draining ring provided between the bearing and the bearing cover;
With
The oil cover is disposed at a position surrounding the oil drain ring while being separated from the oil drain ring,
The oil drain ring is
A first site;
A second portion having a diameter larger than that of the first portion and positioned closer to the bearing cover than the first portion;
With
The end portion on the axis line side of the oil cover is disposed closer to the bearing cover than the end portion on the bearing side of the second portion.
Lubricant spill suppression device.   A lubricating oil outflow suppression device for a rotary machine, comprising: a main shaft extending in the axial direction; and a bearing that rotatably supports the main shaft, the bearing using lubricating oil,
  A bearing cover for covering one side of the bearing, the bearing cover having a through hole for the main shaft to penetrate in the axial direction;
  An oil cover disposed between the bearing and the bearing cover so as to be separated from the main shaft and surround the main shaft;
  An oil draining ring provided in a circumferential direction on an outer periphery of the main shaft, the bearing and the bearing
Oil drain ring provided between the cover and
  With
  The oil cover is disposed at a position surrounding the oil drain ring while being separated from the oil drain ring,
  An oil relief groove that surrounds the outside of the through hole is formed at a position at least above the center of the through hole in a portion facing the bearing on the inner surface of the bearing cover,
  The end face on the outer side in the circumferential direction of the oil draining ring and the top portion on the inner circumferential side of the oil relief groove are at the same position in the radial direction.
  Lubricant spill suppression device. The lubricating oil spill suppression device according to claim 2 ,
The oil cover is
A bottom surface orthogonal to the axis, wherein the bottom surface is formed with a first through hole through which the main shaft passes;
A lubricant oil outflow suppression device comprising: an outer side surface formed over the entire circumferential direction from the radially outer end of the bottom surface toward the bearing side and in the vicinity of the bearing. The lubricating oil outflow suppression device according to claim 3 ,
The oil cover according to claim 1, wherein the oil cover includes an inner side surface formed to extend from the radially inner end of the bottom surface toward the bearing side over the entire circumferential direction. The lubricating oil spillage suppression device according to any one of claims 2 to 4 ,
The oil cover is a lubricating oil outflow suppressing device fitted in a step formed inside the bearing cover.   A lubricating oil outflow suppression device for a rotary machine, comprising: a main shaft extending in the axial direction; and a bearing that rotatably supports the main shaft, the bearing using lubricating oil,
  A bearing cover for covering one side of the bearing, the bearing cover having a through hole for the main shaft to penetrate in the axial direction;
  An oil cover disposed between the bearing and the bearing cover so as to be separated from the main shaft and surround the main shaft;
  With
  The oil cover is
    A bottom surface orthogonal to the axis, wherein the bottom surface is formed with a first through hole through which the main shaft passes;
    An outer side surface formed over the entire circumferential direction from the radially outer end of the bottom surface to the vicinity of the bearing toward the bearing side;
  With
  The oil cover is fitted into a step formed inside the bearing cover,
  On the outer side surface, a notch that penetrates in the thickness direction of the side surface is formed at the lower end of the bearing-side end portion.
  Lubricant spill suppression device. The lubricating oil outflow suppression device according to claim 6 ,
The lubricating oil outflow suppression device, wherein the outer side surface includes a bent portion formed to extend from a base end of the notch portion to a side away from the axis. The lubricating oil outflow suppression device according to claim 6 or 7 ,
A second through-hole penetrating in the thickness direction of the bottom surface is formed at the lower end of the bottom surface,
The lubricating oil outflow suppression device is arranged so that a lowermost end of the second through hole is positioned below a liquid surface of the lubricating oil. A lubricating oil spillage suppression device according to any one of claims 6 to 8 ,
The oil cover has a vertically symmetrical shape. A lubricating oil spillage suppression device according to any one of claims 6 to 9 ,
An oil spillage suppressing device in which an oil relief groove surrounding the outside of the first through hole is formed on the bearing side surface of the oil cover at least at a position above the center of the first through hole. The rotary machine provided with the said main shaft, the said bearing, and the lubricating oil outflow suppression apparatus as described in any one of Claims 1 thru | or 10 .

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