JPH0231634Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a packing that seals a gap where two members move relative to each other in the axial direction. More specifically, the present invention relates to a gasket with reduced resistance when sliding relative to each other.

As a prior art related to the present invention, there is a packing shown in FIG. 1. Figure 1 shows a packing of a rubber product with a U-shaped cross section, with inner and outer circumferential surfaces 52 and 53 in the axial direction.
A large number of grooves 55 are provided in the groove. Furthermore, an annular pressure-receiving groove 54 that receives pressure is provided on the axial pressure-receiving surface 56, forming main lips 51 on both sides. The purpose of this gasket is to retain oil and fat in the groove 55 to reduce sliding resistance. However, when pressure is applied to the pressure receiving surface 56, especially the pressure receiving groove 54 and the gasket slides relative to the pressure receiving surface 56, especially the pressure receiving groove 54, the vicinity of the pressure receiving groove 54 repeats the transformation. Therefore, since the sliding surface is close to the pressure receiving groove 54,
Directly affected by this action, the grooves provided on the sliding surface are deformed, and eventually the oil and fat held in the grooves 55 are discharged. Furthermore, since the sliding surface generates frictional heat due to sliding, the viscosity of the oil and fat held in the grooves 55 of the sliding surface is reduced. This is groove 55
This means promoting the discharge of fats and oils retained in the water.

In addition, when the sliding surface is free of oil and fat, the protrusions between the grooves deform and come into contact with the sliding mating surface, increasing frictional resistance. Therefore, the frictional resistance of the sliding surface increases, and eventually the sliding surface wears out and the sealing quality deteriorates. Furthermore, since the seal seals by pressure against the sliding mating member, the power required to slide the mating member becomes large, resulting in loss of energy. Furthermore, when used for low pressure applications, the relative sliding member moves intermittently due to sliding resistance with the packing, which poses a problem in terms of use.

The present invention was developed in view of the above-mentioned problems, and the technical problem is to obtain a packing for low pressure use, which has low sliding resistance and has excellent sealing properties. It is in.

In order to solve the above problems, the present invention includes the following configuration.

That is, it has a substantially cylindrical shape and is molded with a fitting part and a rubber-like elastic material attached to one of two members that are assembled concentrically with each other and move relative to each other in the axial direction. It has a seal lip extending in a substantially cylindrical shape from the inner end of the holding part extending inward in the direction, and having a pressure receiving surface at its end, the seal lip having a conical first circumferential surface and a second conical circumferential surface.
a seal portion formed on the pressure-receiving surface side by a circumferential surface of the other member of the two relatively movable members; and a support portion formed with a support peripheral surface having a slightly larger diameter, and a plurality of oil sump recesses arranged in double rows on the peripheral surface of the support portion that slides on the other member. Equipped with a configuration.

It is preferable that the oil sump recesses arranged in the support part have a circular, square, or elliptical shape when viewed from the center line side.

Hereinafter, one embodiment of the present invention will be described in detail based on the drawings. FIG. 2 is a sectional view of the packing of the present invention. The packing forms an annular body 7 made of a rubber-like elastic material, has a fitting part 11 on the outer circumferential side, has an annular recess 3 on the pressure receiving side 2, and has a seal lip 4 between the annular recess 3 and the shaft 1. A dust lip 10 is formed axially opposite to the seal lip 4. The other member 1 of this seal lip 4
A seal part 5 projecting in an angular cross-section in the inner diameter direction and a support part 14 projecting with a rounded cross-sectional tip are provided in parallel at the contact part with the seal part 5 on the free end side. The seal portion 5 has a first circumferential surface 17 and a second circumferential surface 20 that are inclined with respect to an axis that intersects the opposite pressure-receiving side and the pressure-receiving side at a corner surface 21.
Further, a large number of oil sump recesses 18 are formed along the circumferential direction on the rounded and protruding support peripheral surface 9 that joins the other member 1 of the support portion 14 . The oil sump recess 18 is formed in various shapes such as a rectangular shape and an elliptical shape in addition to a circular shape.

