JP6432389B2 - Non-contact type sealing device in a gear device for a railway vehicle - Google Patents

Description

  The present invention relates to a non-contact seal device in a gear device for a railway vehicle that transmits driving force generated by an electric motor to wheels.

  As shown in FIG. 3, the railway vehicle transmits the driving force generated by the electric motor to the small gear shaft 2 of the gear device 1 through the shaft coupling and engages with the small gear 3 formed on the small gear shaft 2. It is transmitted to the wheel attached to the axle 5 via the gear 4 and travels.

  In the gear device 1, the lubricating oil 7 in the casing 6 in which the small gear 3 and the large gear 4 are housed is swept up by the rotation of the large gear 4, so that the meshing portion A of the large gear 4 and the small gear 3 and the axle 5 The bearings 8 and 9 supporting the small gear shaft 2 are lubricated.

  However, in order to supply sufficient lubricating oil 7 to the bearings 8 and 9, it is necessary to secure a sufficient amount of lubricating oil 7 in the casing 6. At this time, it is necessary that the lubricating oil 7 supplied to the bearings 8 and 9 lubricates the bearings 8 and 9 and then returns to the inside of the casing 6 to prevent leakage from the bearings 8 and 9 to the outside.

  Therefore, in the gear device 1 for a railway vehicle, a shaft seal device is provided in a portion where the small gear shaft 2 and the axle shaft 5 penetrate from the casing 6 and project.

  The shaft seal device of a rotating shaft such as a transport machine is classified into a non-contact seal in which the rotating shaft and the casing portion do not contact, and a contact seal that ensures a sealing function by contacting the rotating shaft and the casing through a resin member or the like. Both are used properly according to the usage environment of the apparatus.

  In a railway gear device, a non-contact seal is employed as a shaft seal device for a small gear shaft or an axle.

  However, in the non-contact seal, when a pressure difference occurs between the inside and outside of the casing, a gas flow is generated in the flow path of the non-contact seal, and the lubricating oil remaining inside is transported by shear due to the gas flow and is transferred to the outside of the casing. Leakage problems may occur.

  The cause of the pressure difference between the inside and outside of the casing is that the pressure rises due to a rise in the internal temperature of the casing, the pressure drop outside the casing due to entry into the tunnel or the passing of trains, etc., the pressure drop due to the rotational centrifugal force of the rotary shaft coupling member Etc. are considered.

  To avoid the lubricating oil leakage trouble, as shown in FIG. 4, the labyrinth seal is provided with a multi-stage labyrinth flow path 10 to lengthen the passage connecting the inside and the outside of the casing 6 to enhance the sealing effect. Is often adopted.

  Further, as shown in FIG. 5, by providing a projection called a slinger 11 on the small gear shaft 2 or the axle 5, the lubricating oil that has flowed out along the small gear shaft 2 or the axle 5 is shaken off by centrifugal force, and the lubricating oil is removed. A structure for returning to the casing 6 is employed.

  In a railway vehicle gear device, for example, as shown in FIGS. 6 and 7, lubrication from the inside of the casing 6 is performed by a labyrinth seal provided with both the multi-stage labyrinth flow path 10 shown in FIG. 4 and the slinger 11 shown in FIG. Oil leakage is suppressed (see, for example, Patent Documents 1 and 2).

  However, the basic design guideline of providing both the multi-stage labyrinth flow path and the slinger alone may cause the lubricating oil to leak, and the leakage mechanism is unknown, so that the fundamental solution has not been reached.

Japanese Patent No. 5131968 Japanese Patent Publication No. 6-63573

  The problem to be solved by the present invention is that in the case of a non-contact type sealing device in a conventional railway vehicle gear device, it is not possible to prevent leakage of lubricating oil simply by providing a multi-stage labyrinth passage and a slinger together. It may be sufficient.

  In order to further improve the sealing performance of the non-contact type sealing device in the railway vehicle gear device, the inventors conducted a detailed visual analysis by performing numerical analysis described later on the gas flow and oil droplet flow in the labyrinth seal.

  As a result, as shown in FIG. 6, the space 14, the narrow gap 12 b, the large space 13, and the narrow gap 12 a (labyrinth) are formed from the bearing 9 side to a region extending from the bearing 9 of the small gear shaft 2 or axle to the outside of the casing 6. 8), and the outlet 12bb of the narrow gap 12b and the inlet 10a of the labyrinth passage 10 are opposed to each other, as shown in FIG. The large space 13 is short-circuited from the gap 12 b and flows into the labyrinth flow path 10.

