AU2001100481B4 - Auger - Google Patents

Description

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION INNOVATION PATENT Applicant: BRIAN INVESTMENTS PTY LTD Invention Title:

"AUGER"

The following statement is a full description of this invention, including the best method of performing it known to me/us: 2 Improved Auger The present invention relates to an auger for removing particulate material from a storage bin or hopper.

Particulate material and in particular grain is often stored in storage bins. These storage bins are often located with their bottom near or below ground level. In order to remove the grain from the storage bin the grain is directed, via a hopper, into an auger which moves the grain in a relatively upward direction for further transport, etc.

Existing augers have a bearing at the base of the auger screw. Often storage bins will collect water in the wet season and any grain left will swell and jam the auger.

Alternatively the bearing may rust and seize. Removing the auger screw for maintenance and/or removal of water is a difficult and time consuming task usually conducted by attaching rope or cable to the end of the auger screw and pulling it out of the tunnel leading from the bottom of the storage bin and housing the auger. This can often result in damage to the auger.

An object of the present invention is provide an auger that is less susceptible to these problems.

According to a first aspect of the present invention there is provided an auger for removing particulate material from a storage bin or hopper, said auger comprising at least: an outer tube having an inlet at a first end for receiving particulate material and an outlet at a second end of the outer tube; a centre tube inside the outer tube and rotatable about a longitudinal axis of the centre tube, the centre tube having a helical flight along the length of the centre tube for moving particulate material from the inlet to the outlet as the centre tube rotates, the centre tube mounted to the outer tube by a first bearing and a second bearing, spaced from the first bearing; a drive means for rotating the centre tube; and 3 a lifting means for raising the outer tube relative to the storage bin.

According to a third aspect of the present invention there is provided an auger for removing particulate material from a storage bin or hopper, said auger comprising at least: an outer tube having an inlet at a first end for receiving particulate material and an outlet at a second end of the outer tube; a centre tube inside the outer tube and rotatable about a longitudinal axis of the centre tube, the centre tube having a helical flight along the length of the centre tube for moving particulate material from the inlet to the outlet as the centre tube rotates, the centre tube mounted to the outer tube by a first bearing and a second bearing, the first bearing being located inside the centre tube a suitable distance towards the second end from the first end of the outer tube, the second bearing located adjacent the second end of the outer tube; a drive means for rotating the centre tube; and 4 a lifting means for raising the outer tube relative to the storage bin.

Preferably the centre tube includes a sealing means located inside the centre tube a predetermined distance from the first end for creating an air pocket in a lower portion of the centre tube. Preferably the first bearing is located in the lower portion of the centre tube.

Preferably the outer tube is located inside a tunnel, in use, the tunnel leading from the bottom of the storage bin to a location relatively higher than the bottom of the storage bin in a substantially straight line.

Preferably the inlet of the outer tube is provided with a hopper.

Preferably the outer tube is suspended in the tunnel. Preferably the lifting means is arranged to move the outer tube up the tunnel. Preferably a centre tube is provided with double helical flights along a portion of it's length.

Preferably the diameter of the path rotation of a tip of the flight is slightly less than the inner diameter of the outer tube. Preferably the diameter of the centre tube is at least half of the diameter of the path of rotation of the tip of the flight.

Preferably the first bearing is coupled to an end of a shaft that extends from the first end of the outer tube inside the centre tube. Preferably the shaft is in the form of a stub axle.

In one embodiment the first bearing is coupled to: a cavity tube inside the centre tube, the cavity being removably fixed to the centre tube; and the stub axle inside the cavity tube, the stub axle being fixed to the outer tube.

In another embodiment the first bearing is coupled to a bearing cap expandingly coupled to the inside of the centre tube. The bearing is located inside the cap and the stub axle inside the bearing.

Preferably a seal is provided between the centre tube and the shaft. More preferably a seal is provided between the cavity and the stub axle.

Preferably the lifting means is in the form of a rack and pinion arrangement, wherein the rack is fixed relative to the tunnel and the pinion is fixed relative to the outer tube, whereby rotation of the pinion causes the outer tube to move in relation to the tunnel.

Preferably the pinion is rotated by a crank handle. Alternatively the pinion is rotated by a motor. Alternatively the lifting means is in the form of a screwjack.

In order to provide a better understanding, a preferred embodiment of the present invention will now be described in detail, by way of example only, in relation to the accompanying drawings, in which: Figure 1 is a cross-sectional side elevation of a prior art auger; Figure 2 is a cross-sectional side elevation of a lower portion of an auger in accordance with the present invention; Figure 3 is a cross-sectional side view of an upper portion of the auger of Figure 2; Figure 4 is a cross-sectional side view of a seal between a centre tube and a cavity tube of the auger of Figure 2; Figure 5 is an enlarged cross-sectional view of a lower portion of the auger of Figure 2; and Figure 6 is a cross-sectional side view of an alternative embodiment of an auger in accordance with the present invention.

