AU2011201080A1

AU2011201080A1 - A Sealing Ring

Info

Publication number: AU2011201080A1
Application number: AU2011201080A
Authority: AU
Inventors: Gary Payne
Original assignee: CBC AUSTRALIA Pty Ltd
Current assignee: CBC AUSTRALIA Pty Ltd
Priority date: 2010-03-10
Filing date: 2011-03-10
Publication date: 2011-09-29
Anticipated expiration: 2031-03-10
Also published as: AU2011201080B2

Abstract

Abstract This invention concerns a single piece sealing ring for use with slow moving bearings, such as those used in conveyors. The sealing ring comprises an annular sleeve having inner surface that, in use, seals to the shaft, and an outer surface that, in use, seals to the rotary labyrinth seal. The outer surface of the sealing ring is shaped along its length with at least two spaced apart radial channels that, in use, interdigitate with the labyrinth seal. The external end of the annular sleeve (the end outside the assembly) is shaped with an integral radially extending flange having a distal end which extends back towards the internal end of the sleeve. The internal end of the annular sleeve (the end inside the assembly) includes an integral radial channel with a distal flange. In use grease moves through the serpentine path without hydraulic effect and exits through the outer lip seal. 146 144 142

Description

AUSTRALIA F B RICE & CO Patent and Trade Mark Attorneys Patents Act 1990 CBC AUSTRALIA PTY LTD COMPLETE SPECIFICATION Invention Title: A Sealing Ring The following statement is a full description of this invention including the best method of performing it known to us:- 2 Title A Sealing Ring Technical Field 5 This invention concerns a sealing ring for use with slow moving bearings, such as those used in conveyors. Background Art 10 A bearing housing generally forms an annular opening within which a drive shaft is mounted for rotation. An assembly of rolling bearings are generally captured between the exterior of the shaft and the annular opening of the housing to enable rotation of the shaft. A sealing cover is bolted to the bearing housing. A rotary labyrinth seal is bolted 15 to the front of the sealing cover to retain lubricant, keep the lubricant from becoming polluted and protect the bearings. A serpentine seal between the rotary labyrinth seal and the shaft is completed by a sealing ring captured between them. Disclosure of the Invention 20 The invention is a single piece sealing ring for use with a bearing assembly including a rotary labyrinth seal and a shaft. The sealing ring comprises an annular sleeve having an inner surface that, in use, seals to the shaft, and an outer surface that, in use, seals to the rotary labyrinth seal. 25 The outer surface of the sealing ring is shaped along its length with at least two spaced apart radial channels that define one side of a serpentine path, the other side of which is defined by the labyrinth seal. The external end of the annular sleeve (the end outside the assembly) is shaped with an integral radially extending flange having a distal end which extends back 30 towards the internal end of the sleeve such that, in use, it forms a lip seal against the outside of the labyrinth seal through which grease can exit the serpentine path. The internal end of the annular sleeve (the end inside the assembly) includes an integral radial groove defining a distal flange that, in use, seals against the interior of the labyrinth seal but allows grease to enter the serpentine path. In use grease moves 35 through the serpentine path without hydraulic effect and exits through the outer lip seal.

3 The inner surface of the sealing ring is shaped with a series of integrated 'O'-rings that are sized to seal against the shaft and provide firm location on the shaft, but also allow the shaft to spin, in use, in the event of a blockage. 5 The integral radial channel at the internal end of the annular sleeve may comprise a 'V' shaped trench, where the distal flange of the 'V' is free to flex. The sealing ring may be machined from a block of diamine cured polyurethane. 10 One or more grooves may extend longitudinally along the outer surface of the sealing ring. These groove may extend in depth to the bottom of the spaced apart radial channels. These grooves facilitate grease transfer through the serpentine path, and ameliorate the hydraulic effect. 15 In a further aspect the invention is a sealing ring for use in a bearing assembly and having a cross section substantially as shown in the accompanying drawings. Brief Description of the Drawings 20 An example of the invention will now be described with reference to the accompanying drawings, in which: Fig. I is a pictorial view of a sealing ring. Fig. 2 is a sectional view through the sealing ring of Fig. I in situ with a mating labyrinth seal cover and part of a bearing housing. 25 Fig. 3 is a cross-sectional view of another sealing ring. Fig. 4 is a cross-sectional view of another sealing ring. Fig. 5 is a cross-sectional view of another sealing ring. Fig. 6 is a cross-sectional view of another sealing ring. Fig. 7 is a cross-sectional view of another sealing ring. 30 Fig. 8 is a cross-sectional view of another sealing ring. Fig. 9 is a cross-sectional view of another sealing ring. Fig. 10 is a cross-sectional view of another sealing ring. Fig. 11 is a cross-sectional view of another sealing ring. Fig. 12 is a cross-sectional view of another sealing ring. 35 Fig. 13 is a cross-sectional view of another sealing ring.