  Further, as shown in FIG. 7, even when the radial position of the small gear shaft 2 is different between the outlet 12bb of the narrow gap 12b and the inlet 10a of the labyrinth passage 10, the size of the large space 13 is small. If it is insufficient, the large space 13 becomes a part of the flow path of the gas flow as shown in FIG. 9, and the oil droplets riding on the gas flow do not stay in the large space 13 and enter the labyrinth flow path 10. Flowing.

  That is, it was found that the amount of oil particles trapped in the large space 13 was insufficient and the overall oil sealing performance was insufficient. 6 to 9, reference numeral 15 denotes a trajectory of the flow of oil particles, 16 denotes a bearing lid, and 17 denotes a sleeve on the small gear shaft side.

  The inventors have found a guideline for quantitatively evaluating the seal performance by numerically analyzing the gas flow and oil droplet flow in the labyrinth seal and performing detailed visualization analysis, and a new non-contact that further improves the seal performance. Type seal device was completed.

The present invention
In order to further improve the sealing performance of the non-contact type sealing device in a railway vehicle gear unit,
A non-contact type sealing device for a railway vehicle gear device in which a small gear formed on a small gear shaft connected to an electric motor via a shaft coupling and a large gear attached to an axle are meshed and accommodated in a casing. And
A narrow gap, a space, and a narrow gap are repeatedly provided one or more times in at least one of a region from the outside of the casing to the bearing of the small gear shaft and a region from the outside of the casing to the bearing of the axle.
When viewed from the bearing side, the exit of the narrow gap to the space and the entrance of the narrow gap from the space are at different positions in the radial direction of the small gear shaft or axle, and the small gear shaft or axle. Open in the axial direction of
In the space, the radial direction length of the small gear shaft or the axle from the inlet of the narrow gap to the outer peripheral side end surface of the space, and the maximum length in the axial direction of the small gear shaft or the axle are determined as the width of the narrow gap. Greater than the radial length between the outlet and the inlet of the narrow gap ;
A slinger projecting from the inlet is provided on the small gear shaft or axle center side of the narrow gap inlet, and oil droplets flowing out from the narrow gap outlet flow to the outer peripheral side of the space. The main feature is that it makes a round along the inner wall .

  In the present invention, in the space, the radial length of the small gear shaft or the axle from the narrow gap inlet to the outer peripheral end surface of the space is set to 0.3 of the radial length between the narrow gap outlet and the narrow gap inlet. Further, the maximum length in the axial direction of the small gear shaft or the axle in the space is set to 0.5 times or more of the radial length between the narrow gap outlet and the narrow gap inlet.

  Accordingly, the oil droplets riding on the gas flow flow from the narrow gap to the outer peripheral side of the space and do not short-circuit the space from the narrow gap and flow into the narrow gap.

  In the present invention, since the oil droplets riding on the gas flow flow from the narrow gap to the outer periphery side of the space and sufficiently stay in the space, the amount of oil particles trapped is increased and leakage to the outside of the casing can be prevented.

It is sectional drawing of the principal part of the non-contact-type sealing device in the gear apparatus for railway vehicles of this invention. It is the figure which showed the locus | trajectory of the flow of the oil particle in the non-contact-type sealing device shown in FIG. 1 by the numerical flow analysis. It is sectional drawing of the gear apparatus for railway vehicles of an oil bath lubrication type. It is a figure explaining the labyrinth seal which provided the multistage labyrinth flow path. It is a figure explaining the seal | sticker which provided the slinger. It is sectional drawing of the principal part of the non-contact-type sealing apparatus in the conventional gear apparatus for rail vehicles. It is sectional drawing of the principal part of the non-contact-type sealing apparatus in the other conventional gear apparatus for rail vehicles. It is the figure which showed the locus | trajectory of the flow of the oil particle in the non-contact-type sealing device shown in FIG. 6 by the numerical flow analysis. It is the figure which showed the locus | trajectory of the flow of the oil particle in the non-contact-type sealing device shown in FIG. 7 by the numerical flow analysis.

  An object of the present invention is to further improve the sealing performance of a non-contact type sealing device in a railway vehicle gear device.

