AU645894B2 - Transition impact idler for conveyor belt - Google Patents

Description

AUSTRALIA

645894 Patents Act 1990 OR IGINAL COMPLETE SPECIFICATION STANDARD PATENT Invention Title: o 0 *0 0 0* 0* S g

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TRANSITION IMPACT IDLER FOR CONVEYOR BELT.

The following statement is a full description of this invention, including the best method of performing it known to me:- 4S 0 S S 0551 S S 55 St 5 0500 55

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5* IA TRANSITION IMPACT IDLER FOR CONVEYOR BELT Background of the Invention In US Patent 5,038,924, incorporated herein by reference, there is disclosed and claimed an improved stationary impact saddle for belt-type material conveying systems. The impact saddle described is intended as a direct replacement for conventional impact idler rollers.

T-shaped parallel supports extend in transverse relation to the direction of belt movement, and are curved to form an upwardly-facing concavity or curvature which approximates the required troughing angle of the upper run of the conveyor belt. A series of individual low-friction polymeric blocks or segments, positioned in adjacent relation on the supports and transversely of the belt, form upper surfaces which engage and support the lower surface of the belt in the impact zone.

Since the impact saddles of US 5,038,924 replace the conventional impact idler, a series of such saddles are usually positioned in side-by-side relation in the impact 20 zone. When the individual blocks or segments are worn, they are replaceable on the saadle supports, by sliding along the T-shaped support members, without having to remove the support members or the frame.

US 5,038,924 assumes an impact zone which is spaced somewhat from the tail section of the conveyor belt, in other words, at a location where the troughing *4 Docket RIB 025 P2 angle is already established. There exists, however, conveyor belt installations in which the belt loading, and therefor the impact, takes place in the transition section between the flat or straight tail pulley and the conventional troughing idlers.

Conveyor belt systems use a transition section at the tail piece to form the desired troughing angle in the upper run, since it is not practical to go directly from the flat tail pulley to a troughing idler. Such transition 1 0 sections commonly use conventional three roll idlers to form up the belt in the transition section, in which the two outside rolls are set at increasing angles, from essentially flat or low angle condition at the tail pulley, to the desired belt troughing angle at cnd of the transition section. This is ordinarily accomplished by five to seven idlers, spaced about twelve to eighteen inches apart. Where the impact is on the tail piece, impact-type transition S. roller idlers are commonly used, that is, idlers in which "the support rolls are made from an impact absorbing 20 material. A typical example consists of the types HG and HS of Continental Conveyor Equipment Company, Inc., of S" Windfield, Alabama 35594. However, roll-type idlers tend to make only line contact with the belt with the result that large areas of the belt are unsupported and subject to damage from falling material.

Using impact saddles of the general type as shown u S S,03,%i- pro ,h e and described in ndg pplition, have a solution to the problem of low-friction impact support at the transition section of a bulk material conveyor belt.

3- Summary of the Invention According to one aspect of the present invention there is provided an impact saddle for use in the transition section of a belt-type bulk material conveyor, in which the belt moves over a tail pulley and is transitioned to a desired troughing angle, comprising: a support frame adapted to be positioned in said belt transition section, said frame having an upper impact segment supporting member extending transversely of said belt, said member being curved to form ends positioned adjacent the lateral sides of said belt which ends are elevated in relation to the middle of said member, said member being formed with generally parallel sides with one of said sides positioned farther from said tail pulley than the other side, said one side being defined by a radius of curvature which is less than the other side, a plurality of low friction polymeric block-type belt support segments mounted on said supporting member, said segments each having an upper belt-supporting surface, the upper surfaces of said segments being inclined by said member to define a portion of the change in belt angle o• 'between the flat condition at said pulley and the final S belt troughing angle.

According to another aspect of the present invention there is provided an impact slider-type idler for use in the transition section of a bulk material belt conveyor, for supporting the belt against the impact of the material to be conveyed and, at the same time, guiding the belt from the tail pulley of the conveyor into a desired 30 troughing angle, comprising: a plurality of support members extending transversely of the direction of said belt and in side-byside relation, each of said members having means thereon defining an upper transversely curved belt engaging polymeric surface extending the width of said belt, said support members each defining at said polymeric surfaces curvatures of progressively smaller radii with increasing 4 spacing from said tail pulley for forming said belt into said troughing angle.

