AU651377B2 - Improvements in or relating to conveyors - Google Patents

Description

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AUSTRALIA

Patents Act COMPLETE SPECIFICATION (ORIGINAL) 67 Class Int. Class Application Number: Lodged: Complete Specification Lodged: Accepted: Published: Priority Related Art: SName of Applicant: G. R. Patton Engineering, Ltd.

Actual Inventor(s) 9ao- 00 Gavin George Patton Address for Service: PHILLIPS ORMONDE FITZPATRICK Patent and Trade Mark Attorneys 367 Collins Street Melbourne 3000 AUSTRALIA t Invention Title: IMPROVEMENTS IN OR RELATING TO CONVEYORS 9** Our Ref 229638 POF Code: 1358/151479 t'i The following statement is a full description of this invention, including t« the best method of performing it known to applicant(s): 600 6006 2 This invention relates to conveyors in which the conveying surface is an endless succession of rollers. More particularly the invention relates to a conveyor corner.

It is difficult to move a product smoothly around a corner on a conveyor on which is it riding without having it thrown off by centrifugal force or, if means are provided to stop this, having it jamming up, thereby damaging the product. Damage to the product can be caused by the product being crushed in the ensuing pile-up or by friction between the halted product and the still moving conveying surface underneath. In most cases the conveyor itself has to be turned off so that the pile-up can be 0 cleared. The result is time and prodiuc losses in the operation.

«It is an object of this invention to provide a conveying apparatus that goes some way towards overcoming these disadvantages or at least to offer the public a useful choice.

Accordingly, the invention may be said broadly to consist in a conveyor corner comprising: v a frame defining a curved pathway, said curved pathway having a centre of curvature; a conveyor comprising an endless succession of rollers arranged to travel along said curved pathway; a pair of wheels rotatably mounted on said frame at ia the/,end of Ssaid curved pathway, each said pair of wheels comprising an inner wheel nearer to said centre of curvature and an outer wheel further from said centre of curvature; an endless flexible connector at each end of each said roller, said flexible connector nearer said cfntre of curvature passing over each said inner wheel and said flexible connector further from said centre of curvature passing over each said outer wheel; and i i

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3 o 09 o 9* 0 0 I Ij II 4 4 *0* 4 *0 0 0e drive receiving means drivingly connected to at least one of said pairs of wheels at at least one end of said curved pathway; wherein each said inner wheel has more teeth than each said outer wheel, the diameters of said inner and outer wheels are substantially equivalent and the ratio of the number of teeth on each said inner wheel to the number of teeth on each said outer wheel is the same as the ratio of the speed at which said outer wheel is driven to the speed at which said inner wheel is driven; the arrangement being such that in use when said drive receiving means is driven it rotates said at least one pair of wheels, said inner wheel and said outer wheel being indepedentydriven at different rotary speeds at said ratio, to thereby simultaneously drive said endless connectors and said endless succession of rollers whereby an article on said rollers may be conveyed along said curved pathway.

Preferably said rollers are aligned along the radii from said centre of curvature.

Preferably each of said rollers is rotatable about its central longitudinal axis.

Preferably there are provided end pieces at each end of each said roller, said flexible connectors being joined to said end pieces.

Preferably each said flexible connector passes through a bore in each said end piece,at its side of Waid eurved pathway.

Preferably a shaft projects from each end of each said roller, said shaft being mounted in a said end piece.

Most preferably there is a common shaft in each said roller, one end of which projects from either end of said roller.

Preferably said frame includes inner and outer curved sides defining the curved pathway therebetween.

%fI It t I II 4 Preferably there are rollers on vertical axes on the inside faces of said curved sides.

Preferably there is provided a guideway on the inner face of each of said outer and inner curved sides in which said end pieces are guided.

Preferably said wheels over which said flexible connectors pass are sprocket wheels, Preferably said flexible connectors are each synthetic cables.

The invention may also be said broadly to consist in a conveyor corner substantially as herein described with reference to the accompanying drawings.

CC" The invention may be more fully understood by having reference to the ,0 accompanying drawings in which: Figure I is a top plan view of a preferred embodiment of the a.C invention.

Figure 2 is the sectional view II-II in Figure 1.

Figure 3 is the sectional view Ill-Ill in Figure 1.

Figure 4 is the sectional view IV-IV in Figure 1.

Figure 5 is a side elevational view of an end piece.