  Then, the object is to set the radial length of the small gear shaft or the axle in the space to the narrow gap inlet and the outer peripheral end surface of the space to 0 in the radial length between the narrow gap outlet and the narrow gap inlet. .3 times or more, and the maximum axial length of the small gear shaft or axle in the space is 0.5 times or more of the radial length between the narrow gap outlet and the narrow gap inlet. It was realized.

An embodiment of the present invention will be described below with reference to FIGS.
FIG. 1 is a cross-sectional view of a main part of a non-contact type sealing device in a railway vehicle gear device according to the present invention, and FIG. 2 shows a trajectory of oil particle flow in the non-contact type sealing device shown in FIG. It is a figure. 1 and 2, the same reference numerals as those in FIGS. 3 to 9 denote the same or corresponding parts, and a detailed description thereof will be omitted.

  As illustrated in FIG. 1, the gear device for a railway vehicle according to the present invention includes, for example, a narrow gap 12 a (labyrinth flow path) in order from the outside of the casing 6 in a region extending from the bearing 9 of the small gear shaft 2 to the outside of the casing 6. 10), a large space 13, a narrow gap 12b, and a space 14 are provided in the axial direction of the small gear shaft 2.

  Then, when viewed from the bearing 9 side, the outlet 12bb of the narrow gap 12b to the large space 13 and the inlet 10a of the labyrinth channel 10 from the large space 13 are the length of L1 in the radial direction of the small gear shaft 2. The small gear shaft 2 is opened in the axial direction.

  At this time, in the present invention, in the large space 13, the radial direction length L2 of the small gear shaft 2 from the inlet 10a of the labyrinth channel 10 to the outer peripheral side end surface of the large space 13 is 0.3 times or more of the length L1. And the maximum length L3 of the small gear shaft 2 in the axial direction is greater than 0.5 times the length L1.

  In the example of FIG. 1, the axial length L4 of the small gear shaft 2 between the outlet 12bb of the narrow gap 12b and the inlet 10a of the labyrinth passage 10 in the large space 13 is larger than the inlet 10a portion of the labyrinth passage 10. The thing provided with the standing wall 10b of long height is shown.

  In the present invention having the above-described configuration, as shown in FIG. 2, the oil droplets that have flowed out of the gas flow and flowed out from the outlet 12bb of the narrow gap 12b flow to the outer peripheral side of the large space 13 and make one round along the inner wall of the large space 13. However, the large space 13 is not short-circuited from the narrow gap 12 b and does not flow into the labyrinth flow path 10.

  In other words, in the present invention, oil droplets riding on the gas flow flow from the narrow gap 12b connecting the space 14 and the large space 13 to the outer peripheral side of the large space 13 and sufficiently stay in the large space 13, so that the oil particles are captured. The amount increases and leakage of the lubricating oil to the outside of the casing 6 can be effectively prevented.

  The numerical flow analysis for obtaining the oil particle flow locus 15 shown in FIGS. 2, 8, and 9 was performed using Fluent, which is one of general-purpose CFD (computational fluid dynamics).

  Specifically, the labyrinth seal structure shown in FIGS. 1, 6, and 7 is expressed by an axisymmetric three-dimensional calculation model, the moving wall boundary condition is set on the wall surface of the sleeve 17 on the small gear shaft side, and the stationary wall surface is set on the other wall surfaces. Boundary conditions were set.

  Then, by setting the atmospheric pressure of the space 14 provided with the bearing 9 higher than the atmospheric pressure, the casing 6 passes through the space 14, the narrow gap 12 b, the large space 13, the labyrinth flow path 10, and the narrow gap 12 a from the bearing 9. The velocity field of the gas flow flowing out to the outside was calculated.

  Further, a group of fine particles simulating oil particles is suspended in the calculated gas flow, and a trajectory 15 of the flow is calculated. From this result, the oil particles are communicated with the space 14 from the inlet 12ba of the narrow gap 12b. The time until leakage to the outside (hereinafter referred to as residence time) was measured.

  As a result, in the case of the dimensions (mm) shown in FIG. 1 and FIGS. 6 and 7, assuming that the residence time of the conventional non-contact type sealing device shown in FIG. The residence time of the contact seal device was 1.5.