In Figure 1, prior art auger 10 comprises a centre shaft 12 having a helical flight 13 extending along it's length. The shaft 12 and flight form a screw that is situated within a tube 14. The tube 14 is situated in a tunnel 15 that extends from a hopper 11 in an upward direction. The shaft 12 is mounted to the tube 14 by a bearing 16 at the base of the shaft 12. Rotation of the shaft 12 causes particulate material to be moved in an upward direction by the flight 13.

In Figure 2, a preferred embodiment of an auger 20 in accordance with the present 6 invention includes a centre tube 22 having a helical flight 24 extending along it's length.

The centre tube 22 and flight 24 form a screw that is located within an outer tube 28.

The outer tube 28 extends along the inside of a tunnel 15. The inside of the outer tube is connected to by a hopper 11 to a storage bin via an inlet 36.

A base plate 34 is located at the end of the outer tube 28. Extending from the base plate 34 inside the centre tube 22 is a shaft 32. At an end of the shaft opposite the base plate 34 is a bearing 30 that couples the shaft 32 to the centre tube 22.

At a lower portion of the length of the centre tube 22 a second flight 26 forms a double helix screw to assist in moving the grain toward an outlet 35. The diameter of the path of rotation of the tips of the flights 24 and 26 are slightly less than the inner diameter of the outer tube 28. The flights 24 and 26 when rotated pass close to, but do not contact the inside of the outer tube 28. The diameter of the centre tube 22 is about one half to two thirds of the diameter of the inside of the outer tube 28 to allow for the shaft 32 and bearing A carrier of the outer tube 28 suspends the outer tube 28 inside the tunnel by a slide rail 52. At a distal end of the tunnel 15 an end cap 51 is provided to prevent foreign material falling into the tunnel 15 and the outer tube 28. The outer tube 28 extends through an aperture 53 inthe end cap 51. The outlet 38 is provided at the higher end of the outer tube 28.

A rack 56 is fixed in relation to the tunnel 15. A pinion 54 operatively associated with the rack 56 is fixed in relation to the outer tube 28. In this case the pinion 54 is fixed in relation to the end cap which is fixed in relation to the outer tube 28 so that upon rotation of the pinion 54, the end cap 51 and thus the outer tube 28 and screw is moved in relation to the tunnel 15. A screw jack or other suitable lifting means may be provided as an alternative.

Referring to Figure 3, at the distal end of the centre tube 28 there is provided a projecting shaft 46 is coupled by a bearing 44 to an end plate 42 of the outer shaft 28.

7 The shaft 46 is operatively connected to a drive motor 50 by a gearbox 48.

Referring to Figure 5, it can be seen that the centre tube 22 includes a cavity tube extending along a part of the length of inside the centre tube 22. The cavity tube 60 is removably fixed inside the centre tube 22. At the bottom end of the centre tube 22 a seal 62 is provided between the centre tube 22 and the cavity tube 60 to prevent the ingress of foreign material.

The shaft 32 is in the form of a spigot shaft. The distal end of the shaft 32 is provided with the bearing 30, which contacts with a housing and seal at the distal end of the cavity tube 60. The distal end of the cavity tube includes a spigot 74 extending from the housing and a draw bolt 76 extending from the spigot 74. The centre tube includes a support block 72 for receiving the spigot 74 and bolt 76 in a hole 78.

In Figure 4, the seal 62 is shown in more detail. The seal 62 includes complimentary inclined interfering rings 64 and 66. A groove 68 is provided for receiving an o-ring to complete the seal 62.

Referring to Figure 6, an alternative embodiment of an auger according to the present invention is shown. Like features of the previous embodiment are the same in this embodiment, with reference numerals indicating the same features. In this embodiment the bearing 30 is coupled to the centre tube 22 by a bearing cap 100 and a coupling means 102. The bearing 30 is located inside the bearing cap 100 and affixed onto a projection 108 of the shaft 32. The coupling means 102 is in the form of a collar that lines the inside of the centre tube 22, the collar having an inclined surface against which is abutted a wedge member that is moved by the tightening of a bolt. Wedge member slides against an inner collar that is fixed to the bearing cap 100. With the winding of the bolt the wedge member moves along the inclined surface of the outer collar in a manner whereby the inner collar and outer collar are forced apart in an expanding manner the outer collar thereby pressing against the inside of the centre tube thus fixing the bearing cap 100 in position within the inside of the centre tube 22.

