JPH0110964Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a flexible seal used in a left tillage processing device of a center drive type cultivator.

In order to till the uncultivated ground that remains directly below the transmission case of a center-drive tiller, a rotary tube with an axis inclined with respect to the axis of the tilling shaft is installed on the outer periphery of the tilling shaft at the innermost part near the transmission case. A residual tillage processing device is known in which a tillage claw is installed in the tillage claw. This type of residual tillage processing device is provided with a flexible seal at the outer end of the tilted rotary cylinder to seal the gap between the rotary cylinder and the tilling shaft, and this flexible seal is made of rubber or the like. They are weak in strength and easily damaged by plants, pebbles, dirt, etc. that get caught in the sealing part, often causing accidents such as oil leaks.

As an improvement to this, as shown in Japanese Utility Model Publication No. 51-4163, a disc-shaped cover is provided on the core of the flexible seal to seal the outer circumference of the tilted rotating shaft (cylindrical shaft). However, since it is necessary to provide a large diameter hole in the core of this cover into which the tilling shaft is loosely fitted, there is a problem in that it is difficult to sufficiently protect the flexible seal.

This invention provides a seal structure with a more effective protection measure, and is characterized by a cylindrical lip that protrudes outward on the outer periphery of the annular flexible seal body. In addition to being integrally provided across the lip, a protective disk is provided on the tilling shaft side that is inscribed in this lip over the entire circumference. The embodiments shown in the drawings will be described below.

Fig. 1 is a cross-sectional view of the main parts of a rotary tiller having a flexible seal according to the present invention. A rotary pipe 4 forming the outer periphery of the tilling shaft is spline-fitted to the right and left outer sides of the tilling shaft 2. Tilling claws 5, 5, . , are fixed by bolts 7. Attachment seats 9 are fixedly provided on both left and right sides of the transmission case 1, and an inner flange 10a of a cylindrical fixed shaft 10 is fixed to the mounting seats 9 with bolts 11. The cylindrical portion 10b of the fixed shaft 10 is formed to have a circular cross section, and its axis A is inclined with respect to the axis B of the tilling shaft 2 by an angle α (α is preferably about 4 to 5 degrees) so that the outside is lower. ing. In addition, the fixed shaft 10
An intersection point P between the axial center A of the plowing shaft 2 and the axial center B of the tilling shaft 2 is formed so as to be located outside the outer end of the cylindrical portion 10b of the fixed shaft 10.

An inclined rotary cylinder 13 is fitted onto the outer periphery of the cylindrical portion 10b of the fixed shaft 10 via bearings 12, 12, and tilling claws 14 for residual tillage treatment are planted on the outer periphery. Since the inclined rotary cylinder 13 rotates around the axis A of the fixed shaft 10, the tilling claws 1 for residual tillage processing
4 plows directly below the transmission case 1 below the tilling shaft 2 and passes outside the transmission case 1 above. A drive gear 15 is spline-fitted to the tilling shaft 2 between the fixed shaft 10 and the rotary pipe 4, and an internal gear 16 is formed on the inner circumference of the inclined rotary cylinder 13.
is meshed with this drive gear 15. Rotational power is transmitted from a power agricultural machine (not shown) to the tilling shaft 2 via a chain case 17 and a sprocket wheel 18 in the transmission case 1, and this rotational power is transmitted to the drive gear 15 and the internal gear 16. It is transmitted to the inclined rotating cylinder 13 through the meshing relationship between the two. In the figure, 1
Numerals 9 and 20 are snap rings, and 21 is a seal ring that seals the joint between the fixed shaft and the tilted rotary cylinder.

