JP2018003949A - Bearing lubrication device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bearing lubrication device capable of stabilizing the behavior of a lubrication oil which has passed in a bearing.SOLUTION: A bearing lubrication device includes: a bearing having an inner ring 3a, an outer ring 3b and a rolling element 3c provided between the inner and outer rings; a rotary shaft 5 rotating integrally with the inner ring; an oil supply flow passage 7 formed on one side in the axial direction of the bearing; an oil discharge flow passage 9 which is formed on the other side in the axial direction of the bearing, and whose cross sectional area in the rotary shaft transverse direction is larger than the cross sectional area of the oil supply flow passage; and a flow straightening member 11 mounted on the rotary shaft in the oil discharge flow passage, and including a flow straightening plate 11a provided by being separated by the distance equal to or greater than the width of the bearing in the axial direction of the rotary shaft.SELECTED DRAWING: Figure 1

Description

The present invention relates to a bearing lubrication device, and more particularly to a bearing lubrication device suitable for forced circulation lubrication.

In mechanical systems that are used under high speed, high temperature, and high load conditions, forced circulation lubrication is frequently used to lubricate bearings that support the rotating shaft. This is because the adjustment of the oil supply temperature and the oil supply pressure can be finely adjusted, the reliability is high, and the cooling effect is large. Such forced circulation oil supply is generally composed of an oil tank, a pump, and a piping system.

FIG. 3 is a diagram illustrating a bearing portion of a screw compressor connected to a refrigerant circuit of a refrigeration apparatus described in Patent Document 1. A ball bearing 103 that supports a rotating shaft 105 connected to a compression mechanism and an electric motor (both not shown) is fixedly supported by a housing member 115. Storage chambers 107 and 109 are formed in the housing member 115, and the ball bearing 103 is lubricated by the lubricating oil filling the storage chambers 107 and 109.

The housing member 115 is provided with an oil supply port 123a to which the oil supply pipe 125a of the oil circulation circuit is connected and an oil discharge port 123b to which the oil return pipe 125b is connected. Lubricating oil is supplied from the storage tank (not shown) through the oil supply pipe 125a through the oil supply port 123a to the storage chamber 107, and from the storage chamber 109 through the oil return pipe 125b through the oil discharge port 123b to the storage tank. It is supposed to be returned.

The housing member 115 is provided with a labyrinth seal 127 that seals the storage chamber 109. The labyrinth seal 127 is formed with a through-hole portion 126 through which the rotary shaft 105 passes. The labyrinth seal 127 prevents the lubricating oil in the storage chambers 107 and 109 from leaking outside the housing member 115.

Japanese Patent Application Laid-Open No. 2014-129962

When the bearing is lubricated by forced circulation lubrication as described above, a vortex flow (turbulent flow) is generated in the lubricating oil that passes through the bearing and flows to the outlet side of the bearing in accordance with the bearing rotation. If such a turbulent flow is left, it will lead to a loss of the circulating energy of the lubricating oil, and there is a possibility that the lubricating oil may be discharged from the outlet.

An object of the present invention is to provide a bearing lubrication device that solves the above-described problems and can stabilize the behavior of the lubricating oil that has passed through the bearing.

In order to achieve the above object, a bearing lubricating device according to the present invention is configured as follows. (1) A bearing having an inner ring, an outer ring, and a rolling element provided between the inner and outer rings, a rotating shaft that rotates integrally with the inner ring, and an oil supply passage formed on one axial side of the bearing; Formed on the other axial side of the bearing and having a cross-sectional area in the transverse direction of the rotation axis larger than a cross-sectional area of the oil supply flow path; and attached to the rotary shaft in the oil discharge flow path, And a rectifying member provided with a rectifying plate provided at a distance equal to or greater than the width of the bearing in the axial direction of the rotating shaft. (2) The bearing lubrication device according to (1), wherein the rectifying plate has a plurality of spiral blades closed on a rotation direction side of the rotation shaft and the bearing side.

According to the bearing lubrication device of the present invention, in the oil drainage passage formed in the other axial side of the bearing and having a cross-sectional area in the transverse direction of the rotation axis larger than that of the oil supply passage, The flow of the lubricating oil can be rectified by having the rectifying plate attached to the rotating shaft at a distance greater than the width of the bearing. Further, by providing a difference in the cross-sectional area of the flow path, a pressure difference between the oil supply side and the oil discharge side is generated, and the flow of the lubricating oil can be promoted.

It is sectional drawing of the bearing lubrication apparatus which concerns on this invention. It is the figure which showed taking out only the rectification | straightening member by A arrow view of FIG. It is sectional drawing which shows an example of the conventional bearing lubrication apparatus.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. A bearing lubrication apparatus 1 shown in FIG. 1 includes a bearing 3, a rotating shaft 5, an oil supply passage 7, an oil discharge passage 9, and a rectifying member 11.

The bearing 3 includes an inner ring 3a, an outer ring 3b, and rolling elements (balls) 3c provided between the inner ring 3a and the outer ring 3b. The inner ring 3 a is attached to the rotating shaft 5, and the outer ring 3 b is positioned in the axial direction by a step portion 15 a of the housing 15, and is attached to a predetermined position of the housing 15 by press fitting or the like. Of course, the rolling element may be a roller instead of the ball of the present embodiment.