It is preferable to use parallel T-shaped supports and individual polymeric blocks or segments carried on the supports. It has been found that the same bloc!-. may be used, that is, blocks which are formed with a dot b;.i T-shaped slot for threading onto the corresponding T-shaped frame supports, with the T-shaped frame supports configured to support the segments in a close approximation of a desired transition angle.

It is a characteristic of the preferred embodiment of the conveyor that the lowest or deepest part of the trough formed by the belt is substantially coincident with or level with the off-running side of the tail pulley. Therefore, a longitudinal section through the centre of the transition section, that is, in the direction of belt movement, shows that the upper surfaces of the segments form a straight line. The trough may be formed by of.. progressively elevating the lateral or opposite sides of 20 the belt, until they form the desired troughing angle with "the belt centre, which may be from 200 to 300, and sometimes as much as 450, to the horizontal.

S The total elevation may be made by providing an incremental elevation at each of the parallel T-supports of the frames. The tops of the support T's themselves are epreferable inclined at a transition angle (at all transverse positions from the belt centre) so as to support each polymeric segment with the off-running edge elevated with respect to the on-running edge. In this manner, a 30 smooth and uniform transitional support may be provided for the belt, and the belt is then better protected from injury due to the impact of loading at the transition section.

It is preferred that individual impact saddles a'e provided having polymeric sliding surfaces which may provide a direct substitute for an existing idler roll frame assembly. The spacing, in the direction of belt movement, may be such as to place adjacent support saddles 9: 5 with the blocks or segments in abutment, to form a continuous slider surface, or the saddles could be spaced according to the spacing of the existing idler roll frames, in which case a gap or space could be formed between adjacent belt support surfaces. However, a continuous slide surface is preferred for maximum belt protection.

Brief Description of the Drawings Preferred embodiments of the present invention will hereinafter be described by way of example only, with reference to the accompanying drawings, in which: Fig. 1 is a perspective view of the transition end of a belt-type conveyor which is also the load impact region, and illustrating the employment of the transition saddles of a preferred embodiment of this invention for supporting the belt and forming the belt troughing angle; Fig. 2 is a longitudinal sectional view through the transition impact slider-type idler according to a preferred embodiment of the invention with the section being taken through the common low point of the curve; 20 Fig. 3 is a plan view of the transition idler of S* the preferred embodiment of this invention; Fig. 4 is an end view of the transitional idler oS 5 .looking along the view line 4--4 of Fig. 3; and Fig. 5 is a side view of one of the transition saddles looking generally along the view line 5--5 of Fig.

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Description of Preferred Embodiment With reference to the drawings, which illustrate a preferred embodiment of the invention, a belt-type 30 conveyor for carrying bulk material, such as crushed coal, gravel, crushed limestone, or the like, includes a conveyor belt 10. The belt 10 is shown in Fig. 1 and turning at the tail piece 12 about a flat or straight tail pulley 15 from a lower run Docket RIB 025 P2 -6- 16 into an upper run 17. As previously described, it is not practical to form the belt 10 directly into a desired troughing angle without the use of an intermediate or forming section, usually consisting of three-roll type idlers, a typical example being the roll-type idler shown at in Fig. 1.

Such roll-type idlers are quite satisfactory in the transition section where the loading zone in well offset from the tail piece 12. However, Fig. 1 further illustrates '10 a condition where the belt 10 is loaded by bulk material :directly in the transition section or zone, identified by o. the brackets 25, while the belt is being formed from the flat condition at the tail pulley to the final troughing

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angle at the roll idler 20, pre 'e~cc e boc\> me( o- tr' 0 015 The invention provides an impact slider by which the transition is made, and the belt is supported as in a loading zone. For this purpose, a progression of impact saddles 30 are used, each defining and forming a discrete S0:" portion, segment, or part of the total trough angle for the 0 particular belt installation.

