AU2005202398B2 - Conveyor Support - Google Patents

Description

P/00/011 28/5/91 Regulation 3.2 AUSTRALIA Patents Act 1990 ORIGINAL COMPLETE SPECIFICATION STANDARD PATENT Name of Applicant: Harry Anthony Thomas Jones Actual Inventor Harry Anthony Thomas Jones Address for service is: WRAY & ASSOCIATES Level 4, The Quadrant 1 William Street Perth, WA 6000 Attorney code: WR Invention Title: "Conveyor Support" The following statement is a full description of this invention, including the best method of performing it known to me: 1 -2 "Conveyor Support" Field of the Invention This invention relates to conveyors and has particular application to cable conveyors where the conveyor belt is supported along its length by at least one 5 cable and where each cable is received over a pair of end pulleys and a set of intermediate pulleys along the length of the conveyor. At least one of the pulleys is driven and the resultant movement of the at least one cable causes corresponding movement of the conveyor belt. The cable is intended to carry the conveyor belt and in this role is supported along its length by the pulleys. 10 Throughout the specification and claims, unless the context requires otherwise, the term "cable" will be taken as comprising cable, rope, or belt or like flexible elongate member which is utilised in a cable conveying system for driving and/or carrying the conveyor belt. Throughout the specification and claims, unless the context requires otherwise, 15 the term "cable conveyor" shall be taken as comprising a conveyor having two ends and at least one endless cable extending between the two ends, the at least one cable supported at each end by an end pulley, the at least one cable supported intermediate the ends by a set of intermediate pulleys and the at least one cable supporting an endless belt or like element. 20 Throughout the specification and claims, unless the context requires otherwise, the word "comprise" or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated integer or group of integers but not the exclusion of any other integer or group of integers. Background 25 It is a characteristic of cable conveyors that the weight of the upper run of the conveyor belt and its contents are supported by the pulleys. It is further characteristic of such systems that the wear which is experienced by the pulley - 3 can be quite excessive when the load being carried by the conveyor approaches the upper limits of its carrying capacity. This results in the carrying capacity of the conveying system being limited. This wear on the pulleys can be particularly high where the conveyor changes inclination such as at the upper ends of 5 inclines or declines where the conveyor changes direction. These changes in direction can occur because of undulations in the ground or the like or the requirements of the site. It is a further characteristic of such conveyor systems that they generate a large amount of noise which arises from the engagement of the cable with the 10 perimeter of each of the pulleys of the system. It is believed that most of the wear is exerted on the pulleys and the generated noise is as a result of the configuration of the cable which is used as the in the conveyor. The cable takes a conventional form in that it is formed with a number of groups of fibres or wires which define separate cords which are twisted 15 together. As a result on the cable engaging the perimeter of the pulley there is a limited point-like loading between each cord and the perimeter of the pulley. Furthermore because of twisted configuration of the cords, as the cable is caused to move over the surface of the pulley the points of contact between the cable and pulley move laterally over the pulley surface which generates a 20 considerable amount of frictional engagement and wear. In addition the movement of the cable over the pulley and the twisted nature of the cable causes the pulley to be sequentially engaged by the lower surfaces of the cords which form the lower surface of the cable which in turn causes a degree of upward and downward relative moment of the cable on the pulley which in turn generates a 25 vibration which is transmitted to the pulleys and conveyor. This vibration generates a noise, the magnitude of which is directly proportional to the number of pulleys contained within the conveyor, the loading exerted upon the conveyor, the length of the conveyor and the speed of the conveyor. The combination of the wear on the pulleys and the noise generated by the 30 engagement of the pulleys and cable creates the limiting factor in regard to the - 4 carrying capacity of a conveying system rather than the structural characteristics of the conveyor. Disclosure of the Invention Accordingly the invention resides in a cable conveyor pulley arrangement 5 comprising a plurality of pulleys supported from a base such that their axes of rotation are parallel and their rotation paths are substantially coplanar, an endless flexible belt member supported over the pulley to extend between the endmost pulleys to be caused to rotate with rotation of the pulleys, the outer surface of the belt being adapted to receive and support a cable. 10 According to a preferred feature of the invention the outer face of the belt is configured to provide a groove which will receive the cable. According to a preferred feature of the invention the pulley arrangement comprises a pair of pulleys. According to a preferred feature of the invention the end-most pulleys are 15 supported from the base whereby the weight of the conveying element borne by the end-most pulleys will increase the tension of the belt. According to a preferred feature of the invention the end-most pulleys are each rotatably supported from an arm member, each arm member being pivotally supported from the base and wherein the length of the belt is such as to cause the spacing 20 between the end-most pulleys to be less than their maximum possible spacing, the arm members being supported from the base such that the axes of each arm member between their pivotal support on the base and the rotation axis of the respective pulley are upwardly divergent. Accordingly the invention also resides in a cable conveyor having two ends and 25 an endless cable extending between the to ends, the cable supported at each end by an end pulley, the cable supported intermediate the ends by a set of intermediate pulleys at least some of the pulleys being incorporated into a - 5 conveyor pulley arrangement of the form as claimed at any one of the preceding claims. According to a preferred feature of the invention the at least some of the pulleys comprise the intermediate pulleys. According to a preferred feature of the 5 invention the at least some of the pulleys comprise the end pulleys. The invention will be more fully understood in the light of the following description of one specific embodiment. Brief Description of the Drawings The description is made with reference to the accompanying drawings of which: 10 Figure 1 is a schematic side elevation of a pulley arrangement according to the embodiment showing the pulleys engaged by a belt; Figure 2 is a schematic side elevation of a pulley arrangement according to the embodiment showing the pulleys in the absence of a belt; Figure 3 is a plan view of the pulley arrangement according to the embodiment; 15 Figure 4 is a partial sectional elevation of a pulley supporting a belt according to the embodiment; Figure 5 is a cross sectional elevation of a belt according to the embodiment supporting a cable; Figure 6 is an illustration of a possible arrangement in the application of two sets 20 of pulleys in accordance with the embodiment. Detailed Description of Specific Embodiments The embodiment is directed to a cable support arrangement for use with a cable conveyor.

