AU733358B2 - Bearing protection shield - Google Patents

Description

P/00/011 Regulation 3.2

AUSTRALIA

PATENTS ACT 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT

ORIGINAL

r TO BE COMPLETED BY APPLICANT :Name of Applicant: PETER GEORGE WHYTE Actual Inventor(s): Peter George Whyte Address for Service: CALLINAN LAWRIE, 278 High Street, Kew, 3101, Victoria, Australia Invention Title: "BEARING PROTECTION SHIELD" The following statement is a full description of this invention, including the best method of performing it known to me:- 26/8/97LP9376.CS,1 The present invention relates, in general terms, to a means for protecting a bearing or the like means, as for example a bush, which is mounted on any given shaft for rotation therewith. More particularly, but not exclusively, the present invention relates to a means which can be mounted on the shaft, in close proximity to a bearing or the like means, whereby to prevent ingress into the vicinity of the bearing and the associated shaft of unwanted material such as water, dust and other potentially damaging matter. The utilisation of the means in accordance with the present invention serves to increase the expected operating life of the bearing assembly, associated shaft, etc.

S10 Throughout the ensuing description and claims, for ease of explanation or eeee convenience of definition, the means in accordance with the invention will be

I

referred to as "a bearing shield or sealing means".

Again for ease of explanation, throughout the ensuing description reference will be made to a particularly preferred embodiment of the present invention, intended for use in or in conjunction with a bearing roller assembly of the type employed on, for example, trucks intended to transport concrete and the like cementitious material to any given site, wherein a plurality of roller assemblies are employed as carriers for an agitator means (rotatable barrel or the like) intended to house the cementitious material during transport. It must be realised, however, that the arrangement in accordance with the present invention is under no circumstances to be considered to be limited to use only in such a context. Indeed, a bearing shield in accordance with the present invention lends itself readily to usage in any context wherein a bearing or the like means, as for example a bush, is employed in conjunction with a rotating shaft whereby to retain such shaft in its correct or optimum operating position.

By way of further example only the bearing shield in accordance with the present invention could be employed on or in relation to transmission shafts for any type of vehicle, or indeed in any context wherein the ingress of unwanted material, be it in the form of liquid, solid and/or abrasive material, could be expected to have a deleterious effect. The shield or sealing means in 26/8/97LPWHYTE.SPE -3accordance with the present invention may, therefore, be used with industrial transmission shafts, wheels for vehicles, roller assemblies for tracked vehicles, indeed in any context wherein a rotating shaft, spindle or the like means is employed. A further example is with a roller conveyor assembly.

In any situation context wherein a rotating shaft is employed, there always exists the possibility of ingress into the system assembly of unwanted, and potentially damaging, material. This is perhaps nowhere more so the case than with carrier roller assemblies of the type employed on cement trucks in order to keep the drum containing the cement rotating, thereby improving the mix and, perhaps more importantly, ensuring that the mix does not set during transport. Cement is, or can be, an extremely abrasive substance. It has also been found to extremely pervasive or invasive. If such a substance finds its way into the roller assembly in general, it can with time give rise to significant damage thereto, in turn giving rise to the need for regular maintenance, repair and/or replacement. Apart from the actual cost of such maintenance, repair and/or replacement, the very need therefor means that the relevant vehicle has to be regularly off the road, and hence out of service. This gives rise to significant "down" time, and hence loss of income for the vehicle owner operator.

In like manner, the ingress of material such as water, dust, abrasives, etc. into any region wherein a shaft, spindle or the like is functioning to impart movement has the potential for damage, to the shaft or spindle, to a bearing means associated therewith, to the overall assembly.

The present invention seeks to overcome the aforementioned problem by providing a means which, in use, functions to minimise, if not remove altogether, the likelihood of ingress of such unwanted material into any system or assembly wherein a shaft or spindle is employed to impart rotation.

In accordance with a first aspect of the present invention there is provided an improved bearing shield or sealing means for preventing unwanted ingress of potentially damaging material into a rotatable assembly, said shield or sealing means including: an aperture adapted, in use, to allow for location of said shield or sealing means on or in conjunction with a rotatable shaft, spindle or the like means of said 08/03/01gc9376.spe,3 -4rotatable assembly; a planar portion extending radially outwardly from said aperture and substantially normally thereto; and a peripheral skirt extending radially outwardly from said planar portion and at an angle thereto, wherein said planar portion includes an annular projection depending substantially normally therefrom and extending across at least a portion of the radial dimension thereof, said annular projection being adapted to assist in locating said shield or sealing means relative to said shaft, spindle or the like means and maintaining its position thereon, wherein said planar portion provides a seating for a fixing means.for securing said shield or sealing means relative to said shaft, spindle or the like, the arrangement being such that said shield or sealing means, in operation, does not separate from said shaft, spindle or the like means.

