JPH0621629B2 - Lubrication structure of transfer - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a transfer of a four-wheel drive vehicle that can switch between two-wheel drive and four-wheel drive, and more particularly to a lubrication structure of the transfer.

(Prior Art) Conventionally, a switching mechanism known as a transfer for switching between this type of four-wheel drive (hereinafter referred to as 4WD) and two-wheel drive (hereinafter referred to as 2WD) is shown in FIG.
In the figure, a main drive shaft 4 which is composed of a chain case 1 and a gear case 2 and to which a driving force from an engine is transmitted, and a main shaft 5 extending toward a propeller shaft side are rotatably supported by bearings. . A main drive gear 7 that meshes with a counter gear 6 is integrally formed on the main drive shaft 4, and the counter gear 7 also meshes with a low speed gear 8 that is relatively rotatably mounted on the main shaft 5 via a needle bearing. Then, the rotational force of the main drive shaft 4 is transmitted to the low speed gear 8 via the main drive gear 7 and the counter gear 6. A hub 9 is spline-fitted to the main shaft 5, and a coupling sleeve 10 is slidably fitted to the hub 9.

Here, when the coupling sleeve 10 is in the neutral position as shown in the figure, the main shaft 5 does not rotate because the rotational force of the main drive shaft 4 is not transmitted. On the other hand, when the coupling sleeve 10 is moved to mesh with the clutch gear 7a of the main drive gear 7, the rotational force of the main drive gear 7 is transmitted to the main shaft 5 via the coupling sleeve 10 and the hub 9, and the main shaft 5 5 rotates at high speed. On the other hand, when the coupling sleeve 10 is moved to mesh with the clutch gear 8a of the low speed gear 8, the rotational force of the main drive gear 7 is transferred to the main gear via the counter gear 6, the low speed gear 8, the coupling sleeve 10 and the hub 9. While being transmitted to the shaft 5, the main shaft 5 is rotated at a low speed by the reduction gear ratio set by the counter gear 6.

Next, in the chain case 1, the switching gear 13 fitted to the main shaft 5 by a spline and the main shaft 5
A synchro mechanism having a sprocket 11 rotatably mounted via a needle bearing and a coupling sleeve 12 slidably engaged with the sprocket 11 by a spline is provided to move the coupling sleeve 12. When meshed with the switching gear 13, both the switching gear 13 and the sprocket 11 rotate together with the main shaft 5. The drive shaft 14 is a shaft for transmitting a driving force to two wheels that are driven only in the case of 4WD traveling, and includes a sprocket 15 and a sprocket 11 that are integrally fixed to the drive shaft 14.
A chain 16 is installed between the two.

Here, when the coupling sleeve 12 is moved to mesh with the switching gear 13, the rotational force of the main shaft 5 is transmitted to the sprocket 11 via the switching gear 13 and the coupling sleeve 12, and the sprocket 15 accordingly.
And the chain 16 rotates, so the drive shaft 1
The driving force of the engine is transmitted to the two wheels that are interlocked with 4 and the other two wheels that are constantly driven by the main shaft 5, resulting in a 4WD traveling state. On the other hand, if the coupling sleeve 12 is meshed only with the sprocket 11 as shown in the figure, the driving force from the engine is not transmitted to the sprocket 11, so that only the two wheels that are always linked with the main shaft 5 are driven and the 2WD It becomes a running state.

Next, the lubrication structure of the chain case 1 will be described. The sprocket 11 has a plurality of through holes 17 penetrating from the outer diameter to the main shaft 5 side, and the lubrication scattered in the chain case 1 during operation of the chain case 1 is described. Oil through hole 1
Supplying to the needle bearing through 7 lubricates the moving parts of the sprocket 11.

(Problems to be Solved by the Present Invention) However, in such a transfer lubrication structure, since the through holes 17 are simply formed in the radial direction of the sprocket 10, the running state of 2WD is particularly important. In the above, since the sprocket 11 does not rotate and the main shaft 5 rotates at high speed, the amount of lubricating oil may be insufficient depending on the direction of the through hole 17 of the sprocket 11 in the stopped state, and the needle bearing or the like may be seized. .

(Means for Solving Problems) The present invention has been made in view of the above problems of the prior art, and provides a transfer lubricating structure capable of supplying sufficient lubricating oil to the bearing portion of the sprocket. In order to achieve this purpose, a seal bearing provided on the end face side of the sprocket that is relatively rotatably mounted on the main shaft through the bearing is provided with a partition plate for forming an oil sump, and a gear case is provided. The lubricating oil collected by the oil gutter provided in 2 is supplied to the oil sump, and the lubricating oil collected in the oil sump is supplied to the bearing portion of the sprocket to ensure sufficient lubrication. It is characterized by

(Embodiment) An embodiment of a transfer lubricating structure according to the present invention will be described below with reference to the drawings. In FIG. 1, a one-sided seal bearing 25 is provided on one end face side of the sprocket 11, and a concave step portion 18 is formed in an annular shape on the end face side of the sprocket. A plurality of through holes 20 are formed. Between the concave step portion 18 of the sprocket 11 and the inner wall of the chain case 1, a substantially annular partition plate 21 having an inner wall inclined toward the axial direction of the main shaft 5 is interposed, and the concave step portion 1
The portion where 8 and the partition plate 21 contact each other is sealed, and the portion surrounded by the recessed step portion 18, the partition plate 21, and the seal bearing 25 serves as an oil sump 22. A through hole 23 penetrating from the inside of the partition plate 21, that is, from the oil sump 22 side to the gear case 2 side is formed in the gear case 2 and the bearing retainer 26 and communicates with an oil gutter 24 provided in the gear case 2. Next, the operation of such a lubricating structure will be described. First, the lubricating oil scattered in the gear case 2 by the rotation of the gear in the gear case 2 is collected in the oil gutter 24, is further stored in the oil sump 22 through the through hole 23, and is then stored through the plurality of through holes 20. It is supplied to the bearing 19. In this way, the lubricating oil is stored in the oil sump 22.
After being collected into the needle bearing 19, it is supplied to the needle bearing 19 side, so that seizure of the bearing portion of the sprocket 11 is eliminated.

(Effects of the Invention) As described above, according to the lubricating structure for a transfer of the present invention, the lubricating oil scattered in the gear case is collected by the oil gutter and is formed by the seal bearing and the partition plate on the end side of the sprocket. Since the lubricating oil is stored in the oil sump and the lubricating oil in the oil sump is supplied to the bearing portion of the sprocket, the effect of sufficiently supplying the lubricating oil and eliminating the occurrence of seizure or the like can be obtained.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a sectional view showing an embodiment of a transfer lubricating structure according to the present invention, and FIG. 2 is a sectional view showing a conventional transfer lubricating structure. 3: Transmission cover 5: Main shaft 11: Sprocket 18: Recessed step 19: Needle bearing 20: Through hole 21: Partition plate 22: Oil sump 23: Through hole 24: Oil gutter

Claims (1)

[Claims] 1. A seal bearing provided on an end face side of a sprocket rotatably mounted on a main shaft via a needle bearing, an oil reservoir formed by a partition plate and a sprocket end face, and oil is supplied to a needle bearing. A transfer lubrication structure comprising an oil hole on an end face of a sprocket and an oil gutter for collecting and supplying lubricating oil to the oil reservoir.