WO2019097549A1

WO2019097549A1 - Return belt tracking apparatus, tracking unit and a method of re-alignment of conveyor belt

Info

Publication number: WO2019097549A1
Application number: PCT/IN2018/050759
Authority: WO
Inventors: Manoj Joseph KALLARACKAL; Harikrishnan R NAIR; Moses D
Original assignee: Thejo Engineering Limited
Priority date: 2017-11-16
Filing date: 2018-11-16
Publication date: 2019-05-23
Also published as: CN213864110U; AU2018370112A2; AU2018370112A1

Abstract

The present invention relates to a conveyor tracking apparatus, modular tracking unit and a method of re-alignment of conveyor belt. The apparatus is self-adjusting for the return or non-carrying side of conveyor belt. The tracking apparatus provides a mechanism for a quick re-centering of the return conveyor belt and eliminates lateral mis-tracking and is designed such that it is installed on top of the return belt thereby completely eliminating the possibility of carry back material coming in contact with the tracking system and jamming of the pivots. The tracking apparatus is provided with an inverted V-design d so that more tension is exerted at the edges which enables better tracking of the belt.

Description

RETURN BELT TRACKING APPARATUS, TRACKING UNIT AND A METHOD OF RE-ALIGNMENT OF CONVEYOR BELT

FIELD OF THE INVENTION

[001] The present invention relates to a conveyor belt tracking. More particularly the invention relates to apparatus, racking unit and method for aligning conveyor belt.

BACKGROUND OF INVENTION

[002] Conveyor belts are commonly used as a means for transporting loads from one location to another. The belt conveyor systems are used for bulk material handling in core industries like mines, steel plants, power plants, cement plants, aluminium plants, refineries, ports, food and dairy industries etc. In the conveyor system, the belt conveyor is the main and most expensive component, which gets damaged when it does not run true or gets misaligned.

[003] Rollers for conveyor belts are arranged such that the conveyor belt travels in a downstream belt travel direction and path. However, conveyor belts tend to mistrack laterally toward one side or the other due to various reasons. Various conveyor belt tracking devices have been developed that respond to belt mistracking to attempt to redirect the belt back to its correct travel path substantially centered on the conveyor rollers.

[004] The most common solution for mis-tracking is a self-aligning roller which consists of a standard return roller with supporting frame with a pivot such that the roller rotates on an axis about its center below the return conveyer belt. The problem with this arrangement is that the pivots gets jammed due to the sticking of the material on the belt thereby making the tracker useless. In most cases a jammed tracking device is also a major cause of mis-tracking.

[005] All the existing trackers are installed under the return belt, and hence the material sticking to the belt comes in contact with the roller surface and frame which can get inside the pivot arrangement and freeze it. Additionally, the carry back material cause build-up on the pulley surface which itself can lead to mis alignment of the belt. The carry back material is usually highly abrasive, and it can damage the tracking roller surface quickly. As explained above, tracking is necessarily a result of the traction between belt and the idlers, lesser contact provides lesser tracking force. In most of the existing systems, the idler frame has a central pivot on which it swings. However, if the pivot gets jammed due to some reason, as it happens in most cases, the tracking system becomes ineffective and sometimes it could promote mis-tracking.

[006] In the view of foregoing, there is a need for an improved apparatus and method for overcoming the short comings associated with prior arts.

SUMMARY OF THE INVENTION

[007] Accordingly, the present invention provides a conveyor belt tracking apparatus and method in accordance with an embodiment of the present invention. The apparatus includes a plurality of tracking rollers placed on a tracking arm wherein the tracking arm is fitted at bottom part of a pivot assembly such that the arm can rotate about the pivot axis, each of the tracking rollers is mounted on a roller bracket wherein the bracket is secured to the tracking arm through a locking mechanism, a pair of guide rollers connected to the tracking arm, wherein the conveyor belt when misaligned touches one guide roller of the pair of guide rollers by a conveyor belt edge to initiate a realignment mechanism such that the touch deflects the guide roller outwards thereby rotating the tracking arm about its axis such that the belt is steered back to centre due to action of pivot tracking, tilting and steering forces. [008] In an embodiment the present invention provides a modular tracking unit for a conveyor belt tracking apparatus. The tracking unit includes the tracking roller mounted on the roller bracket secured to the pair of tracking arms, wherein on sensing a misalignment of the conveyor belt the realignment mechanism is triggered to rotate the tracking arm about its axis such that the belt is steered back to centre due to action of pivot tracking, tilting and steering forces.