Figure 6 is an end elevational view of an end piece.

Figure 7 is an end perspective view of the upstream end of a corner conveyor according to the invention.

Figure 8 is an end elevation of the end of the corner conveyor with the rollers, end pieces and flexible connectors removed.

Figure 9 is a schematic side elevational view of a drive means embodiment looking towards the conveyor frame side.

Figure 10 is a top plan view of the drive means of Figure 9.

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Figure 11 is an elevational view of the drive means of Figures 9 and viewed from downstream looking upstream.

Figure 12 is a top plan view of a preferred embodiment of the invention not showing the features of Figure 1.

Figure 13 is a side elevational view of the outside side of Figure I12.

i Figure 14 is a side elevational view of the inside side of Figure 12.

Figure 15 is an elevational view of the gearbox drive of Figure 12.

Figure 16 is the sectional view x-x in Figure 10 In the preferred embodiment shown in Figure 1 a curved pathway is I defined by a frame, two components of which are sides 12 and 23. An S l endless succession of rollers 10 are conveyed by cables 15 and 17 at either end thereof along the pathway defined by the sides 12 and 23. The cables 15 and 17 may be nylon rope3 or any other suitable flexible connector. At either end of each roller 10 there is provided an end piece 14. The construction of the end pieces will be further described with r reference to figures 5 and 6. In operation the rollers 10 plus end pieces 14 act as pacers to keep the cables 15 and 17 at the correct distance apart and therefore rollers 10 should all be substantially the same length.

At the upstream end of the conveyor corner there is provided an idler

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roller 18 which is mounted to the frame sides 12 and 23 and is, in the preferred embodiment illustrated, free'ly rotatable. Similarly at the downstream end of the corner there is also provided a freely rotatable roller 28.

At the upstream end of the conveyor corner there is provided an inner sprocket wheel 22 and an outer sprocket wheel 20, the diameters of each being substantially the same and each mounted on a stub shaft 36.

-6- Similarly at the downstream end of the corner there is provided an equivalent pair of sprocket wheels 24 and 26. These are also each mounted separately on stub shafts 36 and 47. The stub shafts are themselves each mounted in a boss on opposite sides 23 and 12 of the frame of the apparatus. The positions of each of sprocket wheels 20 and 22 are adjustable with respect to the frame of the apparatus so as to take up independently any slack in either cable 15 or 17.

Sprocket wheels 20 and 22 as illustrated in Figures 2 and 3 each have indentations 16 between adjacent teeth, five on sprocket wheel 20 and seven on sprocket wheel 22. The radius of curvature of these indentations 16 is slightly larger than the radius of curvature of each end piece 14 which rests in the recess while the cable 15 is passing around the wheel amci 20. The distance from the centre of each sprocket wheel 20 and 22 to the 60 o LnO °bottom of each indentation 16, is substantially the same. Sprocket wheels 26 and 24 are respectively substantially equivalent. The ratio of the number of teeth on each inner wheel (correspQnds to the number of indentations 16) to the number of teeth on each outer wheel is therefore 7:5, ie. 1.4:1.

As is best seen in Figure 4 each roller 10 is hollow and fitted with an end disc 11 having a central bush portion 19. The opposite ends of central shaft 13 extend through bush portions 19 at either end of roller and rest in bore 66 of end piece 14 (see Figure When a roller is passing over a sprocket wheel 20, 22, 24 or 26 the loose fit in bore 66 allows each end piece 14 to bend out of alignment with its shaft 13. This is shown in Figure 7.

Also visible in Figure 2 is an upper guideway in side 12 having a top member 40 and a lower member 42 in which advancing end pieces 14 moving in the direction of arrow B travel. Similarly a lower guideway 44 is provided along which the end pieces 14 ride in the direction of arrow A.

n 1L1 i i i Referring to Figure 1, it will be seen that the rollers 10 lie with their axes substantially along radii from the centre of curvature C of the current pathway. Rollers 10 are closer to each other at their ends nearer side 23 than at their ends nearer side 12. The roller construction illustrated is the same as that in Figure 2.

There are illustrated, as well, guideways on side 23 of the conveyor path. The upper guideway consists of a top member 52 and a lower member 54. The lower guideway has a singe member 56. Again the guideways guide end pieces 14.

