CN205446419U - Lubricating oil spills and prevents structure and pump - Google Patents

Abstract

A lubricating oil leakage prevention structure and a pump that can ensure sealing performance by using centrifugal force, can further ensure sealing performance by making the gap between sealing parts narrower, and can further reduce the length of the rotating shaft. The lubricating oil leakage prevention structure has The rotating shaft rotatably supported by the housing by the bearing and the non-contact sealing part which prevents the leakage of lubricating oil have a stationary part fixed to the housing and a movable part fixed to the rotating shaft. The movable part, wherein the movable part of the non-contact seal part has: a diameter-expanding surface extending so as to gradually expand in a radial direction of the rotating shaft toward the bearing side; and a protruding portion that protrudes outward in the radial direction of the rotating shaft on the bearing side of the expanded diameter surface, and whose outer diameter in the radial direction of the rotating shaft is larger than that of the expanded diameter surface. The maximum outer diameter of the radial surface in the radial direction of the axis of rotation.

Description

Lubricating oil leakage prevention structure and pump

technical field

The utility model relates to a lubricating oil leakage prevention structure and a pump with the lubricating oil leakage prevention structure.

Background technique

In the structure where the rotating shaft rotates at a high speed, such as a pump, and the rotating shaft is supported by bearings, it is usually necessary to use lubricating oil to lubricate the bearings, and in this type of oil-impregnated lubricated bearing structure, it is usually necessary to install anti-lubrication Oil leaks out of the structure.

In general, there are two types of lubricating oil leakage preventing structures: a contact seal structure and a non-contact seal structure. In the non-contact seal structure, the seal is performed by lubricating oil, and in the contact seal structure, the seal is performed by abutting the seal member against the rotating shaft or the like. Therefore, compared with the contact-type seal structure, the non-contact-type seal structure is not easy to wear on the rotating shaft, has better sealing performance, and can be used for a long time and is widely used.

Conventionally, there is a non-contact seal structure in which a labyrinth seal member is provided on a rotating shaft. In such a structure, in order to obtain sufficient sealing performance, it is necessary to make the labyrinth seal member long in the axial direction, resulting in an elongated rotating shaft and a large overall size.

In this regard, Patent Document 1 discloses a lubricating oil leakage prevention structure. Referring to Fig. 1 of Patent Document 1, in the housing 4, a shaft sleeve 3 is provided on the rotating shaft, and the shaft sleeve 3 is provided with an inclined sealing surface 6 and an oil baffle plate 8 that expand in diameter toward the bearing 2 side. One side of the sealing surface 6 is provided with a spiral seal 7 . Utilizing the centrifugal force generated when the rotating shaft rotates, the inclined sealing surface 6, the oil baffle plate 8 and the screw seal 7 prevent lubricant oil from leaking out from the bearing 2 side, and the axial dimension can be reduced.

prior art literature

patent documents

Patent Document 1: Japanese Patent Application Laid-Open No. 8-168202

However, in the lubricating oil leakage prevention structure of Patent Document 1 mentioned above, since the height of the inclined sealing surface and the oil baffle plate are the same, oil is easily transferred to the inclined sealing surface. And the inclination angle of the inclined sealing surface is more than 45°. When the gap size in the direction perpendicular to the inclined sealing surface is constant, the larger the inclination angle, the larger the clearance of the inclined sealing surface in the radial direction of the rotating shaft, reducing the improved sealing performance. Also, further reduction in the axial length is required.

Utility model content

This utility model was proposed in view of the above problems, and its main purpose is to provide a lubricating oil leakage prevention structure and a pump having the lubricating oil leakage prevention structure, which can ensure the sealing performance by utilizing centrifugal force, and can make the gap between the sealing part The sealing performance can be further ensured by narrowing, and the length of the rotating shaft can be further reduced.

