AU677369B2 - Improved training idler roller assembly - Google Patents

Description

Regulation 3.2

AUSTRALIA

PATENTS ACT 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT

ORIGINAL

e* o 0* Name of Applicant: THEODORE BEVIN JOHN MASTROSAVAS Actual Inventor: THEODORE BEVIN JOHN MASTROSAVAS eq Address for Service: R K MADDERN ASSOCIATES, 345 King William Street, Adelaide, South Australia, Australia S Invention title: IMPROVED TRAINING IDLER ROLLER ASSEMBLY Details of Associated Provisional Application No: PL 7113 dated 05/02/1993 The following statement is a full description of this invention, including the best method of performing it known to me.

1 I This invention relates to an improved training idler roller used on conveyor belt systems, and in particular relates to a training idler roller that provides responsive adjustment of a conveyor belt as the belt becomes misaligned.

Conventionally training idler rollers comprise a series of rollers which are mounted on a frame having a centre pivot.

At each side of the roller assembly there is provided an edge roller having a vertical axis of rotation. The roller is mounted on the end of a lever arm which is mounted on either side of the frame. When the belt moves far enough across the main rollers the edge of the belt rides against the edge roller and the resulting force causes the main roller assembly to pivot.

In this pivoted position the belt now travels across the rollers at an angle to the axis of rotation of each roller and consequently a component of this motion results in the belt sliding along the axis of the roller. The resultant drag created by this motion causes the belt to move with respect to the rollers so as to realign the conveyor belt.

Once realignment has occurred the idler roller will rotate o back to the normal running position.

S2 Numerous other proposals for correcting belt alignment have been proposed, but the above described prior art is by far the most populrr training idler roller.

However, it still has numerous disadvantages which result in increased maintenance of both the roller assembly and belt.

For example it is not uncommon for the pivot to seize due to infrequent operation, in which case the belt will ride up over the edge roller and remain in this position causing severe damage to the belt.

A further disadvantage with this type of training idler roller is that no correction of the conveyor belt occurs until it contacts the edge rollers. Therefore the belt needs to be well out of alignment before any correction occurs.

2 I '~U A still further problem is that this training idler roller can only operate effectively with the conveyor belt travelling in one direction. Therefore this type of training idler roller cannot be used on convevor belts which travel in both directions. In addition the size of these roller assemblies or the projections on either side can be a disadvantage, particularly when clearance from adjacent structures or equipment is required.

Therefore, it is an object of this invention to provide a trailing idler roller assembly which overcomes the abovementioned problems.

It is a still further object of this invention to provide a training idler roller assembly which provides subdtantially instantaneous correction of the belt as it becomes misaligned.

In its broadest form the invention comprises a training idler roller assembly for controlling the alignment of a conveyor belt along a conveyor line comprising, a frame for supporting a plurality of conveyor belt idler rollers, a pivot connection between said frame and conveyor line support which S. allows said frame to rotate with respect to both said support '..145 and conveyor belt, about a vertical axis, said idler rollers arranged such that at least two rollers are located either side of said pivot and have their axis of rotation spaced 0000 with respect to the vertical axis of said pivot such that the conveyor belt contacts these displaced rollers before passing over said pivot.

Each training idler roller assembly may comprise several separate idler rollers, but according to the invention, at least two of the idler rollers have an axis of rotation which is spaced from the centre pivot. Preferably, these two idler rollers are the outermost idler rolJler either side of the 3 I Ypivot, and in one aspect of the invention, there is provided a single roller either side of the pivot which has an axis of rotation spaced from the vertical axis of the central pivot.

In another aspect of this invention, there may be provided pairs of idler rollers having parallel and spaced axis of rotation, with a pair being located either side of the pivot with each roller's axis of rotation of each pair spaced either side of the vertical axis of the pivot. In this aspect of the invention, the idler roller assembly will control alignment of a conveyor belt travelling in either direction over the roller assembly.