In accordance with a further aspect of the present invention there is provided a bearing/roller assembly including: a roller body having an aperture therein and disposed substantially centrally thereof; a shaft, spindle or the like means adapted to extend through said aperture; bearing means mounted internally of said aperture and seated on at least one shoulder provided internally thereof; and a shield or sealing iii: means of the type referred to in the preceding paragraph.

In order that the invention may be more clearly understood and put into practical effect reference will now be made to especially preferred embodiments of a bearing shield in accordance with the present invention. The ensuing description is given by way of non-limitative example only and is with reference to the S accompanying drawings, wherein: FIG 1. is a side perspective view of a preferred embodiment of a bearing shield in accordance with the present invention; :O:h FIG 2. is a side view of one end of a roller assembly showing the bearing shield in place thereon; FIG 3.is an exploded view of the assembly of FIG 2.; FIG 4.is a view similar to FIG 2. of a further embodiment of a bearing shield in accordance with the present invention, as installed in a roller bearing assembly; FIG 5. is a view of an alternative embodiment of a bearing shield in accordance with the invention; 08/03/0 lgc9376.spe,4 4a FIG 6. is a view, similar to FIG of an alternative means for holding a bearing shield in place; and FIG 7. is a view of a grub screw used in the embodiment of FIG 6.

In FIG 1. there is illustrated an especially preferred embodiment of a bearing shield or sealing means, generally designated 1, in accordance with the present invention. The shield 1 is substantially circular in shape, having an aperture/orifice 2 located centrally thereof, thereby to allow said shield 1 to be appropriately disposed *a 08/03/01gc9376.spe,4 on a shaft 10 (see FIGS 3. and The shield 1 preferably includes a flat, planar portion 3 extending radially outwardly from the aperture 2, such flat portion 3 being adapted, in use, to provide a seating for a fixing means of any given type, as for example a hexagonal nut and cooperating spacer or washer, thereby to releasably fix the shield 1 in a predetermined, desired position on said shaft 10. In an alternative arrangement, as shown in FIG the bearing shield 1 may be suitably fixed on the shaft relative to the roller assembly using a threaded (internal) member of any given shape which can be appropriately located on the shaft 10 and fixed in position by means of one or more grub screws or the like 30. In the especially preferred embodiment illustrated the grub-screw or the like 30 will be in the form of a substantially cylindrical member, once again have an aperture/orifice located centrally thereof the cylindrical or annular member having four slots 33 disposed around the circumference thereof at 900 intervals. A preferably threaded bore extends through the annular member, such bore 35 being adapted to receive, and releasably retain, a means (not shown) which is operable to affix the grub-screw in place on the shaft 10. It should be realised however, that the actual means of a S fixing the bearing shield in place is not of the essence of the invention, and could be S• varied as desired dependent upon usage.

In the especially preferred embodiment of FIG 1. the shield 1 has a further skirt portion 4, extending radially outwardly from the end of said flat portion 3 and S descending downwardly at an angle therefrom. The end result is that, as illustrated in FIG the shield 1 when viewed in side elevation takes the form of a truncated, hollow cone or pyramid. This conical shape is in itself responsible for certain practical advantages in terms of improved sealing, as explained hereinafter in more detail.

:The shield 1 may be constructed of any suitable material, be it metal, plastics or a combination thereof. Preferably the shield 1 will be of a unitary construction.

In an alternative embodiment, as illustrated for example in FIG the shield 1 can have an upwardly extending annular extension 5 associated therewith. The provision of such extension 5 will facilitate mounting of a shield 1 in accordance with 2 /00,gc9376.spe.5 5a the present invention on a given shaft 10. This could again be achieved with or by the use of grub screws or the like.

The arrangement illustrated in FIGS 2. and 3. involves a bearing shield 1 in accordance with the present invention in conjunction with a roller of any given type, and more particularly a carrier roller assembly of the type used with r *4 20/12/00,gc9376.spe,5 concrete trucks and the like equipment.