4 Best Modes of the Invention The sealing ring 100 is intended for use with a bearing assembly 200 including a rotary labyrinth seal cover 220 and a shaft 240. The bolts that hold the labyrinth seal cover 5 220 to the bearing assembly 200 are not shown but a pair of empty bolt holes 202 and 204 are shown in Fig. 2. In particular the sealing ring 100 comprises a sleeve 110 penetrated by a longitudinally extending bore 120. The sealing ring 100 has an inner surface 130 facing the bore 120. 10 In use, the inner surface 130 contacts the shaft 240. The sealing ring also has a an outer surface 140 that opposes the labyrinth seal 220. The outer surface of the sealing ring 140 is shaped along its length with two spaced apart radial channels 142 and 144 with a ridge 146 in between them. There are 15 additional ridges 147 and 148 on out sides of channels 142 and 144. In use the channels 142 and 144, and ridges 146, 147 and 148 interdigitate with corresponding formations 222, 224 and 226, on the labyrinth seal to form a labyrinth. The external end of the annular sleeve 150 is shaped with an integral radially extending 20 flange 152. The distal end 154 of flange 152 extends back towards the internal end 160 of the sleeve. In Fig. 2 where the flange 152 is shown in cross-section, it can be seen to be formed like an arm that has an elbow 156 at which it bends. Beyond elbow the distal end 154 of the flange is free to flex. 25 The internal end 160 of the annular sleeve 100 includes an integral radial channel 162 with a distal flange 164 that is free to flex. In this example the integral radial channel 162 has a 'V' shaped profile, and it is the distal flange of the 'V' 164 that is free to flex. The inner surface 130 has an integral interference 'O'-ring, that is a series of integral 30 'O'rings 132 separated by grooves 134 (for clarity only one pair is numbered), and it is these that seal against the shaft. Two grooves 170 extend longitudinally along the outer surface 140 of the sealing ring 100. These grooves extend through the ridges 146 and 148 to the depth of the bottom of 35 the spaced apart radial channels 142 and 144. These grooves facilitate grease transfer through the serpentine seal, and ameliorate the hydraulic effect.

5 The sealing ring is typically machined from a block of diamine cured polyurethane. The serpentine path created between the labyrinth seal 220 and the sealing ring 100 5 operates in conventional fashion, using centrifugal forces to seal when the shaft is rotating. This operation prevents ingress of dust and other contaminants to the bearings. At the same time it promotes egress of grease and contaminants from the bearings in the direction of arrows 180, 182 and 184. Furthermore, the lip seal defined at the tip 158 of distal end 154 of flange 152 that runs along the surface 228 of the 10 moving labyrinth seal 220 operates as a conventional lip seal that is capable of purging grease. In Figs. 3 to 13 the cross-sections of another eleven different sealing rings are shown. All these sealing rings are variations of the invention. 15 Although the invention has been described with reference to particular examples, it should be appreciated that it could be exemplified with numerous minor variations and modifications, and in combination with other features not mentioned above.

Claims

1. A sealing ring for use with a bearing assembly including a rotary labyrinth seal and a shaft, wherein the sealing ring comprises: 5 an annular sleeve, wherein the outer surface of the sleeve is shaped: along its length with spaced apart radial channels; at the external end with an integral radially extending flange having a distal end which extends back towards the internal end of the sleeve; and, at the internal end with an integral radial groove defining a distal flange. 10

2. A sealing ring according to claim 1, wherein the inner surface of the sleeve is shaped with a series of integrated 'O'-rings that, in use, seal against the shaft.

3. A sealing ring according to claim I or 2, wherein the integral radial channel at 15 the internal end of the annular sleeve comprises a 'V' shaped trench, where the distal arm of the 'V' forms the flange.

4. A sealing ring according to claim 1, 2 or 3, wherein one or more grooves extend longitudinally along the outer surface of the sealing ring to a depth equal to the bottom 20 of the spaced apart radial channels.

5. A sealing ring for use in a bearing assembly and having a cross section substantially as shown in any one of Figs. 3 to 13 of the accompanying drawings. 25