In one embodiment of the present invention, a lubricating oil leakage prevention structure is provided, the lubricating oil leakage prevention structure has a rotating shaft rotatably supported by a housing via a bearing and a non-contact seal portion for preventing lubricating oil leakage, The non-contact sealing part has a stationary part fixed to the housing and a movable part fixed to the rotating shaft, wherein the movable part of the non-contact sealing part has an enlarged diameter surface, and the enlarged diameter a surface extending in such a manner that it gradually increases in diameter along the radial direction of the rotating shaft as it goes toward the bearing side; The bearing side protrudes outward in the radial direction of the rotating shaft, and the outer diameter of the protrusion in the radial direction of the rotating shaft is larger than the maximum diameter of the expanding surface in the radial direction of the rotating shaft. outside diameter.

According to the structure of the present invention, the outer diameter of the protrusion is greater than the maximum outer diameter of the enlarged diameter surface, specifically, when the protrusion is viewed from the side of the protrusion opposite to the enlarged diameter surface in the axial direction, The region surrounded by the circumferentially continuous outermost boundary of the protruding portion covers the diameter-expanding surface, so the sealing performance can be ensured by centrifugal force, and the sealing performance can be further ensured by making the gap of the sealing portion in the radial direction of the rotating shaft smaller.

Preferably, the protruding portion is formed to protrude directly outward in the radial direction of the rotating shaft from an edge of the enlarged diameter surface on the bearing side.

In this structure, the protruding portion is formed in such a manner that it protrudes directly outward in the radial direction of the rotating shaft from the edge on the bearing side of the enlarged diameter surface (that is, the maximum outer diameter of the enlarged diameter surface), so that the lubricating oil leakage prevention structure can be made It is more compact in the axial direction of the rotating shaft, the length of the rotating shaft can be reduced, and the overall miniaturization can be realized.

Preferably, the movable part has a sleeve on which the protruding part, the enlarged diameter surface and the first labyrinth seal part are sequentially formed along the axial direction of the rotating shaft, and the stationary The part has a second labyrinth seal part, and the first labyrinth seal part faces the second labyrinth seal part to form a labyrinth seal structure.

In the above structure, since the protrusion, the enlarged diameter surface, and the labyrinth seal are formed on the sleeve, the manufacture is simple.

Preferably, the movable part has a first labyrinth seal part, the stationary part has a second labyrinth seal part, and the first labyrinth seal part is opposed to the second labyrinth seal part to form a labyrinth. In the radial direction of the rotating shaft, the closest distance between the first labyrinth seal part and the second labyrinth seal part is 1 mm or less. Preferably, in a direction perpendicular to the diameter-expanding surface, the distance between the diameter-expanding surface and the stationary part is 1 mm or less.

In the above structure, since the gap of the non-contact sealing part is 1 mm or less, the leakage of lubricating oil can be effectively prevented.

Preferably, a sealing member is provided between the rotating shaft and the boss.

In the above-mentioned structure, since the sealing member is provided, the rotating shaft and the bushing can be integrated to prevent the bushing from idling, and the leakage of lubricating oil from the gap between the rotating shaft and the bushing can be prevented.

Preferably, the first labyrinth seal and the second labyrinth seal are formed by grooves, and a return hole for returning lubricating oil to the bearing side is provided in the groove of the second labyrinth seal. .

In the above structure, by providing the return hole, the lubricating oil can be recovered and reused.

Preferably, the angle of the enlarged diameter surface relative to the rotation axis is 10°-45°.

In the above structure, since the angle of the enlarged diameter surface relative to the rotating shaft is 10°-45°, the sealing effect caused by centrifugal force can be ensured, and the gap between the enlarged diameter surface in the radial direction of the rotating shaft can be made smaller.

Preferably, the diameter-expanding surface faces a surface on the rotating shaft side of the stationary part, one side face of the protruding part faces the bearing, and a side face opposite to the one side face of the protruding part faces the bearing. The side surface on the bearing side of the stationary part is opposite.