Each saddle 30 has a support frame 32 formed in two halves, namely a right-hand (upstream) support frame section 32a and a left-hand (downstream) support frame S. section 32b, as best shown by the end view of fig. 5. The frame sections 32a and 32b are mounted with end flanges 34 *o in abutting and welded relation, and are formed with outwardly extending feet 35 by which the frame 32 may be secured or attached to a suitable base or support.

The halves 32a and 32b have vertically extending support webs or portions 36 which terminate in a pair of generally parallel, side-by-side T-shaped support members

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I 1 cr. Docket RIB 025 P2 and 40b. The members 40a and 40b have the same elevation and are held normal to the associated web 36 at the transverse center of the belt path, that is, the low point of the saddle. At the opposite ends, however, the Tshaped members are inclined at a common inclination angle a and the member 40a is elevated in relation to the member so that the T-members are in a straight line to each other.

The T-shaped support members are also curved 10 transversely of the width of the frame 32, with the concavity facing upward. For ease of manufacture, the curve may be in the form of a simple segment of a circle to approximate a troughing angle or an intermediate angle. It is characteristic of the conveyor that the lower-most 15 surface of the belt at the center of the belt, usually remains on a level with the top or off-running side of the pulley 12, while, in the transition zone, the belt lateral sides become progressively elevated until the final troughing angle is obtained. Accordingly, where the 0 curvature is represented as a segment of a circle, it will 0. be seen that the curvature of the supports 40 counting from the pulley 15 toward the roll-type idler, will be represented by decreasing radii in each such support.

The belt running surface is defined by individual polymeric segments or blocks 45 threaded on the pairs of Tshaped supports 40. The blocks 40 may be identical to the corresponding blocks or segments 30 as more fully described S 5/ig/^2t in| o-pndin application. They are preferably formed of a high molecular weight polyethylene, and have a lower surface which defines a pair of laterally spaced generally T-shaped slots or openings 47 proportioned to receive the Docket RIB 025 P2 -8supports 40a and 40b. The segments 45 may be isolated by thin pads or blocks 48 of rubber material.

The segments 45 may be identical to each other, and may have planar upper belt-engaging surfaces 49. In use, the segments are threaded onto the supports and are stacked transversely of the belt against each other, so that the upper surfaces approximate a particular curve. Since the support 40a is elevated, with increasing distance from the center, in relation to the support 40b, the blocks are more progressively tilted so that their collective surfaces 49 form an approximation of a surface of revolution with a decreasing diameter with increasing distance from the tail pulley.

Therefor, in use, a plurality of the! support L5 frames or saddles 30 are used, such as six as illustrated in Fig. 1, each with a different curvature to accommodate a segment or an increment of the total angle. For example good results have been obtained a 30" troughing angle, for an impact transition zone, by the use of five saddles, the 20 first providing a 5°-7 change, the second a 10'-13' change, 6the third a 16*-18" change, the fourth a 22°-24' change, and Sthe fifth a 27'-30° change.

When the segments 45 are in place, they may be retained by clips 50 and bolts 52. Worn segments may be replaced by removing the clips, driving on new segments 6. 0* which push the worn segments off the opposite side.

The practice of the invention is largely selfevident from the foregoing description. A suitable progression of saddle supports is chosen to form the belt into the required troughing angle, and positioned in the transition zone 25. Usually, the individual saddles 30 will 9 form a direct substitute or replacement for existing threeroll impact type idlers formally in the zone. However, it is in the scope of the invention to provide a slider for the transition zone in new belt installations.

The transition idler of the preferred embodiment of this invention not only increases the troughing angle from flat to the desired angle over a series of succeeding steeper angled idlers, but each separate idler is angled from flat in the centre to an angle at the opposite edges that corresponds to the angle the belt will take over the length of the transition area. The arrangement provides a smooth low-friction bed for the belt to transverse.

While the form of apparatus herein described constitutes a preferred embodiment of this invention, it is to be understood that the invention is not limited to this precise form of apparatus, and that changes may be made therein without departing from the scope of the invention.