The roller 20 itself involves a substantially cylindrical or annular body member 21 having an aperture 22 disposed substantially centrally thereof and extending thereacross, such aperture 22 being intended to house or contain a shaft or spindle 10, associated bearing means 12 and the like as described hereinafter. The shaft or spindle, generally designated 10, has a threaded portion 11 (externally threaded) towards the end thereof which is adapted to receive, and releasably retain, a suitable bearing means 12 (of any given or known type). The roller body member 21 includes internal shoulder 23 intended to provide a seating for such bearing 12. The conveyor body 21 preferably also includes a further internal shoulder 24 adapted, in use, to co-operate with a .i bearing shield 1 in accordance with the present invention. In the preferred embodiment illustrated that shoulder 24 includes a circumferential groove adapted to receive and releasably retain an additional sealing means, as for example an O-ring type seal 13. It should be realised, however, that such an additional sealing means is not essential to the practice of the invention, with the bearing shield 1 in accordance with the present invention in essence providing adequate sealing for the overall assembly. It should furthermore be realised that the further shoulder 24 need not be required. Indeed in an 0 alternative embodiment, not shown, the bearing shield 1 in accordance with the present invention will sit "flush" with the outermost surface of the roller assembly housing, which may be substantially flat with or without a groove or the like associated to receive and releasably retain an O-ring type seal, for example.

As shown the arrangement is that the bearing 12 is appropriately disposed on the shaft or spindle 10, with or without the interposition of an Oring type seal 13. The bearing shield 1 is then located on the shaft 10 and suitable means, as for example a hexagonal nut 15 and associated spacer or washer 14, are then disposed on the end of the shaft, thereby to lock the assembly together and bring the bearing shield 1 into the position shown in Fig.

2618/97LPWHYTE.SPE 2. When in such a position, the bearing shield 1 acts to prevent ingress of unwanted material to the interior of the roller and the associated bearing. Once again the fixing means could be of any known type, however, as for example an internally threaded annular member adapted to be disposed on the shaft, moved to the desired position on that shaft and then locked in position on said shaft by means of one or more grub screws or the like, adapted to extend through one or more apertures, preferably threaded, extending radially of said annular member whereby to come into contact with the surface of the shaft.

The advantages associated with this the arrangement in accordance with S10 the present invention, in terms of increased longevity of an overall bearing o.oo assembly, have been found to be significant. With cement trucks and the like i equipment, for example, it has been found that the abrasive nature of the i: cement or other cementetious material, when coupled with its pervasive nature, gives rise to significant damage to the carrier rollers, thereby necessitating regular replacement thereof. The need for such regular replacement not only gives rise to additional costs in terms of replacement parts, but even more importantly is responsible for significant "down time", in that the truck or the like must be withdrawn from service whilst such roller assemblies are being maintained repaired replaced.

Turning now to Fig. 5 of the drawings, there is illustrated therein an oooo alternative arrangement or further variation of a bearing shield in accordance with the present invention. Such an arrangement includes a central aperture or orifice a planar portion 3' extending radially outwardly therefrom and a skirt portion 4' extending at an angle from the planar portion In an especially preferred embodiment the skirt portion 4' extends at an angle of the order of 750 to the planar portion It should be understood, however, that the angle of inclination of the skirt portion 4' to the planar portion 3' is not of the essence of the invention. Indeed, such angle could vary dependent upon intended usage. The arrangement as illustrated includes a circumferential cavity 6, said cavity 6 serving to retain grease or the like lubricant, whereby to 26/8/97LPWHYTE.SPE lubricate the O-ring type seal.

The embodiment illustrated in Fig. 5 may be constructed from a metal or plastics material, or indeed a combination thereof. The skirt portion 4' also includes means 5 adapted, in use, to co-operate with a sealing means of any known type, as for example an O-ring type seal. As illustrated, the means may take the form of a circumferential groove.

The principle of operation of the bearing shield 1 in accordance with the present invention is that, when in place on or in relation to a bearing assembly, as illustrated for example in Fig. 2 of the drawings, the shield itself provides 10 sealing pressure against either the O-ring (if one is employed) or the synthetic face of the bearing housing. Such prevents ingress of unwanted or potentially *i damaging material into the bearing itself (and associated shaft).

