DE2331412A1 - Seal for high speed roller bearings - maintains supply of lubricant by fan to seal lip to reduce wear - Google Patents

Abstract

The seal is of the conventional U section form pressed onto the shaft with a garter spring. Immediately in front of the sealing lip a special disc is fitted which has a number of cut-outs in its periphery and the tongues which are thus formed are twisted at an angle to produce a small multi-bladed fan. When the shaft rotates oil mist is pumped over the seal ensuring adequate lubrication of the rubbing surfaces between the seal lip and the shaft. The disc may be made of metal or plastic and also may be arranged to firt under the lip of the seal.

Description

PATENT Attorney DR. HELGA WEISSENFELD 6940 Weinheim / Bergjtr.

η · ι / -Μ. -ι Höhnerweg 2

Chemist _{TeU> fon} ^ ₂₀₁ . ₈₀ ^ _{94 + 8618}

Telex 04 65 531

June 19, 1973 Dr. W / Sch ON 65I

Applicant: Carl Freudenberg, Weinheim

Sealing arrangement for two machine parts rotating relative to one another

The invention relates to a Abdichtanordnunp for two relative Machine parts rotating in relation to each other, which function perfectly even under inadequate lubrication conditions and thus Avoids leakage.

It is known to seal rotating shafts with the help of shaft seals. These are mainly made of elastomeric plastic manufactured shaft seals are subject to depending on

409884/0037

Operating conditions a high level of wear. With high-speed machines and especially with insufficient lubrication conditions When the sealing rings run dry, there is increased friction between the sealing lip and the rotating shaft on.

This friction can cause burns or increased wear on the sealing lip of the shaft seal lead, creating a leak.

For the proper functioning of the sealing arrangement it is absolutely necessary that the shaft sealing ring is always is bathed in lubricant.

Small amounts of oil are often sufficient to maintain the lubricant film, using spray disks can be brought up to the rotating shaft as an oil mist. An exemplary embodiment of a splash disk is in U.S. Patent No. 3,275,333 and U.S. Patent No. 3,479,728, with the splash disc at respective Flattening conditions can also be pulled onto the shaft as a separate part from the sealing ring. Despite the Installation of such splash disks and thus improved Oil distribution still occurs with many machine designs high wear on shaft seals. For example, a tapered roller bearing instead of a ball bearing has been used to support a shaft been that despite the oil splash disc, there was a lack of lubricant occurs. This lack of lubricant leads to the machine part heating up and even burning Shaft sealing lips. The conventional injection disks can therefore only be used to a limited extent and with tapered roller bearings mostly not sufficient. This is due to the fact that with tapered roller bearings Waves, the lubricant that penetrates the bearing is easily drained away and turns out to be oil ring settles. This oil ring usually lifts from the

-3-A09884 / 0037

233H12

rotating shaft and rotates with almost half the shaft speed between the shaft and the housing bore. the Formation of the oil ring is promoted by the fact that the lubricant in the tapered roller bearing in the radial direction is distracted. In the case of tapered roller bearings, it is known that the rollers run at an angle to the shaft to be supported. Even In the case of rotating housings, an oil ring that rotates with the housing speed easily forms, which does not rest on the shaft.

In all these cases as well as with machines, e.g. with gearboxes, where the oil level is lower than the lower edge of the shaft sealing ring is with increased wear of the sealing parts and the risk of leakage to be expected.

The invention is now based on the object of providing a satisfactory solution even under increased stress and under inadequate lubrication conditions To create a functioning sealing arrangement, in particular the dreaded oil ring does not occur or in time gets destroyed. This object is achieved in that a combination of a shaft sealing ring known per se is proposed with a suitably constructed conveyor disk adapted to this. This causes the conveyor disc transports the oil in the axial direction and the uniform wetting of the rotating or sealing Parts.