- 6 Cable conveyors comprise an endless conveyor belt which is driven by at least one endless cable which is supported between a pair of end pulleys and a set of intermediate pulleys. The cable extends for the length of the conveying system. Such conveying systems can extend for many kilometres and are regularly used 5 in the mining industry to transport ore from the mine site to the processing plant or loading centre. Whilst the conveyors can be quite effective in this role they can suffer from the difficulties as the weight of the load is approaches the upper limit of the conveyor and/or, as the speed of the system is increased and/or as the length of the conveyor is increased. One of the principle difficulties relates to 10 the amount of vibration that is generated within the system which is as a result of the cable passing over each pulley and which results in noise being generated by the conveyor. In addition the engagement of the cable with each pulley generates a significant amount of wear which requires regular maintenance of the pulleys. This wear is particularly high where the conveyor changes 15 inclination which will occur at least at the ends of inclines or declines. In addition the amount of noise and wear increases and\or as the magnitude of the load being carried by the conveyor increase, and/or as the speed of the conveyor increases and/or as the length of the conveyor increases The embodiment shown in the accompanying drawings comprises a pair of 20 pulleys where the pulleys are associated such that they will jointly support the cable. As shown at Figure 1 each pulley 11 is supported from a base 13 by a pair of radial arms 15 located to each side of each pulley. One end of each pair of radial arms 15 for each pulley are pivotally supported from the base and the 25 other end of each pair of arms support the axle 17 of the pulley. The support for the axles 17 is provided through a slot shaped recess provided in the upper edge of each radial arm 15. This enables a pulley to be disengaged from the pair of radial arms 15 by lifting the axle 17 of the pulley out of the recesses 19. In addition the pair of pulleys support between themselves an endless length of a 30 belt 21. The circumference of the belt 21 is such that when the belt is received - 7 over the pair of pulleys, the spacing between the axles 17 of the pulleys is less than the spacing that would exist if the axes of the radial arms 15 were substantially co-linear. In addition when the belt is engaged on the pulleys the axes of each of the pairs of arms defined between the central axis of the 5 respective pulley and the respective pivot axis of the arms on the base are upwardly divergent.. Because of the upward divergent nature of the arms relative to each other the belt will be tensioned as a result of the weight of the conveyor belt and the load carried thereby The belt as shown at Figures 3 and 4 is formed with a central recess 23 which 10 extends for its length and which is configured to receive the cable 25 which is used to drive the conveying system. In one arrangement and as illustrated at Figure 6, a pair of sets of pulleys according to the embodiment are supported from a support 27. In use, as the cable 25 passes over the pulleys it becomes engaged with the belt 15 21 which is supported by the pulleys and as a result the belt is caused to move with the cable 25 and in so doing rotates the pulleys 11. The belt 21 provides a platform which supports the cable and in providing such support there is little if no relative movement between points of contact of the cable 25 with the belt 21. Therefore the likelihood of vibration as a result of the passage of the cable over 20 the pulleys 11 is reduced significantly which will mean that less noise is likely to be generated and significantly less wear likely is likely to be incurred on both the belt and the pulleys. When it becomes necessary to service a set of pulleys according to the embodiment, the cable is lifted out of engagement with the belt and the arms are 25 pivoted upwardly and relatively towards each other to enable the removal of the belt. In the absence of the belt the arms can be permitted to pivot downwardly and relatively away from each other. The degree of pivotal movement is limited by stops 29 provided on one arm which will engage with the other arm when at their lowermost position as shown at Figure 2. When in this condition the pulleys - 8 are readily capable of replacement and a new belt can be subsequently applied if required. In addition were a conveyor is caused to change direction as a result encountering the beginning or end of an incline or decline, a number of sets of 5 pulleys according to the embodiment can be mounted in closely spaced relationship along the path at that location in order to provide for increased support for the cable at those locations and in order to accommodate for the increased loading exerted thereon. It is also anticipated that increasing the loading of the conveyor system within the 10 confines of the structural integrity of the conveying system will not result in a significant increase in vibration, noise or wear. It is believed the conveyor pulley arrangement of the embodiment will provide a number of significant benefits which will comprise: 1. a significant reduction in the magnitude of the noise which is generated by 15 the passage of the cable over the pulley; 2. a reduction in wear on both the cable, cable splice and the pulley with only a small amount of wear on the belt; 3. a capacity to increase the load which can be carried by the conveying system; 20 4. a capacity to increase the length of the conveying system; 5. a reduced likelihood of spillage of material from the conveyor due to the reduced vibration of the conveyor belt which is driven by the cable; and. 6. a capacity to increase the speed of the conveying system.

