Abstract:
Replaceable intake section ( 14 ) of grain auger ( 10 ) includes fixed metal elongate support ( 22 ) secured to tubular casing ( 11 ) and extending beneath flexible intake end flight portion ( 17 ) which is connected by a clutch to the main flight of auger ( 10 ). Pliable, soft, rubber, safety guard or collar ( 27 ) is part-circular in section and extends around flight portion ( 17 ). Longitudinal edges on guard ( 27 ) normally engage with edges ( 34 ) of support ( 22 ). If an obstruction, such as an operator&#39;s foot, engages the auger intake, free end portions of guard ( 27 ) can disengage from edges ( 34 ) of elongate support ( 22 ) to minimise jamming or injury. Collar ( 27 ) may be attached to adjustable slide ( 25 ) to vary the length of flighting ( 17 ) exposed and thereby alter the rate of feed.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     The present application is a National Stage Application claiming the priority of co-pending PCT Application No. PCT/AU2004/000589 filed May. 7,2004, which in turn, claims priority from Australian Application No. 2003902218, filed May. 9, 2003. Applicants claim the benefits of 35 U.S.C. §120 as to the PCT application and priority under 35 U.S.C. §119 as to the said Australian application, and the entire disclosures of both applications are incorporated herein by reference in their entireties. 
     FIELD OF THE INVENTION 
     This invention relates to new and useful improvements to augers, in particular an auger used for conveying grain and other particulate material. In one particular form the invention relates to an improved guard arrangement fitted to a material conveying auger at its intake or feed end and which is designed to reduce the risk of serious injury or damage to a person working in the near vicinity thereof. 
     BACKGROUND OF THE INVENTION 
     In my earlier filed Australian Patent No. 756760 entitled “Improvements in and relating to grain augers and the like”, there is disclosed a safety guard device for fitment at the intake end of the auger in the form of a soft pliable tubular extension sleeve arranged to encircle at least a portion of the intake flighting, the sleeve being attachable to the lower or intake end of the auger casing which surrounds the main drive shaft and its helical flighting. Although this arrangement is still considered quite satisfactory further developments have been made in order to simplify the construction of the safety guard in order to make it more economical to manufacture and more suited to the purpose for which it is designed. 
     It is an object of the present invention to provide an improved form of a safety guard arrangement for a material conveying auger which is simple in construction, economical in manufacture, can be readily fitted to an existing auger, and which, even further reduces the risk of serious injury or damage by engagement of a person&#39;s limb or a foreign object with the exposed intake portion of the auger intake flight. 
     Another object of the present invention is to provide an improved safety guard arrangement for an auger at its intake end and which is designed so that the extent of exposed portion of the intake flighting can be conveniently varied by an operator to in turn control the rate of intake of grain (or any other material) at the intake end. 
     It is a still further object of the present invention to provide an improved safety clutch mechanism for the intake end of an auger assembly which is housed wholly within the tubular shaft of an auger intake section and which enables the intake flighting, in the event of it being damaged to be readily replaced without disturbing the clutch mechanism. 
     SUMMARY OF THE INVENTION 
     In one aspect the present invention accordingly provides a safety guard arrangement for an auger of the type including an elongate tubular casing, an auger flight on a main auger shaft jouralled for rotation in said tubular casing, said flight having an intake end flight portion, characterised by: 
     fixed elongate support means secured to said tubular casing at one end thereof and arranged to extend longitudinally therefrom beneath said intake end flight portion of said auger flight, said support means including longitudinally extending engagement surfaces on opposed sides of said intake end flight portion, and 
     a pliable part circular protective collar secured to said elongate tubular casing and which extends circumferentially around said intake end flight portion, said part circular collar forming a co-axial extension of said elongate tubular casing at said one end thereof, wherein said collar has transversely spaced apart axially extending edges which engage and are supported by said longitudinally extending engagement surfaces. 
     It will be appreciated that the use of the pliable collar partly surrounding the intake flighting largely eliminates potential pinch points and thus greatly minimises the likelihood of a serious injury being suffered should a limb of an operator become caught in the intake end of the auger. 
     It is also an advantage of the present invention that in the event of an obstruction engaging within the intake end auger portion, portions of the free ends of the safety collar are able to detach from their respective engagement surfaces with the result that the opening around the intake flighting is increased and there is less chance of jamming occurring. Furthermore with one or both of the collar ends disengaged, it is easier for the obstruction to be pulled out rather than being caught by the intake flighting and drawn in thereby. In a situation where the obstruction is a hand or foot of an operator, it is essential that it can be withdrawn from the flighting without serious injury or damage. 
     Preferably, the casing includes a part circular slide slidably and co-axially mounted on said one end of said elongate tubular casing with said part circular pliable collar being secured to the outer end of said part circular slide, said slide being slidable co-axially with respect to the casing with said axially extending edges on the collar being supported by said engagement surfaces for slidable movement therealong, whereby the extent of exposed intake helical flighting on the intake end flight portion can be selectively varied. 