[009] In an embodiment, the present invention provides a method of re-aligning a conveyor belt by a conveyor belt tracking apparatus wherein the apparatus comprises a plurality of modular tracking rollers secured to a tracking arm, and a pair of guide rollers, the method comprising the steps of sensing a misalignment of the conveyor belt when one of the pair of guide rollers touches a conveyor belt edge, and triggering a realignment mechanism such that the touch deflects one of the guide rollers outwards thereby rotating the tracking arm about its axis such that the belt is steered back to centre due to action of pivot tracking, tilting and steering forces.

[0010] In an advantageous aspect, the apparatus is a self-adjusting, tracking apparatus for return or non-carrying side of conveyor belts. The tracking apparatus and method provides a mechanism for a quick re-centering a conveyor belt and eliminates lateral mis-tracking of return or non-carrying side of conveyor belt.

BRIEF DESCRIPTION OF THE DRAWINGS [0011] Fig. 1 shows a perspective view of a conveyor belt tracking apparatus in accordance with embodiment of the present invention.

[0012] Fig. la shows a front view of a conveyor belt tracking apparatus in accordance with an embodiment of the present invention.

[0013] Fig. lb shows a top view of a conveyor belt tracking apparatus in accordance with an embodiment of the present invention. [0014] Fig. lc shows a tracking unit in accordance with an embodiment of the present invention.

[0015] Fig. 2, 2a, 2b illustrates an axial movement of the return conveyor belt with respect to the tracking apparatus in accordance with an embodiment of the present invention.

[0016] Fig. 3 shows front view of the return belt tracking apparatus on top of the return belt conveyor in accordance with an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] Various embodiment of the present invention provides an apparatus, modular tracking unit and method for conveyor belt tracking. The following description provides specific details of certain embodiments of the invention illustrated in the drawings to provide a thorough understanding of those embodiments. It should be recognized, however, that the present invention can be reflected in additional embodiments and the invention may be practiced without some of the details in the following description. [0018] The various embodiments including the example embodiments will now be described more fully with reference to the accompanying drawings, in which the various embodiments of the invention are shown. The invention may, however, be embodied in different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. In the drawings, the sizes of components may be exaggerated for clarity. [0019] It will be understood that when an element or layer is referred to as being

“on,”“connected to,” or“coupled to” another element or layer, it can be directly on, connected to, or coupled to the other element or layer or intervening elements or layers that may be present. As used herein, the term“and/or” includes any and all combinations of one or more of the associated listed items.

[0020] Spatially relative terms, such as“arm,”“frame,” and the like, may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the structure in use or operation in addition to the orientation depicted in the figures.

[0021] Embodiments described herein will refer to plan views and/or cross- sectional views by way of ideal schematic views. Accordingly, the views may be modified depending on simplistic assembling or manufacturing technologies and/or tolerances. Therefore, example embodiments are not limited to those shown in the views but include modifications in configurations formed on basis of assembling process. Therefore, regions exemplified in the figures have schematic properties and shapes of regions shown in the figures exemplify specific shapes or regions of elements, and do not limit the various embodiments including the example embodiments. [0022] The subject matter of example embodiments, as disclosed herein, is described with specificity to meet statutory requirements. However, the description itself is not intended to limit the scope of this patent. Rather, the inventors have contemplated that the claimed subject matter might also be embodied in other ways, to include different features or combinations of features similar to the ones described in this document, in conjunction with other technologies. Generally, the various embodiments including the example embodiments relate to apparatus, tracking unit and method for conveyor belt tracking.