The axis of rotation of the idler rollers may be inclined with respect to a horizontal plane so as to allow the roller assembly to be used with a trough shaped or V shaped conveyor belt. Alternatively, the idler rolleis mpy be arranged in a common horizontal plane for use with a flat conveyor belt.

oooo It has been found that training idler roller assemblies in accordance with the above description are extremely responsive to misalignment of the conveyor belt and provide a virtually instantaneous response which moves the conveyor belt back into realignment. It has been found that as the conveyor belt moves transversely with respect to the roller oooo assembly such that it goes into a misaligned position, a turning moment is created about the centre pivot of the trainer idler roller assembly which causes the assembly to rotate about the centre pivot. Each of the rollers which have axis of rotation spaced away from the centre pivot contact the conveyor belt before any of the other rollers.

Transverse movement of the belt with respect to the training idler roller assembly, coupled with forces caused by the mass of material on the conveyor belt, will cause the assembly to rotate about the pivot. Rotation of the training idler roller assembly then imparts a force to the belt which acts to centralise the belt with respect to the trainer idler rolling assembly.

4 A preferred embodiment of the invention will now be described, but it should be realised that the invention is not to be confined or restricted to the precise details of this embodiment. This embodiment is illustrated in the accompanying representations in which: FIG. 1 shows a perspective view of a training idler roller assembly, and FIG. 2 show, a partly sectioned side view of a training idler roller assembly.

In this embodiment, the training idler roller assembly 10 is designed for use with a flat conveyor belt. The assembly comprises a central idler roller 11 and a pair of idler rollers 12 and 13 either side of the central idler roller 11.

S" All of the idler rollers 11 to 13 have their axes of rotation in a common plane, and hence the assembly 10 is for use with a flat conveyor belt.

Each of the idler rollers 11 to 13 are attached for rotation to a frame 14 which in turn is secured via a pivot 15 to a conveyor line support or sub-frame 16. In this embodiment, a sub-frame 16 is used to secure the assembly to a frame or upright which forms the base for the conveyor line.

Alternatively the pivot 15 may connect the frame 14 direct to conveyor line support which comprises the base.

90ee eoee 9 The sub-frame 16 is provided with stops 17 which are arranged to abut against the frame 14 as it rotates so as to limit its a&.ount of rotation.

As can be seen in FIG. 1, each pair of idler rollers 12 and 13 are arranged such that they have spaced and parallel axis of rotation. A pair is located on either side of the central idler roller 11, and are positioned such that each roller's axis of rotation of each pair 12 and 13 is spaced either side of the vertical axis of pivot 15. In this arrangement, depending on the direction of travel of the conveyor belt, 5 -1 clL~--Il one roller of each of the pairs 12 and 13 will impact against the conveyor belt before the conveyor belt runs over the central idler roller 11.

When the conveyor belt becomes decentralised with respect to the training idler roller assembly 10, the conveyor belt will contact the leading idler rollers of each of the pairs 12 and 13 before contacting the central idler roller 11. The transverse movement of the belt into a misaligned position coupled with the forces caused by the mass of the )nveyor belt and material carried by the belt will cause the training idler roller assembly 10 to rotate about the pivot 15 which will then cause the belt to move over the roller assembly such that a restoring force is applied to the belt causing it to again centralise. As soon as the belt centralises, the 0:0 roller assembly 10 pivots such that the rollers return to a position where they are transversed along the longitudinal axis of the belt.

The use of pairs of idler rollers 12 and 13 assist in increasing the speed with which the belt centralises after becoming misaligned.

It has been found that any small transverse movement of the belt with respect to the roller assembly 10 will generate a respo-Se which causes an immediate rotation of the roller assembly 10 about the pivot 15 thereby causing a likewise immediate correction of the belt position. The degree of eoee belt movement will control the amount of rotation of the roller assembly 10, and hence if there is a large transverse deviation of the belt, then a large corrective force will be applied to the belt.

One important advantage of the invention is that it provides constant movement of the roller assembly, thereby preventing the pivot 15 from seizing through inactivity, which is particularly important in a corrosive environment. In the case of priox art idler roller assemblies that use end rollers to cause rotation of the assembly, this corrective 6 rotation does not normally occur until the belt actually contacts the end rollers. Hence, the belt can run in a misaligned position without necessarily causing the assembly to rotate. This has been found to cause the pivot to seize through non use hich obviously can be avoided with the present inventio..