     By having the safety collar attached to a slide on the casing, it is possible to minimise amount of exposed intake flighting when the auger is not in use. This is also advantageous at start up of the auger, particularly when certain types of material are being conveyed and there is a danger of overloading the auger at start up. After start up, the rate of flow of material can be varied by retracting the slide and thereby exposing more intake flighting. 
     Preferably, each of the axially extending edges on the part circular collar includes a rebate portion which defines an outwardly opening recess which abuts a respective engagement surface. 
     Optionally, each of the edges on the part circular collar includes spaced apart approximately parallel inner and outer lips which define a groove or slot for receiving and locating over a respective said engagement surface. 
     Preferably, the part circular collar is formed from a soft pliable plastics or rubber material. 
     Preferably, the auger flight includes a main flight section and an intake flight section separate from said main flight section, said intake flight section including a central tubular support sleeve and intake helical flighting secured to said tubular sleeve, an intake end auger shaft portion extending from and rotatable with the main auger shaft, said tubular support sleeve being rotatably mounted co-axially on said intake end auger shaft portion, and drive coupling means operably coupling the intake flighting tubular support sleeve and said intake end auger shaft portion, arranged so that when said intake helical flighting is subject to an overload condition, said drive coupling means automatically disengages drive to the tubular support sleeve. 
     Clearly, this improves safety and reduces injury in the event of an hand or foot of an operator being accidentally caught in the intake end of the auger as the intake helical flighting will cease being driven when the drive coupling means automatically disengages drive to the tubular support sleeve. 
     Preferably, the intake helical flighting is formed of resilient flexible wear resistant material. 
     Preferably, the intake helical flighting is substantially similar in diameter and configuration to the flighting on said main flight section and is aligned therewith. 
     Preferably, the auger shaft is supported at the intake end of the auger for rotation in a bearing support arrangement which is mounted at the outer end of said elongate support means. 
     Preferably, the bearing support arrangement includes a ring-like mounting bracket fixedly secured to the outer end of said support means, and an integrally formed bearing support member detachably fitted to said bracket centrally thereof, said bearing support member including an apertured portion for rotatably receiving an end of said auger shaft and a plurality of radially extending arms or legs which are spaced around the periphery of said apertured portion, each said arm or leg having its outer free end removably located in an opening in the wall of said ring-like bracket, said legs being resiliently deformable. 
     With this arrangement, in the event of a bearing support needing replacement, this can be done quite readily by deforming the radial legs so as to disengage their outer ends from their apertures in the mounting bracket, removing the bearing support member and thereafter refitting a new bearing support member. 
     Preferably, the support means includes a unitary metal plate which has an arcuate portion at its inner end and a pair of transversely spaced apart V-section bars extending longitudinally from said arcuate portion at its outer end, each said bar being to said mounting bracket said arcuate portion being releasably clamped to said main auger casing by means of a plurality of ring clamps. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       With the foregoing in view, and other advantages as will be come apparent to those skilled in the art to which this invention relates, a preferred embodiment of the invention is hereinafter described with reference to and as illustrated in the accompanying drawings wherein: 
         FIG. 1  is a fragmentary perspective view of a safety guard arrangement fitted to the intake end of a conventional auger, according to a preferred embodiment of the invention; 
         FIG. 2  is a view similar to  FIG. 1  showing the adjustable slide in a retracted position; 
         FIG. 3  is a fragmentary perspective view similar to  FIG. 2  and which shows a draw bar attachment pivotally connected to the underside of the auger and which can attach to a towing vehicle for transporting the auger; 
         FIG. 4  is an exploded perspective view of the assembly shown in  FIG. 1 ; and 
         FIG. 5  is a fragmentary perspective view of the clutch device mounted on the intake end auger shaft portion (with the intake flighting removed therefrom). 
     
    
    
     In the following description, like reference characters designate like or corresponding parts through out the several views of the drawings. 
     DESCRIPTION OF PREFERRED EMBODIMENT 
     Referring to the accompanying drawings, there is shown an auger assembly  10  which includes an elongated tubular auger casing  11  having a main drive shaft  12  journalled for rotation therein and around which is provided a main auger flight  13  having an intake end flight portion, this arrangement all being of conventional design. In this embodiment, a portion of the auger has been cut-off from its intake end so as to permit the fitment of a replacement intake section  14 . 
     The replacement auger intake section  14  includes an intake flighting section  15  which comprises a central tubular support sleeve  16  and flexible helical flighting  17  secured thereto and being similar in diameter and configuration to the flighting  13  of main auger flight section. The tubular support sleeve  16  has an inner square section metal tube through which extends an intake end auger shaft portion  19 ′ which, in this embodiment, is directly coupled to the main drive shaft  12  so as to rotate therewith and forms a co-axial extension thereof. The coupling of the intake end shaft portion  19  and the main drive shaft  12  can be effected in a number of different ways which will be well known to those skilled in the art. 
     The outer end of the intake shaft  19  is supported for rotation in a bearing support member  20  which itself is removably fitted to a circular bracket  21  which is fixed to the outer end of an elongate metal plate support  22  which in turn is secured at its inner end to the lower or bottom end of the main casing  11  and projects longitudinally therefrom. In this embodiment the metal support  22  is secured to the casing  11  by means of ring clamps  23  which engage around the outside of the casing  11  at spaced apart locations therealong. This is clearly shown in  FIG. 4  of the drawings. 