A sealing arrangement is proposed which is characterized is by a known shaft seal and a conveyor disk upstream of this, on their Recesses inclined like a fan wheel, blade-shaped angled tongues are arranged. The conveyor disc works

-H-

409884/0037

-f-

233U12

in the manner of an Axial-Putnpe, whereby the conveying effect extends in the direction of the sealing lip.

The sealing arrangement is in the same way both for rotating shafts and for a stationary shaft by itself suitable for these rotating machine parts. In all cases a perfect lubricating effect is obtained and avoided thus safe overheating, wear and tear and leaks.

According to an expedient embodiment of the sealing arrangement, the conveyor disk is designed as an angular ring, its Legs point radially outwards, the part of the angular ring parallel to the axis being the running point for the shaft sealing ring. The conveyor disk is made of metal and / or plastic.

The sealing arrangement proposed according to the invention has proven itself where there is reduced lubrication or dry running arises from the fact that a circulating oil ring is formed, that lifts off the wave. The arrangement has also proven itself in all cases of oil mist lubrication and oil surge lubrication of the shaft seal. Such lubrication conditions occur, for example, when rotating shafts in tapered roller bearings are stored, the sealing lip being lubricated by the conveying effect of the tapered roller bearing target. There are comparable lubrication conditions for machines, e.g. for gearboxes, where the oil level is lower than the lower edge of the shaft dic, htring or in the case of rotating housings, which are connected to the housing speed forms a rotating oil ring that does not rest on the shaft.

In all of the above-mentioned cases, the sealing device proposed according to the invention ensures the proper functioning Run of the machine part.

-5-

409884 / 003-7

Figures 1 to 4 serve to explain the invention proposed sealing arrangement. Show it

Figure 1 shows a cross section through the seal consisting of shaft, conveyor disk and shaft seal

FIG. 2 shows a cross section through a comparable sealing arrangement with angled ring-shaped conveyor disc

FIG. 3 shows a plan view of the conveyor disk designed according to the invention

Figure M is a view of the conveyor disk and an enlarged Section of the blade-shaped angled tongue.

Between the shaft 1 and the machine part 5 there is the sealing arrangement according to the invention consisting of a conveyor disk 2, at the recesses of which are inclined, blade-shaped angled tongues 3 that are inclined like a fan wheel and which, according to the embodiment according to FIG . The conveyor disk 2 can, as shown in FIG. 2, be designed as an angular ring, with the legs pointing radially outward in the direction of the housing part 5. The parallel to the rotating shaft 1 arranged part 6 of the angle ring serves as a running point for the shaft sealing ring H and sits with a press fit on the shaft. Part 7 shows a press-in mandrel for the sealing arrangement only intended for assembly.

FIG. 3 shows a plan view of the blank for a conveyor disk. The conveyor disc is to be installed in such a way that

-6-

409884/0037

the angled segments 3 »their angle between ο and 9o, exert a pumping effect in the direction of the sealing ring for a given direction of rotation.

The amount of lubricating fluid delivered in the axial direction depends on the one hand on the speed of the shaft and on the other hand on the angle at which the segments are bent are. By an additional inclination of the segments in the axial direction, the lubricant is on the rotating shaft or brought up to the sealing lip of the shaft sealing ring. It is thus possible in a simple manner, by more or less large deflection of the segments, the lubrication conditions in each case to the prevailing operating conditions adapt.

The conveyor disks according to the invention are made of metal or plastic or a combination of metal and plastic.

-7-

4Q988A / 0037

Claims (3)

Patent claims: 1. J sealing arrangement for two relative rotating Machine parts, characterized by a shaft sealing ring known per se and an upstream one Conveyor disc with a fan wheel at the recesses inclined, shovel-shaped angled tongues are arranged. 2. Sealing arrangement according to claim 1, characterized in that the conveyor disc is designed as an angular ring, whose legs point radially outwards, the axis-parallel part of the Winfeel ring running point for the Shaft seal is. 3. Sealing arrangement according to claim 1-2, characterized in that the conveyor disc made of metal and / or Plastic is made. 409884/0037 Blank page