As shown in FIG.
is provided, and a stepped small diameter portion 15c is provided on the outer periphery. Spline 15b of drive gear 15
A gasket 15d that is in contact with the outer peripheral surface of the tilling shaft 2 is disposed on the inner side. Further, the inner periphery of the side end opening of the inclined rotary cylinder 13 is enlarged in diameter, and a flexible seal 22 is fitted between the enlarged diameter part 13a and the small diameter part 15c. In the illustrated example, the flexible seal 22 is disposed near the outer periphery of the intersection P of the axes. Flange portion 2 of a core bar 23 with an L-shaped cross section provided on the outer periphery of the flexible seal 22
3a is in close contact with the end face of the inclined rotary cylinder 13,
A cylindrical lip 24 protrudes further outward from this portion over the entire circumference. The lip 24 is provided integrally with the flexible seal 22, and is made of a material such as rubber or synthetic resin like the flexible seal.
It is formed into a tapered cylindrical shape with an outer diameter smaller than an inner diameter. The flexible seal and lip may be made integrally of different materials. Further, on the inner surface of the lip 24, a lid-shaped protective disk 25 is disposed whose outer peripheral surface 25a is a spherical surface centered at the intersection P of the axes A and B. The protective disk 25 has a spline hole 2 provided in the core.
5b is spline-fitted to the tilling shaft 2, and its outer peripheral surface 25a is always kept inscribed in the lip 24 of the flexible seal. In this case, the lip 24 is formed in a tapered shape, and the outer circumferential surface 25a of the protective disk 25 is biased to expand it, so that the protective disk 25 and the outer cylinder The adhesion with the parts is extremely good. protection disk 25
A stepped notch 25c is formed on the inner surface of the rotary pipe 4, and the boss 15a of the drive gear 15 is partially fitted into this portion, and the seal 26 of the rotary pipe 4 is formed on the outer surface 25d of the boss 15a of the drive gear 15. The inner end surface fitted with is in contact with the inner end surface. The drive gear 15 connects the spline cut-up end 2a of the tilling shaft 2 and the protection disc 2.
5. An annular seal protection cover 27 fixed to the inclined rotary cylinder 13 by bolts 28 is provided on the outside of the flexible seal portion with a space between it and the lip 24.

In the rotary cultivator of the illustrated example configured as above, the flexible seal 22 is provided near the axial center intersection P of the inclined rotary cylinder 13 and the tilling shaft 2.
The amount of deflection of the flexible seal 22 is kept small,
That's what makes it so durable. Further, since the main body of the flexible seal 22 is protected by a lip 24 for preventing intrusion of foreign matter and a protective disk 25 inscribed therein, damage caused by foreign matter such as pebbles, plants, etc. is prevented. In this case, since the outer circumferential surface of the protective disk 25 is formed as a spherical surface, good contact between the lip 24 and the protective disk 25 is always maintained over the entire circumference of the inclined rotary cylinder 13. In the illustrated series, a seal protection cover 27 is additionally provided on the outside of the lip 24, so that the protection for the flexible seal body is more complete.

As is clear from the above description, the seal structure according to this invention protrudes outward over the entire circumference of the flexible seal body that seals the opening formed at the outer end of the tilted rotary cylinder. By providing an integral lip and providing a cover-shaped protective disk with a spherical outer surface that is inscribed in this lip over the entire circumference, it is possible to effectively protect the flexible seal body. Despite the structure, it has become possible to effectively prevent foreign matter such as pebbles and soil from entering the side portions of the flexible seal, greatly improving the durability of the flexible seal.

[Brief explanation of the drawing]

Figure 1 is a sectional view of the main parts of the cultivator to which the present invention has been applied;
Figure 2 is an enlarged view of the main parts. 1... Transmission case, 2... Tilling shaft, 4... Rotary pipe, 5... Tilling claw, 9... Mounting seat, 10
... Fixed shaft, 13 ... Inclined rotary tube, 14 ... Tilling claw for residual tillage processing, 15 ... Drive gear, 16 ... Internal gear, 22 ... Flexible seal, 23 ... Core metal, 2
4...Rip, 25...Protection disk, 25a...
...Outer surface.

Claims (1)

[Scope of utility model registration request] This is a seal structure used to seal the open end of the tilted rotating shaft where the tilling claws for residual tillage processing of a center drive tiller are installed, and the seal structure has an annular flexible seal body with an outer circumferential portion facing outward. A flexible seal with a lip that is integrally provided with a protruding cylindrical lip over the entire circumference is provided at the open end of the tilted rotary shaft, and a tilling shaft provided inside the tilted rotary shaft is provided with a flexible seal with a lip that is integrally provided over the entire circumference. A seal structure for a flexible seal with a lip, characterized in that a protective disk is provided inscribed in the lip of the flexible seal.