- 9 It should be appreciated that the scope of the present invention need not be limited to the particular scope of the embodiment described above.

Claims (10)

1. A cable conveyor pulley arrangement comprising a plurality of pulleys supported from a base such that their axes of rotation are parallel and 5 their rotation paths are substantially coplanar, an endless flexible belt member supported over the pulley to extend between the endmost pulleys to be caused to rotate with rotation of the pulleys, the outer surface of the belt being adapted to receive and support the at least one cable of the cable conveyor. 10

2. A conveyor pulley arrangement as claimed at claim 1 wherein the outer face of the belt is configured to provide a groove which will receive the cable.

3. A conveyor pulley arrangement as claimed at any one of the preceding claims wherein the pulley arrangement comprises a pair of pulleys. 15

4. A conveyor pulley arrangement as claimed at any one of the preceding claims wherein the end-most pulleys are supported from the base whereby the weight of the conveying element bome by the end-most pulleys will increase the tension of the belt.

5. A conveyor pulley arrangement as claimed at claim 5 wherein the end 20 most pulleys are each rotatably supported from an arm member, each arm member being pivotally supported from the base and wherein the length of the belt is such as to cause the spacing between the end-most pulleys to be less than their maximum possible spacing, the arm members being supported from the base such that the axes of each arm member between 25 their pivotal support on the base and the rotation axis of the respective pulley are upwardly divergent. - 11

6. A conveyor pulley arrangement substantially as herein described with reference to the accompanying drawings.

7. A cable conveyor having two ends and an endless cable extending between the to ends, the cable supported at each end by an end pulley, 5 the cable supported intermediate the ends by a set of intermediate pulleys at least some of the pulleys being incorporated into a conveyor pulley arrangement of the form as claimed at any one of the preceding claims.

8. A cable conveyor as claimed at claim 7 wherein the at least some of the pulleys comprise the intermediate pulleys. 10

9. A cable conveyor as claimed at claim 7 or 8 wherein the at least some of the pulleys comprise the end pulleys.

10.A conveyor substantially as herein described with reference to the accompanying drawings. 15 Dated this Third day of June 2005. Harry Anthony Thomas Jones Applicant Wray & Associates Perth, Western Australia Patent Attorneys for the Applicant