The substantially convex shape of the skirt portion of the bearing shield 1 Shas the further advantage of allowing flow of lubrication. In a practical sense an appropriate lubricant can be constantly circulated within the bearing, thereby improving the life-span or operating longevity thereof.

The bearing shield 1 in accordance with the present invention has also been found to be able to compensate for any radial movement on the shaft.

Such is in marked contrast to the prior art arrangements, which couldn't cope .20 at all with such radial movement. In that regard it should be understood that, dependent upon loading (the contents of the agitator barrel of a concrete truck, for example), both the shaft itself and the overall housing therefor can, with time, exhibit eccentricities, which can result in the shaft being other than concentrically mounted within the overall assembly. Such other than concentric mounting, with the prior art arrangements, has been found to give rise to problems with ensuring adequate sealing. In practice with conventional seals, eccentricity or lack of concentricity in the shaft can give rise to intermittent lifting and separating, as though flexing, of a seal from the housing during rotation of the shaft, in turn allowing for ingress into the assembly of moisture, dust and other unwanted and potentially destructive matter. The substantially 26/8/97LPWHYTE.SPE convex shape of the skirt portion of the bearing shield in accordance with the present invention has been found to compensate for any flexing of the overall shield which might arise due to any eccentricity in the associated shaft. The end result is that the present applicant's arrangement is substantially proof against lifting and separation of the type experienced by the prior art arrangements, thereby at all times ensuring sealing.

It should be understood that the bearing shield in accordance with the present invention, in contrast to prior art arrangements, is not rotating on its associated shaft. That fact alone gives rise to improved operating life.

It should further be understood that the aforegoing description refers merely to preferred embodiments of the present invention and that variations and modifications will be possible thereto without departing from the spirit and scope of the invention, the ambit of which is to be determined from the following claims.

15 26/8/97LPWHYTE.SPE

Claims (11)

1. An improved bearing shield or sealing means for preventing unwanted ingress of potentially damaging material into a rotatable assembly, said shield or sealing means including: an aperture adapted, in use, to allow for location of said shield or sealing means on or in conjunction with a rotatable shaft, spindle or the like means of said rotatable assembly; a planar portion extending radially outwardly from said aperture and substantially normally thereto; and a peripheral skirt extending radially outwardly from said planar portion and at an angle thereto, wherein said planar portion includes an annular projection depending substantially normally therefrom and extending across at least a portion of the radial dimension thereof, said annular projection being adapted to assist in locating said shield or sealing means relative to said shaft, spindle or the like means and maintaining its position thereon, wherein said planar portion provides a seating for a fixing means for securing said shield or sealing means relative to said shaft, spindle or the like, the arrangement being such that said shield or sealing means, in operation, does not S separate from said shaft, spindle or the like means.

2. The shield or sealing means as claimed in Claim 1, wherein said fixing means is a threaded member, adapted to be located on said shaft, spindle or the like and fixed relative thereto by one or more grub screws.

3. The shield or sealing means as claimed in Claim 1 or Claim 2 which, when viewed in side elevation, has the form shape of a hollow truncated cone.

4. The shield or sealing means as claimed in any one of the preceding Claims, formed principally from a plastics material.

5. The shield or sealing means as claimed in any one of Claims 1 to 3, 25 formed principally from a metal. coco

6. The shield or sealing means as claimed in Claim 5, wherein said metal is stainless steel.

7. The shield or sealing means as claimed in any one of Claims 1 to 3, formed from a laminate of plastics material and a metal. 08/03/0 lgc9376.spe -11

8. The shield or sealing means as claimed in any one of the preceding Claims wherein said skirt, extending circumferentially around said shield or sealing means, includes at least one cavity for receiving a suitable lubricant.

9. A bearing/roller assembly including: a roller body having an aperture therein and disposed substantially centrally thereof; a shaft, spindle or the like means adapted to extend through said aperture; bearing means mounted internally of said aperture and seated on at least one shoulder provided internally thereof; and a shield or sealing means as claimed in any one of the preceding Claims.

A bearing shield or sealing means, substantially as described herein with reference to the accompanying drawings.

11. A bearing/roller assembly, substantially as described herein with reference to the accompanying drawings. .15 DATED this 8 th day of March, 2001. PETER GEORGE WHYTE By his Patent Attorneys: CALLINAN LAWRIE o9 *o 08/03/0 lgc9376.spe,I I ^^S t