  On the other hand, the residence time of the non-contact type sealing device of the present invention shown in FIG. 1 is 4.5, 4.5 times that of the conventional non-contact type sealing device shown in FIG. The residence time was 3.0 times that of other non-contact type sealing devices.

  In the conventional non-contact type sealing device shown in FIG. 6, as shown in FIG. 8, the oil particles flowing out from the space 14 through the narrow gap 12 b into the large space 13 are almost directed toward the labyrinth channel 10. This is because the effect of capturing the oil particles in the large space 13 can hardly be expected because it flows linearly.

  Further, in the other conventional non-contact type sealing device shown in FIG. 7, as shown in FIG. 9, oil particles that have flowed out of the narrow gap 12 b into the large space 13 enter the large space 13 on the way to the labyrinth flow path 10. This is because once the large space 13 is captured, the large space 13 is insufficient in size, so that the large space 13 itself becomes a part of the flow path, and the effect of capturing the oil particles in the large space 13 can hardly be expected. .

  On the other hand, in the case of the non-contact type sealing device of the present invention shown in FIG. 1, the oil particles that have flowed into the large space 13 flow toward the outer side in the radial direction of the small gear shaft 2 and then the large space 13. As a result of the oil particles sufficiently staying in the large space 13 around the inner wall surface, the amount of oil particles trapped in the large space 13 is increased, and the sealing performance is improved.

  In order to confirm the effects of the present invention, a gear device having the non-contact type sealing device shown in FIGS. It was determined whether or not to do.

  As a result, in the case of the conventional non-contact type sealing device shown in FIGS. 6 and 7, oil leakage occurred, but in the case of the non-contact type sealing device of the present invention shown in FIG. 1, no oil leakage occurred. .

  The present invention is not limited to the above example, and it goes without saying that the embodiments may be changed as appropriate within the scope of the technical idea described in each claim.

  For example, in the embodiment shown in FIG. 1, the inlet 10 a portion of the labyrinth channel 10 is higher than the axial length L 4 of the small gear shaft 2 between the outlet 12 bb of the narrow gap 12 b and the inlet 10 a of the labyrinth channel 10. Although the standing wall 10b is provided, the standing wall 10b may not be provided.

  The present invention described above can be applied to any gear device, not limited to a gear device for a railway vehicle.

DESCRIPTION OF SYMBOLS 1 Gear apparatus 2 Small gear shaft 3 Small gear 4 Large gear 5 Axle 6 Casing 7 Lubricating oil 8,9 Bearing 10 Labyrinth flow path 10a Inlet 10b Standing wall 11 Slinger 12a Narrow gap 12b Narrow gap 12bb Outlet 13 Large space 14 Space

Claims (3)

A non-contact type sealing device for a railway vehicle gear device in which a small gear formed on a small gear shaft connected to an electric motor via a shaft coupling and a large gear attached to an axle are meshed and accommodated in a casing. And
A narrow gap, a space, and a narrow gap are repeatedly provided one or more times in at least one of a region from the outside of the casing to the bearing of the small gear shaft and a region from the outside of the casing to the bearing of the axle.
When viewed from the bearing side, the exit of the narrow gap to the space and the entrance of the narrow gap from the space are at different positions in the radial direction of the small gear shaft or axle, and the small gear shaft or axle. Open in the axial direction of
In the space, the radial length of the small gear shaft or the axle from the narrow gap inlet to the outer peripheral end surface of the space is set to 0. 0 of the radial length between the narrow gap outlet and the narrow gap inlet. 3 times or more, and further, the maximum axial length of the small gear shaft or the axle in the space is 0.5 times or more of the radial length between the narrow gap outlet and the narrow gap inlet ,
A slinger projecting from the inlet is provided on the small gear shaft or axle center side of the narrow gap inlet, and oil droplets flowing out from the narrow gap outlet flow to the outer peripheral side of the space. A non-contact type sealing device in a gear device for a railway vehicle, characterized in that it makes one round along an inner wall .   2. A standing wall higher than the axial length of the small gear shaft or the axle between the outlet of the narrow gap and the inlet of the narrow gap is provided at the inlet of the narrow gap in the space. The non-contact-type sealing device in the gear apparatus for railway vehicles described in 1.   3. The non-contact type sealing device for a railway vehicle gear device according to claim 1, wherein the narrow gap provided outside the casing from the space includes a labyrinth flow path. 4.

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