[0023] Referring to Fig. 1, la, lb and lc a tracking apparatus (100) is provided in accordance with an embodiment of the present invention. The apparatus (100) includes a plurality of tracking rollers (160) placed on a tracking arm (190) wherein the tracking arm (190) is fitted at bottom part of a pivot assembly (140) such that the arm (190) can rotate about the pivot axis, each of the tracking rollers (160) is mounted on a roller bracket (170) wherein the bracket (170) is secured to the tracking arm (190) through a locking mechanism (180), a pair of guide rollers (l65a, l65b) connected to the tracking arm (190), wherein the conveyor belt (192) when misaligned touches one guide roller of the pair of guide rollers (165 a, l65b) by a conveyor belt edge (l92a) to initiate a realignment mechanism such that the touch deflects the guide roller (165 a, l65b) outwards thereby rotating the tracking arm (190) about its pivotal axis such that the belt is steered back to centre due to action of pivot tracking, tilting and steering forces. [0024] In an embodiment the present invention provides a modular tracking unit for a conveyor belt tracking apparatus (100). The tracking unit includes the tracking roller (160) attached to the roller bracket 170 mounted on the pair of tracking arms 190 (l90a, l90b), wherein on sensing a misalignment of the conveyor belt (192) the realignment mechanism is triggered to rotate the tracking arm (190) about its axis such that the belt (192) is steered back to centre due to action of pivot tracking, tilting and steering forces.

[0025] The main frame (110) is made up of a rigid material normally steel or cast iron but could be from other materials which are strong enough for the purpose. The main frame (110) designed to support entire tracking system. The main frame (110) is generally a steel structure. It may be hollow cuboidal or cylindrical or any other rigid structure with provision of movement of telescopic arms (l lOa, 110b) provided at its both ends. At both ends of the main frame telescopic arms (l lOa, l lOb) are provided. By provision of telescopic arms (l lOa, l lOb) the tracking system may be adjusted according to the site conditions. At the distal end of telescopic arms (l lOa, l lOb) mounting brackets (130) are welded at both ends. The mounting brackets (130) is welded such that at installed position the pivot is slightly tilted from the vertical axis. The main frame (110) may be a solid structure and the telescopic arms (l lOa, 110b) being hollow structures adopted to adjust by moving over the solid main frame (110). Other adjustment mechanisms may be devised for the purpose without deviating from the scope of the invention.

[0026] The pivot assembly (140) is provided at the centre of the main frame. The pivot assembly (140) ensure the free rotation of the tracking system in case of mistracking. The pivot rotation is such that the belt is steered back to the central axis of conveyer system. The tilting of the pivot forces the leading end of the tracking arm to go down thereby resulting in more tracking force at the belt edge. A pair of adjustable movement limiters (150) is provided on the main frame to limit the rotation of the tracker on the pivot. The movement limiters (150) provided on each side of pivot assembly. In case the tracking arms move more than a predetermined the pivot assembly touches the movement limiters (150) on their respective sides. Therefore, the movement of tracking arms is also limited, which ensure smooth running of the belt.

[0027] As shown in Fig. la, a pair of tracking arms 190 (l90a, l90b) is fitted at bottom part of pivot assembly (140) such that the arms can rotate about the pivot axis. The tracking arm 190 (l90a, l90b) is essentially a rigid track on which the tracking rollers (160) can be mounted.

[0028] As depicted in Fig. lc the tracking arm 190 (l90a, l90b) is provided with a sliding mechanism in which multiple tracking roller brackets (170) can be slid in to the track according to the belt width. The roller brackets (170) are attached to tracking roller (160) using plates (l70a). The locking mechanism (180) is provided to secure the roller brackets with the tracking arm (l90a, l90b). The tracking arm is made up of a rigid material normally steel or cast iron but could be from other materials which are strong enough for the purpose.