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Claims (10)

1. An impact saddle for use in the transition section of a belt-type bulk material conveyor, in which the belt moves over a tail pulley and is transitioned to a desired troughing angle, comprising: a support frame adapted to be positioned in said belt transition section, said frame having an upper impact segment supporting member extending transversely of the- 4wi4dth-of said belt, said member being curved to form ends positioned adjacent the lateral sides of said belt which '*10 ends are elevated in relation to the t-ranver-s middle of said member, said member being formed with l ter 11y spaeA generally parallel sides with one of said sides positioned a 0. farther from said tail pulley than the other side, said one side being defined by a radius of curvature which is less 15 that the other said side, a plurality of low friction polymeric block-type belt support segments mounted on said supporting member, *a said segments each having an upper belt-supporting surface, the upper surfaces of said 'egments being inclined by said 20 member to define a portion of the change in belt angle between the flat condition at said pulley and the final belt troughing angle.

2. The impact saddle of claim 1 in which said segments are formed of high density material.

3. The impact saddle of claim 1 in which said segments are identical and in which said upper surfaces are planar. t m Docket RIB 025 P2 -11-

4. The impact saddle of claim 1 in which said segment supporting member comprises a pair of side-by-side parallel T-shaped supports one each defining one of said parallel sides, and in which said segments are formed with a pair of T-shaped slots, one each adapted to receive one of said T- shaped supports therein and providing for the threading of said segments onto said supports.

The impact saddle of claim 4 in which said segments are threaded on said T-shaped supports in end-to- end abutting relation, and in which said upper surfaces collectively form a partial transition angle for said belt. 0*

6. An impact slider-type idler for use in the transition section of a bulk material belt conveyor, for supporting the belt against the impact of the material to be conveyed and, at the same time, guiding the belt from the b5 tail pulley of the conveyor into a desired troughing angle, comprising: a plurality of support members extending transversely of the direction o-f movement of said belt and in side-by-side relation, each of said members having means thereon defining an upper transversely curved belt engaging polymeric surface extending the width of said belt, said support members each defining at said polymeric surfaces It curvatures of progressively smaller radii with increasing spacing from said tail pulley for forming said belt into said troughing angle. r O 12

7. The impact saddle of claim 6 in which said upper surface defining means comprises a plurality of substantially identical polymeric blocks each having an upper belt-supporting surface, and said support members having means for supporting the said blocks thereon in side-by-side relation transversely of said belt.

8. The impact saddle of claim 7 in which said means for supporting said blocks comprising a pair of T-shaped supports extending transversely of said belt, said supports being inclined at positions spaced transversely of the belt centre to define an incremental change in said troughing angle, and said blocks having slot means proportioned to receive said T-shaped supports therein permitting the threading of said blocks onto said supports for a position at one side of said belt.

9. An impact saddle for use in the transition section of a belt-type bulk material conveyor substantially as herein described with reference to the accompanying drawings. 20

10. An impact slider-type idler for use in the transition section of a bulk material belt conveyor substantially as herein described with reference to the accompanying drawings. DATED THIS 18TH DAY OF NOVEMBER 1993 25 RICHWOOD INDUSTRIES, INC._ By Its Patent Attorneys: S" GRIFFITH HACK CO., Fellows Institute of Patent Attorneys of Australia .U Docket RIB 025 P2 Abstract of the Disclosure An impact slider-type idler for use in the transition section of a bulk material conveyor supports the belt against the impact of material to be conveyed in the transition section and, at the same time, guides the belt from the tail pulley of the conveyor into the desired troughing angle. The slider of this invention employs a plurality of support members extending transversely of the direction of movement of the belt, in side-by-side relation. The support members are formed with T-shaped supports along the upper surface, which supports are inclined to define an C increment of change in the troughing angle. Each of the support members carries on the T-shaped supports polymeric segments or blocks which extend transversely of the belt. 15 The angle formed by each section progressively supports the belt between the flat condition as it leaves the tail pulley to a fully troughed position as it exits the transition zone. 0 0*