JPH0738760Y2 - Lubricating structure of speed reducer using helical gears - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a lubricating structure for a speed reducer using a helical gear.

(Prior Art) As shown in FIG. 3, the structure of the swiveling portion of a hydraulic power shovel that has been conventionally used is such that a hydraulic motor 21 for swiveling is provided in a case 20 provided on the side of an upper pedestal that generally swivels.
The drive shaft 22 is attached in the downward direction, the gear 23 is integrally provided on the shaft 22, and the reduction gear 24 meshing in parallel with the gear 23 is provided with the driven shaft 26 via the spline 25. There is.

If a further reduction ratio is required, use a planetary gear or the like to reduce the speed, and finally swing pinion gear 27
The rotation will be transmitted to. A ring gear 28 meshes with the swing pinion gear 27, and when the hydraulic motor 21 is rotated by the ring gear 28, the swing pinion gear 27 rotates around the ring gear 28 and the upper pedestal rotates.

(Problems to be solved by the invention) In this case, for lubrication of the gears (the helical gears in this embodiment) of the drive shaft and the driven shaft and the lower bearing, lubricating oil is added up to about half the gear width. There is.

Therefore, the bearings and splines above the oil surface are lubricated only by the lubricating oil that is agitated and spattered by the rotation of the gears, and as shown in FIG. Even with oil, it was difficult for oil to reach the bearings above it, and this tended to result in poor lubrication.

Therefore, it is possible to raise the oil level, but this may increase stirring loss due to meshing of the gears and increase the pressure due to the temperature rise of the lubricating oil, which may cause oil leakage from the motor seal. .

Further, it is conceivable to install a forced lubrication pump or the like for lubrication, but there is a problem that this leads to an increase in cost.

In view of this, the present invention eliminates the drawbacks of the prior art by providing a reduction gear lubrication structure using a helical gear that does not require installation of a forced lubrication pump or the like and that facilitates lubrication. It was made for the purpose.

(Means for Solving the Problems) In order to achieve the above object, the present invention supports a drive shaft and a driven shaft that are erected in a housing by upper and lower bearings, and each shaft is provided with a helical gear that meshes with each other. In the reducer,
A lubricating oil passage extending from the lower surface to the upper surface of the bearing is provided above the meshing point of the gear and in the thick portion of the bearing case of the upper bearing on the driven shaft side.

(Operation) With the above configuration, when the driven shaft is rotated by the rotation of the drive shaft, the lubricating oil splashed from between the helical gears by the thrust force can flow from the passage to the upper part of the driven shaft. it can.

(Embodiment) Hereinafter, the present invention will be described with reference to an embodiment shown in FIGS. The lubricating structure of the speed reducer using the helical gears according to the present invention supports the drive shaft 2 and the driven shaft 3 which are erected in the housing 1 by the upper and lower bearings 4, 4, 5 respectively. In a reduction gear provided with helical gears 6 and 7 that mesh with each other in 2 and 3, the thick portion of the bearing case 8 of the upper bearing 5 on the driven shaft 3 side, just above the meshing point of the gears 6 and 7. 9, a lubricating oil passage 10 is provided which extends from the lower surface to the upper surface of the bearing 5.

That is, the drive shaft 2 externally fitted to the shaft of the turning hydraulic motor 11 mounted in the downward direction is erected inside the housing 1 provided on the upper mount side (not shown). The helical gear 6 is integrally provided in the. The speed reducing gear 7 that meshes in parallel with the helical gear 6 is provided with the driven shaft 3 via a spline 12. If a further reduction ratio is required, the planetary gear mechanism 13 is used to reduce the speed, and finally the swing pinion gear 14 provided at the bottom is used.
The rotation will be transmitted to.

A ring gear 15 meshes with the swing pinion gear 14, and when the hydraulic motor 11 rotates as a result, the swing pinion gear 14 rotates around the ring gear 15 and the upper mount rotates. In the figure, L indicates the oil level.

Next, when the helical gears 6 and 7 meshing with each other are in the rotation direction as shown by the arrows in FIG. 2, the lubricating oil at the meshing points of the gears 6 and 7 is splashed upward by the thrust force of the helical gears. In the present invention, since the passage 10 is provided in the thick portion 9 of the bearing case 8 located right above the meshing point, a part of the splashed oil passes through the passage 10 and the bearing 5 and the driven shaft. The oil flows to the upper end surface of No. 3 and falls into the bearing 5 and the spline 12 and returns to the oil surface of the lubricating oil below.

Therefore, the bearing 5 and the spline 12 are continuously lubricated.

In this embodiment, the lubrication when the driven shaft 3 and the cutting edge of the helical gear 7 are relatively distant from each other has been described.
When the blades are close to each other like the cutting edge of the helical gear 6, the bearing 4 is located above the oil splashed by the meshing of the gears 6 and 7, so that lubrication is sufficient without the above-mentioned measures. You can do it.

Further, although the present embodiment shows the case of being applied to the turning mechanism of the power shovel, it is suitable for general purpose and is not limited to the power shovel.

(Effect of the Invention) As described above, according to the present invention, the receiving passage for the lubricating oil splashed by the thrust force at the meshing point of the helical gears is provided in the thick portion of the bearing case. It is possible to solve the problem by using the method described above, and an excellent effect can be achieved with an extremely simple structure.

[Brief description of drawings]

FIG. 1 is a sectional view of a lubricating structure of a speed reducer using a helical gear according to the present invention, and FIG. 2 is a perspective view showing a splashing state of lubricating oil due to meshing of the helical gears in FIG.
The figure is a sectional view of a speed reducer using a conventional helical gear. 1 ... Housing, 2 ... Drive shaft, 3 ... Driven shaft, 4,5 ... Bearing, 6,7
... helical gear, 8 ... bearing case, 9 ... thick part, 10 ... passage, 11 ... hydraulic motor, 12 ... spline, 13 ... planetary gear mechanism, 14 ... swing pinion gear, 15 ... ring gear, L ...
Oil surface.

Claims (1)

[Scope of utility model registration request] 1. A speed reducer in which a drive shaft and a driven shaft erected in a housing are supported by upper and lower bearings, and each shaft is provided with a helical gear that meshes with each other. Above the meshing point of the gears, A lubricating structure for a speed reducer using a helical gear, characterized in that a lubricating oil passage extending from the lower surface to the upper surface of the bearing is provided in a thick portion of the bearing case of the upper bearing on the driven shaft side.