JPH09152020A - Gear device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make an oil drain hole outlet to be negative pressure compared with the outside of a labyrinth so as to prevent oil leakage from the labyrinth by providing a recessed part on the lower part of a circular ring, providing a hole penetrating through the inside of the wall of a gear box from the contact part with the oil drain hole outlet to the recessed part, and making the recessed part as the outlet of the oil drain hole. SOLUTION: A recessed part 12 is provided on the lower part of a circular ring 3a so as to provide a hole in the axial direction from the interior of a gear box 3. A cutout 15 is provided on the contact part of the gear box 3 with the outlet of an oil drain hole 11 of the spigot face, and a hole 16 penetrating from the cutout 15 through the inside of the wall of the gear box 3 to the recessed part 12 is provided. The outlet of the oil drain hole of the labyrinth of a gear device is provided in the vicinity of the rim side face 2a of a rotating large gear 2 in this way. Hereby, the pressure of the outlet of the oil drain hole of the labyrinth can be made to be negative pressure by rotation of the large gear 2, oil stayed in the labyrinth can be smoothly returned to the inside of the gear box 3 through the oil drain hole 11, and hence oil leakage can be prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle drive gear device, and more particularly to a structure of an oil drain hole of a shaft sealing device.

[0002]

2. Description of the Related Art An example of a conventional oil bath lubrication type gear device will be described with reference to the drawings. FIG. 3 is a cross-sectional view of an essential part showing an example of a conventional oil bath lubrication type gear device. 1 is a small gear, 2 is a large gear, 3
Is a gear box that seals the large gear 2 and the small gear 1 inside and stores the lubricating oil 4 up to the position where a part of the large gear 2 is immersed in the bottom thereof. Reference numerals 5 and 6 denote bearings, and the small gear 1 and the large gear 2 are supported by the gear box 3 via bearings 5 and 6, respectively, and rotate. The lubricating oil 4 is scraped up by the rotation of the large gear 2 and lubricates the meshing surfaces of the small gear 1 and the large gear 2 and the bearings 5, 6. Here, at high speed rotation, the lubricating oil 4 is disturbed in the gear box 3 and the temperature rise of the gear device becomes excessive. As a countermeasure, as shown in FIGS. 3 and 4, there is also a gear device in which an annular ring 3a is formed on the inner wall of the gear box 3 close to the rim side surface 2a of the large gear 2.

FIG. 4 is a cross-sectional view of the main part at the center of the large gear shaft in FIG. 3, and the same reference numerals as those in FIG. 3 denote the same parts. FIG.
2, the lubricating oil (not shown) lifted up by the large gear 2 smoothly flows through the path 7 surrounded by the inner peripheral wall surface of the gear box 3, the rim side surface 2a of the large gear 2 and the ring 3a, and excessive disturbance is caused. Is suppressed. Here, a labyrinth shaft seal device will be described with reference to FIG. The axle 9 is rotatably supported on the gear box 3 by a lid 8 via a bearing 6. A labyrinth forming a shaft sealing device is formed on the lid 8 together with an oil drainer 10 fitted to an axle 9, and a lubricating oil (not shown) accumulated in the labyrinth is returned to the inside of the gear box 3 by a lower oil drain hole 11.
The present gear device is used for driving a vehicle, and the outside of the gear device, that is, the outside of the labyrinth receives a traveling wind, whereby negative pressure acts.

[0004]

The pressure at the outlet of the oil drain hole of the conventional labyrinth structure is equal to the internal pressure of the gear box and is almost atmospheric pressure. Here, in a situation where the outside of the labyrinth has a negative pressure due to the traveling wind, the lubricating oil accumulated in the labyrinth may not be returned to the inside of the gear box from the oil drain hole, but may be sucked into the outside air and leak from the labyrinth. The present invention was devised in view of the above-mentioned points, and an object thereof is to provide a gear device that prevents oil leakage from a labyrinth.

[0005]

[Means for Solving the Problems] That is, a means for achieving the object is a gear box in which an annular ring, which is adjacent to the rim side surface of a large gear whose rotation axis is horizontal, is projected from the inner wall surface of the gear box. In the gear device using, a recess is provided in the lower part of the ring so as to make a hole in the gear box from the inside. A labyrinth waste oil hole outlet, which is configured as a lid that rotatably supports the axle via a bearing, is provided on the inlay surface of the lid with the gear box. A hole is formed by penetrating the inside of the wall of the gear box from the contact portion of the spigot surface of the gear box with the outlet of the oil drain hole to the recessed portion, and the recessed portion serves as the outlet of the oil drain hole. Thus, the labyrinth drainage hole outlet of the gear device is formed near the rim side surface of the rotating large gear.