The utility model provides a pump, which has the above-mentioned lubricating oil leakage preventing structure of the utility model.

In this structure, since the pump having the above-mentioned lubricating oil leakage prevention structure is used, the sealing performance of the pump can be improved, and the reliability of long-term use can be ensured.

Description of drawings

FIG. 1 is a cross-sectional view showing a pump having a lubricating oil leakage prevention structure according to an embodiment of the present invention.

Fig. 2 is an enlarged view of a lubricating oil leakage prevention structure on the upper side in Fig. 1 .

Fig. 3 is an enlarged view of a lubricating oil leakage prevention structure on the lower side in Fig. 1 .

Symbol Description

1...Pump 2...Rotation shaft 3...Bearing 4...Housing

5...Non-contact seal part 6...Static part 61...Second labyrinth seal part

7...moving part, bushing 71...first labyrinth seal part 72...expanding surface 73...protruding part

8...Sealing part (O-ring) 9...Return hole 10...Oil surface 11...Labyrinth seal

detailed description

Hereinafter, one embodiment of the present invention will be described based on the drawings.

FIG. 1 is a cross-sectional view of a pump having a lubricating oil leakage prevention structure according to an embodiment of the present invention. Fig. 2 is an enlarged view of a lubricating oil leakage prevention structure on the upper side in Fig. 1 . Fig. 3 is an enlarged view of a lubricating oil leakage prevention structure on the lower side in Fig. 1 .

The pump 1 in FIG. 1 is, for example, a pump used in water supply and drainage systems such as domestic, industrial, agricultural, and fire-fighting systems. The pump 1 can be, for example, a double-suction volute pump.

The pump 1 has a housing 4 , and the rotating shaft 2 is rotatably supported by the housing 4 via a bearing 3 . Lubricating oil for lubricating the bearing 3 when the rotating shaft 2 rotates is introduced into the housing 4 through an oil passage. As shown in FIG. 1 , the height of the lubricating oil surface 10 in the housing 4 may be such that a part of the lowermost part of the bearing 3 can be immersed.

A non-contact seal portion 5 for preventing leakage of lubricating oil is provided inside the housing 4 . The non-contact seal portion 5 has a stationary portion 6 fixed to the housing 4 and a movable portion 7 fixed to the rotary shaft 2 .

Here, the manner of fixing the stationary part 6 to the housing 4 may be that the stationary part 6 and the housing 4 are integrally formed, or the stationary part 6 and the housing 4 may be formed separately and fixed to each other by means of engagement, screwing, etc. The stationary portion 6 may be configured as long as it is fixed to the case 4 .

Furthermore, when the rotating shaft 2 rotates, the movable part 7 is fixed to the rotating shaft 2 and rotates together with the rotating shaft 2 relative to the stationary part 6 .

In this embodiment, the movable part 7 is the sleeve 7, but the movable part 7 is not limited thereto, and may include other sealing structures fixed to the rotating shaft 2. An O-ring 8 (sealing member) is provided between the sleeve 7 and the rotating shaft 2 , whereby the sleeve 7 can be fixed to the rotating shaft 2 while preventing the sleeve 7 from idling relative to the rotating shaft 2 .

Referring to FIG. 2 and FIG. 3 , a first labyrinth seal portion 71 , an enlarged diameter surface 72 and a protruding portion 73 are integrally formed on the sleeve 7 sequentially from the end away from the bearing 3 .

The first labyrinth seal portion 71 faces the second labyrinth seal portion 61 provided on the stationary portion 6 to form a labyrinth seal structure. The first labyrinth seal portion 71 and the second labyrinth seal portion 61 are formed by grooves, and more specifically, the first labyrinth seal portion 71 is formed by a plurality of protruding portions protruding outward in the radial direction of the rotary shaft 2 from the sleeve 7 . Formed, the protrusions form grooves between each other. Similarly, the second labyrinth seal portion 61 is formed of a plurality of protruding portions protruding radially inward of the rotary shaft 2 from the stationary portion 6 , and grooves are formed between the protruding portions. The minimum gap H2 between the first labyrinth seal part 71 and the second labyrinth seal part 61 is 1 mm or less. If it is larger than 1 mm, leakage may occur. It is better that the distance is as small as possible within the manufacturing tolerance range, so as to obtain Full sealing effect.