Further, a reinforcing ring 6 made of metal and having an L-shaped cross section and having a radial portion 8 and an axial portion 16 is integrally fixed with the axial portion 16 disposed in the fitting portion 11 of the annular body 7. At the same time, the radial portion 8 of the reinforcing ring 6
is embedded in the holding portion 19 of the annular body 7 to support the bases of the seal lip 4 and dust lip 10.

The fitting portion 11 and the holding portion 19 are connected to the inner circumferential surface 15 on the one member 12 side and the supporting surface 2 of the supporting member 13.
2 to hold the packing.

The present invention configured as described above has the following effects. The seal lip 4 of the seal extends into a cylindrical shape and has a seal portion 5 with a rectangular cross section on its free end side, so that even if the pressure of the fluid to be sealed is low, the seal portion 5 follows the other member 1. Demonstrates sealing performance. On the other hand, if the support part 14 is not provided, when the seal part 5 is strongly pressed against the other member 1 due to the pressure of the fluid to be sealed, or it will slide against the other member 1 with friction. When joined, the tip side of the seal portion 5 is subjected to elastic deformation that increases the contact area. but,
In the present invention, the support part 14 aligned with the seal part 5 prevents the joint area of the seal part 5 from expanding, so that the seal part 5 maintains an optimal contact state. However, due to the seal portion 5 exhibiting a sealing effect, the fluid to be sealed is transferred to the support portion 14.
If oil is prevented from flowing out to the side, oil will no longer be present on the sliding support peripheral surface 9 of the support part 14, and the oil will slide with the other member 1 with friction, resulting in rapid wear. However, an oil sump recess 18 is provided in the sliding support peripheral surface 9 of the support part 14 of the present invention.
Since the oil is retained, an oil film is formed on the support peripheral surface 9 of the support part 14 as it slides, and friction and wear of the support part 14 can be prevented.
The support portion 14 has the effect of always holding the seal portion 5 so that it exhibits a sealing effect.

Therefore, the packing of the present invention has a seal lip 4 extending in a cylindrical shape and has a seal portion 5 on the free end thereof, so that it exhibits a sealing effect even in low pressure applications. In addition, the seal portion 5 is supported by the support portion 14 so as to always maintain an optimal sealing state, thereby effectively exerting a sealing force. Since the oil contained in the oil sump recess 18 forms an oil film on the sliding surface of the support part 14, the support part 14 can maintain the seal part 5 in an optimal sealing state without being worn out. Can be done.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a conventional packing, and FIG. 2 is a sectional view of a packing of the present invention. DESCRIPTION OF SYMBOLS 1... Other member, 2... Pressure-receiving side surface, 3... Annular recess, 4... Seal lip, 5... Seal portion, 6
... Reinforcement ring, 7 ... Annular body, 8 ... Radial direction part, 9
...Support peripheral surface, 10...Dust strip, 11...
Fitting portion, 12...one member, 13...supporting member,
14...Supporting part, 15...Inner circumferential surface, 16...Axis direction part, 17...First circumferential surface, 18...Oil sump recess, 19...Holding part, 20...Second circumferential surface , 21
... corner surface, 22 ... support surface, 51 ... main lip, 52 ... inner peripheral surface, 53 ... outer peripheral surface, 54 ...
Pressure receiving groove, 55...Groove, 56...Pressure receiving surface.

Claims (1)

[Scope of utility model registration request] A fitting part 11 is formed with a rubber-like elastic material and is attached to one member 12 of two members that are approximately cylindrical and are assembled concentrically with each other and move relative to each other in the axial direction. A seal lip 4 extends in a substantially cylindrical shape from the inner end of the holding portion 19 extending radially inward, and has the pressure receiving surface 2 at its end.
and the sealing lip 4 has a conical first shape.
The seal portion 5 has a corner surface 21 that slides on the circumferential surface of the other member 1 of the two relatively movable members formed on the pressure receiving surface 2 side by the circumferential surface 17 and the second circumferential surface 20.
and a support portion 1 having a substantially mountain-shaped cross-sectional shape and having a support circumferential surface 9 having a slightly larger diameter than the corner surface 21.
4, and is provided with a plurality of oil sump recesses 18 arranged in double rows on the peripheral surface of the support portion 14 that slides on the other member 1.