[0029] The tracking roller (160) is essentially an idler roller which is spirally rubber lined. The spiral rubber lining is preferably inward leading. However, other suitable configuration may be devised for the purpose. The tracking rollers (160) are rotatably connected to brackets (170) and rotate on their axis. The roller brackets (170) are made up of a rigid material, normally steel, on which the tracking rollers can be mounted. The roller bracket (170) is made such that it can be slid into the groove on the tracking arm (190). [0030] In an embodiment a guide roller (165) each is provided on each side of conveyor structure as shown in Fig l-lb. The guide roller (165) is mounted on a guide roller arm (120) which is fixed to the tracking arm (190). Guide roller arms (120, 122) may be welded to guide roller (165). Other fastening mechanisms may also be used to fasten the guide roller arms (120, 122) to the tracking arm (190). There is a provision to adjust the gap between belt and the guide roller. The guide rollers are designed to be stay at a specified distance away from the belt edge during normal straight running of the conveyor. [0031] In an embodiment, the tilting of the pivot enables a leading end of the tracking arm (190) to move down resulting in more tracking force at the belt edge (l92a).

[0032] In an embodiment, a self-centering spiral (l60a) each on the rollers (160) directs the belt (192) towards the centre.

[0033] In an embodiment, a pivot rotation of the tracking arm (190) is such that the belt (192) is steered back to centre. [0034] In an embodiment, the main frame (110) having telescopic arms (l lOa,

110b) provided at ends of the main frame (110) supports the tracking apparatus (100).

[0035] In an embodiment, the pivot assembly (140) is provided at a centre of the main frame (110) wherein the pivot assembly (140) ensures a free rotation of the tracking apparatus (100) in case of mis-tracking. [0036] In an embodiment, a pair of adjustable movement limiters 150 (l50a, 150b) is provided on the main frame (110) to limit rotation of the apparatus (100) on the pivot (140) such that when the tracking arm (190) move more than a predetermined distance the pivot assembly (140) touches the movement limiters (150) on their respective sides thereby limiting movement of the tracking arm 190 to ensure smooth running of the belt.

[0037] In an embodiment, the tracking arm (190) includes a first arm (l90a) and a second arm (l90b) fitted at bottom part of the pivot assembly (140) such that the arms (l90a, l90b) can rotate about a pivot axis.

[0038] In an embodiment, the tracking arm (190) is provided with a sliding mechanism in which multiple tracking roller brackets (170) can be slid in to the tracking arm (190) according to the belt width.

[0039] In an embodiment, the pair of guide rollers (l65a, l65b) is mounted on a pair of guide roller arms (120, 122) each wherein the pair of guide roller arms (120, 122) is fixed to the tracking arm (190). [0040] In an embodiment, the pair of guide rollers 165 (l65a, l65b) are configured to stay at a specified distance away from conveyor belt edge (l92a) during normal straight running of the conveyor belt (192) wherein there is a provision to adjust a gap between belt (192) and the guide rollers (l65a, l65b). [0041] In an exemplary embodiment, the tracking apparatus (100) is installed on top of a return belt to eliminate a possibility of carry back material coming in contact with the tracking apparatus (100) as a top surface of the return belt is always clean. It uses a modular idler approach which provides interchangeability and thus reduces inventory cost.

[0042] In an embodiment, the apparatus (100) has an inverted V-design so that the apparatus (100) provides more tension at the belt edges (l92a) which enable better tracking of the belt (192).

[0043] In an embodiment, the tracking rollers 160 rotate independent to each other thereby reducing chances of jamming of rollers 160.

[0044] In an embodiment, the pair of guide rollers 165 (165 a, l65b) include a first guide roller (l65a) and a second guide roller (l65b).

[0045] In an embodiment, the first guide roller (165 a) is connected to the first arm (l90a) of the tracking arm (190) through a pair of first guide roller arms 120

(l20a, l20b) that enable movement of the guide roller (l65b) outwards when touched by conveyor belt edge (l92a).

[0046] In an embodiment, the second guide roller (l65b) is connected to the second arm (l90b) of the tracking arm (190) through a pair of second guide roller arms 122 (l22a, l22b) that enable movement of the guide roller (l65b) outwards when touched by conveyor belt edge (l92b).