Furthermore, the return hole 9 for returning lubricating oil to the bearing 3 side is opened to the oil groove side through the second labyrinth seal portion 61 . It may be that the return hole 9 is provided in the groove of the second labyrinth seal part 61, and the lubrication entering the groove between the first labyrinth seal part 71 and the second labyrinth seal part 61 by the rotation of the rotating shaft 2 The oil can return to the oil groove through the return hole 9 to realize the repeated utilization of lubricating oil.

The bearing 3 side of the first labyrinth seal part 71 is provided with a diameter-enlarged surface 72 that extends so as to gradually increase in diameter in the radial direction of the rotating shaft 2 toward the bearing 3 side. Preferably, the enlarged diameter surface 72 is a conical surface surrounding the rotating shaft 2 .

The diameter-expanding surface 72 is opposite to the flange protruding from the top end of the stationary part 6. In the direction perpendicular to the diameter-expanding surface 72, the distance H1 between the diameter-expanding surface 72 and the stationary part 6 is 1mm or less. If it is greater than 1mm, Leakage may occur, and the distance should be as small as possible within the allowable range of manufacture to obtain a sufficient sealing effect. In addition, the distance H1 between the diameter-enlarged surface 72 and the stationary portion 6 is kept constant without changing depending on the position.

Moreover, the angle θ of the enlarged diameter surface 72 with respect to the rotating shaft 2 is 10° to 45°. If θ is less than 10°, sufficient centrifugal force effect cannot be obtained, and if θ is greater than 45°, the radial gap will be too large, which is not conducive to Sealing effect.

A protruding portion 73 is formed to protrude directly outward in the radial direction of the rotary shaft 2 from an edge of the enlarged diameter surface 72 on the side of the bearing 3 . That is, the side surface of the protruding portion 73 opposite to the side surface of the stationary portion 6 on the bearing 3 side is formed to protrude from the edge at the maximum outer diameter of the enlarged diameter surface 72 to the radially outer side of the rotating shaft 2 , and the other side of the protruding portion 73 The side face is opposite to the bearing 3 , so that the outer diameter of the protrusion 73 in the radial direction of the rotating shaft 2 is larger than the maximum outer diameter of the enlarged diameter surface 72 in the radial direction of the rotating shaft 2 . That is, when viewed from the bearing 3 side of the protruding portion 73 in the axial direction of the rotating shaft 2 , the outermost edge of the enlarged diameter surface 72 is covered by the protruding portion 73 and cannot be seen.

The height of the outer diameter of the protruding portion 73 is not particularly limited as long as it does not exceed the oil level 10 .

When the rotating shaft 2 rotates, the lubricating oil is driven up by the centrifugal force. Since the protruding portion 73 protrudes beyond the maximum outer diameter of the enlarged diameter surface 72 , leakage of lubricating oil toward the enlarged diameter surface 72 can be sufficiently suppressed. Even if part of the lubricating oil leaks to the enlarged diameter surface 72 side, since the size of the gap of the enlarged diameter surface 72 in the radial direction of the rotating shaft 2 can be suppressed to be small, the centrifugal force can be fully used to make the lubricating oil fling to the housing 4 side. A part of the lubricating oil leaked to the side of the labyrinth seal members 61 and 71 through the enlarged diameter surface 72 can be accommodated in the groove between the first labyrinth seal member 71 and the second labyrinth seal member 61, and a part can pass through The return hole 9 returns to the oil groove, so as to achieve a good sealing effect.