[0006]

In the labyrinth drainage hole according to the present invention, the outlet is located in the vicinity of the rim side surface of the large gear, so that the position of the outlet can be lowered as compared with the conventional case. It can be negative pressure. For example, 300
Under the floor of a railway vehicle running at Km / h, a running wind of v1 = 30 m / S is measured, and this acts as a negative pressure outside the labyrinth of the gear train. Here, the peripheral speed of the rim portion of the gear device is v2 = 45 m / S, and assuming that this is the speed of the liquid at the outlet of the oil drain hole, the fluid is also air (density ρ = 1.2 kg / cubic meter). Assuming that the pressures p1 and p2 at the outside of the labyrinth and the outlet of the oil drain hole are: p1 (v1 = 30m / S) = 1 / 2ρ.v1.v1 = 54mm
Aq p2 (v2 = 45m / S) = (1/2) ρ ・ v2 ・ v2 =
It becomes 122mmAq, and the pressure becomes lower than that of the atmosphere. Therefore, the pressure at the oil drain hole outlet p2 is 68 more than the pressure p1 outside the labyrinth.
mmAq Negative pressure. The liquid velocity at the oil drain hole outlet is v2 = 45
Although it cannot be m / S, the liquid is an oil mist having a density higher than that of air, and the approximate value is about this value.
As described above, the outlet of the oil drain hole can be made to have a relatively negative pressure from the outside of the labyrinth, the oil in the oil drain hole can easily return to the gear box, and the oil leakage from the labyrinth can be prevented.

[0007]

Embodiments of the present invention will be described in detail below with reference to the drawings. FIG. 1 is a sectional view of an essential part showing an embodiment of the present invention similar to FIG. 4, and FIG. 2 is a side view thereof. In FIG. 1, in a gear device using a gear box 3 in which an annulus 3a adjacent to a rim side surface 2a of a large gear 2 is projected from an inner wall surface of the gear box, a gear box 3 is provided below the annulus 3a from inside the gear box 3. A recess 12 is provided so as to receive the hole in the axial direction. While the labyrinth oil drain hole 11 formed in the lid 8 that rotatably supports the axle 9 on the gear box 3 via the bearing 6 is stopped by the plug 13 on the inner surface of the gear box,
A notch 14 is provided in the spigot portion of the lid 8 with the gear 3 and the outlet of the oil drain hole 11 is provided on the spigot surface of the lid 8 with the gear box 3. A similar notch 15 is also provided at the contact portion of the spigot surface of the gear box 3 with the outlet of the oil drain hole 11, and a hole 16 is bored from the notch 15 to the recess 12 through the inside of the wall of the gear box 3. In this way, the labyrinth oil drain hole outlet of the gear device is formed near the rim side surface of the rotating large gear. In FIG. 2, an oil drain hole 11 machined in the lid 8, a notch 14 machined in the spigot part, a recess 12 machined in the ring 3a of the gear box 3 and a notch 15 in the spigot part, and a hole penetrating through the wall. Shows 16.

[0008]

As described above, according to the present invention, the pressure at the oil drain hole outlet of the labyrinth can be made negative by the rotation of the large gear. As a result, even if the pressure outside the labyrinth becomes a negative pressure due to the running wind like a vehicle drive gear,
The oil that collects in the labyrinth can be smoothly returned to the inside of the gear box through the oil drain hole, and it is very effective in preventing oil leakage. In addition, since the outlet of the oil drain hole can be set near the rim of the large gear by using the ring along the rim side surface of the large gear, a new protrusion does not occur with respect to the rotation of the large gear, and It can be prevented from becoming a new heat source.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of a gear device according to the present invention.

FIG. 2 is a side view of a main part thereof.

FIG. 3 is a sectional view of an essential part showing an example of a conventional oil bath lubrication type gear device.

FIG. 4 is a cross-sectional view of a main part at the center of the large gear shaft.

[Explanation of symbols]

 1 Small Gear 2 Large Gear 2a Rim Side 3 Gear Box 3a Ring 4 Lubricating Oil 5 Bearing 6 Bearing 7 Path 8 Lid 9 Axle 10 Oil Drainer 11 Oil Drain 12 Dent 13 Plug 14 Notch 15 Notch 16 Hole

Claims (1)

[Claims] 1. A gear device using a gear box in which a ring close to the rim side surface of a large gear protrudes from an inner wall surface of the gear box, wherein a recess is provided in the lower part of the ring, and the inside of the gear box is formed from this recess. A gear unit characterized in that a hole is axially bored through the side wall of the gear unit, and the recessed portion is used as an outlet of an oil drain hole of a labyrinth of the gear unit.