[0047] In an embodiment, the present invention provides a method of re-aligning a conveyor belt (192) by a conveyor belt tracking apparatus (100) wherein the apparatus (100) comprises a plurality of modular tracking rollers (160) secured to a tracking arm (190), and a pair of guide rollers (165), the method comprising the steps of sensing a misalignment of the conveyor belt (192) when one of the pair of guide rollers 165 (l65a, l65b) touches a conveyor belt edge (l92a), and triggering a realignment mechanism such that the touch deflects one of the guide rollers (165) outwards thereby rotating the tracking arm (190) about its axis such that the belt (192) is steered back to centre due to action of pivot tracking, tilting and steering forces.

[0048] In a related embodiment, the guide roller (160) returns to original position once the conveyor belt (192) is back at centre. [0049] Referring to Fig. 2, 2a and 2b, an axial movement of the return conveyor belt with respect to the tracking apparatus is shown in accordance with an embodiment of the present invention. In Fig.2, top view 200 of the belt (192) running true with axis X is shown. When the conveyor belt laterally shifts away from its normal axis, it results in the belt misaligning or running mistracked with axis X’ and Y’ as shown in top view 200a with mis-tracked belt. If the belt laterally shifts to one side, its edge (l92a) comes into contact with the corresponding guide roller 165 (l65a, l65b), pushing it outwards and away from the normal axis of the conveyor. Further, when the belt runs laterally off the central axis of the conveyor (192) as shown in top view 200b of Fig. 2b, the belt edge comes in contact with the Guide rollers 165 (l65a, l65b) in the direction of the lateral movement of the belt (192), tending to deflect it outwards. As a result, the tracking arm (190) rotate about its axis. The pivot rotation of the tracking arm (190) is such that the belt is steered back towards the central axis of the conveyor apparatus. The tilting of the pivot forces the leading end of the tracking arm to go down resulting in more tracking force at the belt edge (l92a). The spirals on the tracking rollers also directs the belt towards the centre. As a result of these multiple forces, the belt is steered back to the centre. Referring to Fig. 3 a front view 300 of the tracking apparatus on top of the return conveyor belt is shown in accordance with an embodiment of the present invention.

[0050] In an exemplary embodiment, the invention uses a three-way approach to belt tracking that is pivoting, tilting and self-centring. To correct the mis-alignment of the belt it uses pivot tracking, tilting and self-centring forces. The tracking apparatus of the present invention is aligned to form solutions for various sizes of belting on a simple support system. Economies of scale and simplicity of design make the invention an economic option to other available apparatuses.

[0051] It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the claims.

Claims

We Claim

1. A return belt tracking apparatus (100) for conveyor belts, the apparatus

comprising:

a plurality of tracking rollers (160) placed on a tracking arm (190) wherein the tracking arm (190) is fitted at bottom part of a pivot assembly (140) such that the arm (190) can rotate about the pivot axis;

each of the tracking rollers (160) is mounted on a roller bracket (170) wherein the bracket (170) is secured to the tracking arm (190) through a locking mechanism (180);

a pair of guide rollers (l65a, l65b) connected to the tracking arm (190);

wherein the conveyor belt (192) when misaligned touches one guide roller of the pair of guide rollers (l65a, l65b) by a conveyor belt edge (l92a) to initiate a realignment mechanism such that the touch deflects the guide roller (l65a, l65b) outwards thereby rotating the tracking arm (190) about its axis such that the belt is steered back to centre due to action of pivot tracking, tilting and steering forces.

2. The apparatus of claim 1 wherein the tilting of the pivot enables a leading end of the tracking arm (190) to move down resulting in more tracking force at the belt edge (l92a).

3. The apparatus of claim 1 wherein a spiral (l60a) on the rollers (160), which rotates towards central axis of the belt, directs the belt (192) towards the centre.

4. The apparatus of claim 1 wherein a pivot rotation of the tracking arm (190) is such that the belt (192) is steered back to centre.

5. The apparatus of claim 1 further comprises a main frame (110) having telescopic arms (l lOa, 11 Ob) provided at ends of the main frame (110) wherein the main frame (110) supports the tracking apparatus (100).

6. The apparatus of claim 5 wherein the pivot assembly (140) is provided at a centre of the main frame (110) wherein the pivot assembly (140) ensures a free rotation of the tracking apparatus (100) in case of mis-tracking.