As mentioned above, although one Embodiment of this invention was demonstrated, this invention is not limited to this, Various deformation|transformation is possible within the range of this invention.

For example, in the above-mentioned embodiment, the non-contact seal part having the enlarged diameter surface and the protruding part is provided on one side of the bearing, and another labyrinth seal part 11 is provided on the other side of the bearing. A non-contact seal having an enlarged diameter surface and a protrusion may be provided on both sides of the bearing.

For example, in the above-mentioned embodiment, the enlarged diameter surface, the protruding portion, and the first labyrinth seal portion are integrally formed on the sleeve portion, but the present invention is not limited to this, and the three may be formed separately. In addition, a labyrinth structure may be formed between the second labyrinth seal provided in the stationary part and the rotating shaft, and the first labyrinth seal may be omitted.

For example, in the above-mentioned embodiment, the lubricating oil leakage prevention structure is used for the pump, but it is not limited to this, and may be used in other structures using oil-impregnated lubrication type bearings.

Claims (10)

1. A structure for preventing leakage of lubricating oil, comprising a rotating shaft rotatably supported by a housing via a bearing, and a non-contact seal portion for preventing leakage of lubricating oil, the non-contact seal having a shaft fixed to the housing. The stationary part and the movable part fixed to the rotating shaft are characterized in that, The movable part of the non-contact seal has: an enlarged diameter surface extending in such a manner as to gradually increase in diameter in the radial direction of the rotating shaft toward the bearing side; and a protruding portion that protrudes outward in the radial direction of the rotating shaft on the bearing side of the enlarged diameter surface in a continuous manner around the circumferential direction of the rotating shaft, and A radial outer diameter of the shaft is larger than a maximum outer diameter of the enlarged diameter surface in the radial direction of the rotating shaft. 2. The lubricating oil leakage preventing structure according to claim 1, wherein: The protruding portion is formed to protrude directly radially outward of the rotary shaft from an edge of the enlarged diameter surface on the bearing side. 3. The lubricating oil leakage prevention structure according to claim 1 or 2, wherein the movable part has a bushing, and the protrusions are sequentially formed on the bushing along the axial direction of the rotating shaft. , the enlarged diameter surface and the first labyrinth seal part, the stationary part has a second labyrinth seal part, and the first labyrinth seal part is opposed to the second labyrinth seal part to form a labyrinth seal structure . 4. The lubricating oil leakage preventing structure according to claim 1 or 2, wherein: The movable part has a first labyrinth seal part, the stationary part has a second labyrinth seal part, and the first labyrinth seal part faces the second labyrinth seal part to form a labyrinth seal structure, In the radial direction of the rotating shaft, the closest distance between the first labyrinth seal part and the second labyrinth seal part is 1 mm or less. 5. The lubricating oil leakage prevention structure according to claim 1 or 2, wherein: In a direction perpendicular to the diameter-expanding surface, the distance between the diameter-expanding surface and the stationary portion is 1 mm or less. 6. The lubricating oil leakage prevention structure according to claim 3, wherein: A sealing member is provided between the rotating shaft and the sleeve. 7. The lubricating oil leakage preventing structure according to claim 3, wherein: The first labyrinth seal part and the second labyrinth seal part are formed of grooves, and a return hole for returning lubricating oil to the bearing side is provided in the groove of the second labyrinth seal part. 8. The lubricating oil leakage prevention structure according to claim 1 or 2, wherein: The angle of the expanding diameter surface relative to the rotation axis is 10°-45°. 9. The lubricating oil leakage preventing structure according to claim 1 or 2, wherein: The diameter-expanding surface faces a surface on the rotating shaft side of the stationary part, one side face of the protruding part faces the bearing, and a side face opposite to the one side face of the protruding part faces a side face of the stationary part. The sides of the bearing side are opposite. 10. A pump, characterized in that the pump has the lubricating oil leakage preventing structure according to any one of claims 1 to 9.