-8- The cap 100 has an end 104 that faces the second bearing 44. A sealing means 106, preferably in the form of a setting silicon rubber, is injected into the centre tube 22 and sits on the end 104 of the cap 100. Once set the sealing means 104 seals the centre tube airtight so that a pocket of air is created within a gap 112 between the shaft 32 and the centre tube 22. The air pocket resists the ingress of liquid, such as water, into the centre tube 22 to keep the bearing 30 and coupling means 102 dry.

Optionally a set of flights 110 maybe provided at the base of the centre tube 22 would in a helical manner opposite to the helical winding of the flight 24. Upon rotation of the centre tube 22 to cause material to move along the length of the centre tube 22, the flights 110 cause material to move in the opposite direction. Thus any material that attempts to pass through the gap 112 toward the bearing is forced back down the winding of the centre tube 22. The flighting 110 is generally fixed to the centre tube with a small clearance with the shaft 32. The flighting 110 may be removed so as to allow access to the coupling means 102 and servicing of the bearing.

The method of use and operation of the present invention will now be described in relation to Figures 2 to Particulate material, such as grain stored in a storage bin, enters hopper 11 which then passes through the inlet 36 into a lower end of the outer tube 28. When it is desired to remove the grain from the storage bin, the motor 50 is activated which in turn causes the centre tube 22 to rotate in a direction whereby the flight 24 (and flight 26) move the particulate material from the lower end of the outer tube 28 along the length of the outer tube 28 to the outlet 38. After the storage bin has been emptied and/or when it is desirable to conduct maintenance, the pinion 54 may either be rotated (by a hand crank or by a motor) which causes the outer tube to move in relation to the rack 54 and thus the tunnel thereby moving it at least partially out of the tunnel 15. The carrier of the outer tube 28 slides along the slide rail 52. The inside of the tunnel can be checked and/or de-watered and maintenance can be conducted on the screw and/or bearing The outer tube 28 is then lowered back into place ready for its next operation.

9 The skilled addressee will understand that the present invention has at least the following advantages: due to the increased diameter of the centre tube additional strength is provided and thus a longer length of screw can be provided and/or the screw can be rotated at a greater speed because less whipping occurs; grain or other material can be more easily removed from the lower end of the auger; de-watering of the inside of the tunnel can be more easily conducted; maintenance of the lower end of the auger and/or the flights can be more easily conducted; and the air pocket in the centre tube resists the ingress of water, thereby reducing the risk of corrosion of the first bearing and coupling means.

It will also be obvious to the skilled addressee that modifications and variations can be made to the present invention without departing from the basic inventive concept. Such modifications may include altering the diameter of the tubes and/or changing the means for driving the centre tube and/or pinion. Such modifications are intended to be within the scope of the present invention the nature of which is to be determined from the foregoing description and appended claims.

Claims (4)

1. An auger for removing particulate material from a storage bin or hopper, said auger comprising at least: an outer tube having an inlet at a first end for receiving particulate material and an outlet at a second end of the outer tube; a centre tube inside the outer tube and rotatable about a longitudinal axis of the centre tube, the centre tube having a helical flight along the length of the centre tube for moving particulate material from the inlet to the outlet as the centre tube rotates, the centre tube mounted to the outer tube by a first bearing and a second bearing, spaced from the first bearing; a drive means for rotating the centre tube; and a lifting means for raising the outer tube relative to the storage bin.

2. An auger for removing particulate material from a storage bin or hopper, said auger comprising at least: an outer tube having an inlet at a first end for receiving particulate material and an outlet at a second end of the outer tube; a centre tube inside the outer tube and rotatable about a longitudinal axis of the centre tube, the centre tube having a helical flight along the length of the centre tube for moving particulate material from the inlet to the outlet as the centre tube rotates, the centre tube mounted to the outer tube by a first bearing and a second bearing, the first bearing being located inside the centre tube a suitable distance towards the second end from the first end of the outer tube, the second bearing located adjacent the second end of the outer tube; a drive means for rotating the centre tube; and a lifting means for raising the outer tube relative to the storage bin.

3. An auger according to any one of claims 1 to 2, wherein the centre tube includes a sealing means located inside the centre tube a predetermined distance from the first end for creating an air pocket in a lower portion of the centre tube. 11

4. An auger according to any one of claims 1 to 3, wherein the first bearing is coupled to an end of a shaft that extends from the first end of the outer tube inside the centre tube, the first bearing also coupled to a bearing cap expandingly coupled to the inside of the centre tube.