The rotating shaft 5 is configured to rotate integrally with the inner ring 3a described above. The head 5a on the left side in the figure and a cross-sectional area in a direction transverse to the axis from the head 5a (hereinafter simply referred to as "cross-sectional area") Is a cross-sectional area in the transverse direction of the shaft) and has a shaft portion 5b that is small and fitted to the inner ring 3a.

The oil supply passage 7 is a passage through which supplied lubricating oil flows, and is formed between the housing 15 and the head portion 5a of the rotary shaft 5 on one axial side of the bearing 3 (left side in the drawing). Has been. Although not shown, an oil supply port for the lubricating oil supplied from the lubricating oil storage tank through the oil supply pipe is provided on the left side of the oil supply passage 7 in the drawing.

The oil drain passage 9 is a passage through which the lubricating oil that has passed through the bearing 3 flows. On the other axial side of the bearing 3 (right side in the drawing), the housing 15 and the shaft portion 5b of the rotary shaft 5 are connected. It is formed between. The housing 15 has a larger inner diameter on the oil drainage channel 9 side than the inner diameter on the oil supply channel 7 side, and the rotating shaft 5 is closer to the oil drainage channel 9 side than the outer diameter of the head 5a on the oil supply channel 7 side. Since the outer diameter of the shaft portion 5b is smaller, that is, the difference between the inner and outer diameters is larger on the oil discharge passage 9 side, the cross-sectional area of the oil discharge passage 9 is larger than the cross-sectional area of the oil supply passage 7. Although not shown, a drain port for lubricating oil that is returned to the storage tank through the oil return pipe is provided on the right side of the drain oil passage 9 in the drawing.

The rectifying member 11 is located in the oil drainage flow path 9 and is integrally attached to the shaft portion 5b of the rotating shaft 5, and the side that is radially outward from the core portion 11a and away from the bearing 3 in the axial direction. And a rectifying plate 11b extending in the direction. The left end of the rectifying member 11 in the drawing is in contact with the inner ring 3a, and a rectifying plate 11b is attached to the right end side. The position where the rectifying plate 11b is provided is preferably separated from the bearing 3 by a predetermined distance or more, considering the rectifying action, and is preferably separated by a distance more than the axial width of the bearing 3. As is clear from FIG. 2, the current plate 11 b is a spiral blade that is inclined (twisted) in both the axial direction and the radial direction. The center side of the current plate 11b is continuous with the core 11a in a closed state on the rotation direction side and the bearing 3 side. In addition, the core part and the rectifying plate do not necessarily need to be configured by a single member, and both may be separate.

Next, the operation of the above-described bearing lubrication device 1 will be described.

The lubricating oil that has been pumped into the oil supply passage 7 on the left side of FIG. 1 proceeds to the right side in the drawing and is supplied into the bearing 3, and between the outer ring raceway surface and the ball 3c and between the ball 3c and the inner ring raceway surface. A lubricating oil film is formed between the rotating shaft 5 and the rotating shaft 5 to be able to rotate at a high speed or under a high load. At this time, the lubricating oil moving from the oil supply passage 7 to the bearing 3 to the oil discharge passage 9 is applied to the right side of the bearing 3 in the drawing according to the rotation of the rotary shaft 5 and the inner ring 3a and the revolution of the ball 3c. On the outlet side, a spiral flow is generated.

However, this vortex flow is rectified into a flow in the axial direction of the rotating shaft 5 by colliding with the blades of the rectifying plate 11b. Therefore, since the rotating shaft 5 is rotating, the vortex-like flow is not lost, but the strength of the vortex is weakened by rectification. Thereby, the disturbance of the flow of the lubricating oil in the oil discharge passage 9 is reduced, and the energy loss during the circulation of the lubricating oil can be reduced.

Further, since the cross-sectional area of the oil discharge passage 9 is larger than the cross-sectional area of the oil supply passage 7, the pressure of the oil discharge passage 9 is lowered, and a pressure difference is generated between the two passages. This pressure difference causes a suction effect and promotes the flow of the lubricating oil. Such an accelerated flow of lubricating oil makes it possible to always keep the lubricating surface clean.

In addition, this invention is not limited to embodiment mentioned above, A deformation | transformation, improvement, etc. are possible suitably. For example, as a bearing lubrication apparatus, it can be used not only for a refrigeration apparatus but also for a bearing for a steel rolling apparatus.

DESCRIPTION OF SYMBOLS 3 Bearing 5 Rotating shaft 7 Oil supply flow path 9 Oil drain flow path 11 Rectification member 11a Rectification plate

Claims (2)

A bearing having an inner ring, an outer ring, and a rolling element provided between the inner and outer rings; a rotating shaft that rotates integrally with the inner ring; an oil supply passage formed on one axial side of the bearing; An oil drainage channel formed on the other side in the axial direction and having a cross-sectional area in the transverse direction of the rotation axis that is larger than a cross-sectional area of the oil supply channel; and attached to the rotation shaft in the oil drainage channel; And a rectifying member provided with a rectifying plate provided at a distance equal to or greater than the width of the bearing in the axial direction. 2. The bearing lubrication device according to claim 1, wherein the current plate includes a plurality of spiral blades closed on a rotation direction side of the rotation shaft and the bearing side.

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