7. The apparatus of claim 6 wherein a pair of adjustable movement limiters 150 (l50a, l50b) is provided on the main frame (110) to limit rotation of the apparatus (100) on the pivot (140) such that when the tracking arm (190) move more than a predetermined distance the pivot assembly (140) touches the movement limiters (150) on their respective sides thereby limiting movement of the tracking arm 190 to ensure smooth running of the belt.

8. The apparats of claim 1 wherein the tracking arm (190) includes a first arm (l90a) and a second arm (l90b) fitted at bottom part of the pivot assembly (140) such that the arms (l90a, l90b) can rotate about a pivot axis.

9. The apparatus of claim 8 wherein the tracking arm (190) is provided with a sliding mechanism in which multiple tracking roller brackets (170) can be slid in to the tracking arm (190) according to the belt width.

10. The apparatus of claim 1 wherein the pair of guide rollers (165 a, l65b) is mounted on a pair of guide roller arms (120, 122) each wherein the pair of guide roller arms (120, 122) is fixed to the tracking arm (190).

11. The apparatus of claim 1 wherein the pair of guide rollers 165 (l65a, l65b) are configured to stay at a specified distance away from conveyor belt edge (l92a) during normal straight running of the conveyor belt (192) wherein there is a provision to adjust a gap between belt (192) and the guide rollers (l65a, l65b).

12. The apparatus of claim 1 wherein the tracking apparatus (100) is installed on top of a return belt to eliminate a possibility of carry back material coming in contact with the tracking apparatus (100) as a top surface of the return belt is always clean.

13. The apparatus of claim 12 wherein the apparatus (100) has an inverted V-design so that the apparatus (100) provides more tension at the belt edges (l92a) which enable better tracking of the belt (192).

14. The apparatus of claim 1 wherein the tracking rollers 160 rotate independent to each other thereby reducing chances of jamming of rollers 160.

15. The apparatus of claim 1 wherein the pair of guide rollers 165 (l65a, l65b) include a first guide roller (l65a) and a second guide roller ( 165b).

16. The apparatus of claim 15 wherein the first guide roller (l65a) is connected to the first arm (l90a) of the tracking arm (190) through a pair of first guide roller arms 120 (l20a, l20b) that enable movement of the guide roller (l65b) outwards when touched by conveyor belt edge (l92a).

17. The apparatus of claim 15 wherein the second guide roller (l65b) is connected to the second arm (l90b) of the tracking arm (190) through a pair of second guide roller arms 122 (l22a, l22b) that enable movement of the guide roller (l65b) outwards when touched by conveyor belt edge (l92b).

18. A modular tracking unit for a conveyor belt tracking apparatus (100), the tracking unit comprises:

a tracking roller (160) mounted on a roller bracket 170 wherein the bracket 170 is secured to a pair of tracking arms 190 (l90a, l90b);

wherein on sensing a misalignment of the conveyor belt (192) the realignment mechanism is triggered to rotate the tracking rollers (160) about its axis such that the belt (192) is steered back to centre due to action of pivot tracking, tilting and steering forces.

19. The modular tracking unit of claim 18 wherein a spiral (l60a) on the tracking rollers (160), which rotates towards the central axis of the belt, directs the belt (192) towards the centre.

20. The modular tracking unit as claimed in claim 18 wherein a locking mechanism (180) is provided on the bracket (170) to secure the tracking roller (160).

21. A method of re-aligning a conveyor belt (192) by a conveyor belt tracking apparatus (100) wherein the apparatus (100) comprises a plurality of modular tracking rollers (160) secured to a tracking arm (190), and a pair of guide rollers (165), the method comprising the steps of:

sensing a misalignment of the conveyor belt (192) when one guide roller of the pair of guide rollers 165 (l65a, l65b) touches a conveyor belt edge (l92a), and

triggering a realignment mechanism such that the touch deflects one of the guide rollers (165) outwards thereby rotating the tracking arm (190) about its axis such that the belt (192) is steered back to centre due to action of pivot tracking, tilting and steering forces.

22. The method of claim 21 wherein the guide roller (160) returns to original position once the conveyor belt (192) is back at centre.