Although this embodiment shows a roller assembly 10 for use with a flat belt, it should be clear to the person skilled in the art that the pairs of idler rollers 12 and 13 may be inclined with respect to the horizontal so as to be used with a trough shaped coriveyor belt. In addition, the roller assembly 10 can be designed for use with a V shaped conveyor belt.

person skilled in the art will readily recognise that the invention provides significant advantages in respect of the :i presently available prior art. In particular it provides constant adjustment of conveyor belt tracking, and therefore reduces belt wear and maintenance problems associated with known idler roller assemblies.

oe0 oooo **oo 0 7 _i

Claims (9)

1. A training idler roller assembly for controlling the alignment of a conveyor belt along a conveyor line comprising, a frame for supporting at least two conveyor belt idler rollers, a pivot connection between said frame and conveyor line support which allows said frame to rotate with respect to both said support and conveyor belt, about a vertical axis, said idler rollers arranged such that rollers are located either side of the centre- line of said conveyor belt and have their axis of rotation spaced with respect to the vertical axis of said pivot such that the conveyor belt contacts these displaced rollers before passing over said pivot, said assembly not reliant upon any physical barrier to the edge of said conveyor belt for alignment of said conveyor belt.

2. A training idler roller assembly according to claim 1 comprising at least one centrally located idler roller with its axis of rotation located over said pivot with rollers located either side of said centrally located idler roller.

3. A training idler roller assembly for controlling the alignment of a conveyor belt along a conveyor line comprising, a frame for supporting at least four conveyor belt idler rollers, a pivot connection between said frame and conveyor line support which allows said frame to rotate with respect to both said support and conveyor belt, about a vertical axis, said idler rollers arranged such that a pair of rollers are located either side of the centre-line of said conveyor belt and have their axis of rotation spaced with respect to the vertical axis of said pivot such that the conveyor belt contacts these displaced rollers before passing over said pivot, said assembly not reliant upon any physical barrier to the edge of said conveyor belt for alignment of said conveyor belt. I L,

4. A training idler roller assembly according to claim 3 comprising at least one centrally located idler roller with its axis of rotation located over said pivot with said pairs of idler rollers located either side.

5. A training idler roller assembly according to any one of claims 1 to 4 wherein said idler rollers are all in the same horizontal plane for use with a flat conveyor belt.

6. A training idler roller assembly according to any one of claims 1 to 4 wherein said idler rollers are arranged for use with a V-shaped conveyor belt.

7. A training idler roller assembly according to any one of claims 1 to 4 wherein said idler rollers are arranged for use with a trough shaped conveyor belt.

8. A training idler roller assembly for use with a trough shaped conveyor belt :15 according to either claim 2 or claim 4 wherein said centrally located idler roller has an horizontal axis of rotation with the idler rollers either side of said central idler roller having inclined axes of rotation. 0*

9. A training idler roller assembly substantially as hereinbefore described with 20 reference to the accompanying drawings. Dated this 8th day of February 1997. 1 THEODORE BEVIN JOHN MASTROSAVAS By his Patent Attorneys MADDERNS C ABSTRACT This invention relates to a training idler roller assembly for controlling the alignment of a conveyor belt al.ng a conveyor line and in particular to a roller assembly which is able to move a conveyor belt from a misaligned position to a centralised position. The roller assembly comprises a frame (14) for supporting a plurality of conveyor belt idler rollers (11-13), a pivot (15) connected between said frame (14) and a conveyor line support which allows the frame (14) to rotate with respect to both the support and a O conveyor belt, about a vertical axis, the idler rollers (11- 13) being arranged such that at least two of the rollers are located either side of the pivot (15) and have their axis of rotation spaced with respect to the vertical axis of the pivot (15) such that the conveyor belt contacts these displaced rollers before passing over the pivot When the conveyor belt becomes misaligned, and decentralised over Sego the idler roller assembly it is caused to rotate about the pivot (15) which in turn causes a force to be applied to the belt such that it moves to a central position which in turn restores the roller assembly (10) such that the axis of rotation of each of the idler rollers (11-13) is transverse to the longitudinal axis of the conveyor belt. e001 S e S S.o. I