     In this embodiment, the metal outer casing  11  is provided with an adjustable slide  25  slidably mounted at the lower end thereof for axial movement with respect thereto between a fully extended position wherein a relatively small amount of intake helical flighting  17  is exposed (refer  FIG. 1 ) and a fully retracted position wherein substantially the whole of the intake helical flighting  15  is exposed. In this way the rate of flow of material being transported by the auger can be regulated by adjusting the position of the slide  25  so as to decrease or increase the volume of material being fed into the intake end. 
     Attached to the outer end of the slide  25  is a protective substantially part circular safety collar or skirt  27  formed of soft pliable rubber or rubber-like material, the inner side of the collar  27  being fastened, eg. by means of fasteners  28 , to the outer periphery of the slide  25 . The collar  27  has a part circular shape (when fitted) and defines a co-axial extension of the slide  25 . In this embodiment the collar or skirt  27  is formed from a flat blank of soft pliable rubber or rubber-like material—the stiffness of which can vary depending on the type of material being transported by the auger. As shown in  FIG. 4 , the axially extending edges  31 ,  32  of the part circular collar or skirt  27  are rebated on the outside face of the collar. The rebated ends  31 ,  32  resiliently engage against respective longitudinal edge portions  33 ,  34  of the elongate metal support  22 . This ensures that the collar or skirt  27  is retained in a part circular shape around the intake helical flighting  17  in close proximity thereto. The abutting engagement of the rebated ends  31 ,  32  with edge portions  33 ,  34  on the support  22  allows the collar  27  to slide along the elongate support  22  when the axial position of the slide  25  is adjusted. 
     In this embodiment the slide  25  is also part circular and is guided for axial sliding movement with respect to the casing  11  by means of elongate slots  38  formed in the wall of the metal slide  25  and guide pins or studs  39  fixed to and projecting from the outer surface of the main casing  11 . Desirably the slide  25  is also provided with a handle  40  which can be grasped by an operator in order to effect axial adjustment of the slide  25 . 
     It should be appreciated however that the protective collar or skirt  27  can be attached to the lower end of the main casing  11  in a situation where the slide  25  is not utilised. In this instance, the amount of exposed intake helical flighting  17  would not be able to be varied unless collars of different widths are used. 
     In this embodiment, the bearing support member  20  is moulded of plastics material and comprises a central bearing housing portion  42  and a plurality of radially outwardly directed legs  43 , each of which has its free end held captively engaged in an aperture  44  formed in the wall of the ring bracket  21 . The legs  43  are resiliently deformable and are designed, under force, to bend so that they can be detatched from the ring bracket  21 . This construction has two significant advantages. Firstly, in the event of a bearing support member  20  being damaged or worn, it can be readily replaced. Secondly, the deformability of the bearing support member  20  also assists in minimising the likelihood of an obstruction, eg. a boot or foot of an operator, being jammed in the intake flighting in a situation where such obstruction protrudes into and/or through the ring bracket. The bearing support is designed so that it will deform appreciably to allow the obstruction to be withdrawn or dislodge itself from its mounting bracket. 
     Referring now to  FIG. 5  of the drawings, a clutch device  47  is provided at the inner end of the intake end shaft portion  19  to drivingly couple the intake flighting tubular support sleeve  16  to the intake end auger shaft portion  19  and in turn the main drive shaft  12 . In this embodiment the clutch device  47  is a multi-stage assembly consisting of a plurality of driver and driven clutch plate elements  48 ,  49  respectively. The driven plate elements  49  are shaped correspondingly to the square section of the tubular sleeve  16  of the intake flight section  15  and hence rotate with the intake helical flighting  17 . 
     In the event of an overload situation, the driver and driven clutch elements will disengage and thereby disengage drive to the intake flight section  15  which can then freely rotate about the intake end shaft portion  19 . A heavy compression spring  50  is designed to urge the clutch elements  48 ,  49  into keying engagement with one another, with the spring  50  abutting against the outer one of the driver elements  48  at one end thereof, and at its other end against an end face of the bearing  52  which is mounted at the outer end of the intake end shaft portion  19 . It is advantageous that the clutch device  47  is completely housed interiorly of the intake flighting tubular support sleeve  16  and can therefore be sealed off. Furthermore, in the event of the intake flight section  15  having to be replaced, this can be done without disturbing the clutch device. The tubular sleeve  16 , when the bearing support is dismantled, can simply slide off the shaft  19  and a replacement intake flight section  15  fitted. 
     A brief consideration of the above described embodiment will indicate that the invention provides an extremely simple, economical safety feature for a material conveying auger which is effective to significantly reduce the risk of serious injury or damage by engagement of a person or object with the exposed portion of the intake auger flight. 
     Although a preferred embodiment the present invention has been described in the foregoing detailed description, it will be understood that the invention is not limited to the embodiment disclosed, but is capable of numerous rearrangements, modifications and substitutions without departing from the scope of the invention as set forth and defined by the following claims.