Referring to Figure 4, it will be seen that there is a frame cross 0 a member 58 between frame sides 23 and 12. There is illustrated in the upper portion a roller 10 on a conveying lap while at the bottom there is a roller 10 on a return lap. The upper and lower guideways described with reference to Figures 2 and 3 are also illustrated in Figure 4.

The end pieces 14 are illustrated in detail in Figures 5 and 6. Each end piece 14 is substantially cylindrical in shape but has a flat 68 along ,,its bottom. A central bore 66 along its longitudinal axis provides a socket in which in operation each shaft 13 rests. The bore 66 is oversized with respect to shaft 13 so that there may be some play in the positioning of the end of shaft 13 in bore 66. A bore 72 at right dngles to bore 66 is drilled across each end piece 14. It is of diameter slightly larger than each of cables 15 and 17. A bore 69 is tapped a a bolt 70 of corresponding thread is bolted home into bore 69 so as to pass across part of bore 72 to press cables 15 and 17 into position. End pieces 14 are preferably made of self-lubricating plastics material, such as polyethylene, so as to reduce friction while sliding in their respective guideways. Ir 8 The end pieces 14 are secured into position by tightening bolts 70 in a preferred embodiment so that the longitudinal axis of each roller lies along a radius from curvature centre C, As is shown in Figures 4 and 7 there are provided in a preferred embodiment roller assemblies along the inner faces of the sides 12 and 23. Each assembly comprises a bracket 50 in which is rotatably mounted a roller 51.

One alternative driving assembly is illustrated in Figure 8.

Sprocket wheel 26 is mounted for rotation with stub shaft 36. Stub shaft 10 36 is bearingly mounted through side 12 in boss 46. Also sprocket wheel 24 is mounted for rotation with stub shaft 47 which is bearingly mounted through side 23 in a boss 48. A universal shaft 30 has universal joints S" ,32 and 34 at either end connecting it with the two stub shafts 36 and 37.

An extension 38 of stub shaft 37 is bearingly mounted through stub shaft 47 and forms the main drive receiving shaft for sprocket wheel 26.

In operation shafts 38 and 47 are interdependently driven through drive means from a suitable prime mover such as an electric motor. Drive is transmitted to sprocket wheels 24 and 26. These in turn drive the end pieces 14, cables 15 and 17, and rollers A drive means embodiment, suitable for incorporating with the driving asseimbly illustrated in Figure 8, is illustrated in Figures 9, 10 and 11.

Figure 9 shows the gearbox housing 78 mounted against the conveyor frame side 23. The housing 78 is mounted on a gearbox mounting 89 which is welded to the side 23. A drive chain 76 transmits the drive from the prime mover, or from an adjacent conveyor, via a 19mm pitch sprocket 77 to a counter shaft 87 on which runs the driven sprocket 77 and a 42T helical gear 79. The axis 88 of the counter shaft 87, centre 81, is offset from the axis 86 of the gearbox, off centre 80, so as to be parallel to the front of the conveyor. This allows for counterdriving off the tail of another S conveyor. For example,

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4 q ~LI \AQ .9 to allow the corner conveyor illustrated to be counterdriven from a straight conveyor the centres 80 and 81 are offset 60. The helical gear 79 drives up to a double gear, at one end a second 42T helical gear 82 and at the other end a 36T spur gear 83, Made from a high wear plastic. This double gear transmits the drive independent ytto the two conveyor sprockets 24 and 26. The first gear train drives from the helical gear 82 to a 30T helical gear 84 through the buswied hub of 7T sprocket wheel 24, through the universal shaft 30 (as shown in Figure 8) to the 5T sprocket wheel 26. This drives the 5T sprocket wheel 26 at an increased speed of 1.4:1. The second gear train drives from the spur gear 83 to a second 36T spur gear 85, bearingly mounted on the same extension 38 as helical gear 84, directly to the 7T sprocket wheel 24 at a ratio of 1:1.

The view illustrated in Figure 10 further shows the gearing relationship described for Figure 9. The shafts along axes 86 are bearingly mounted in the gear box housing 78 and are offset 60 from the axis 88 of counter shaft 87. Spur wheel 85 is bearingly mounted on extension 38 and stub shaft 47 is bearingly mounted through side 23 and gear box housing 78 in boss 48. Figure 10 shows how 7T sprocket wheel 24 is driven by 36T spur wheel 85 while ST sprocket whe~el 26 (not shown) is driven independently by 30T helical gear 84 Via extension 38 to stub axle 37.

Figure 11 further shows how sprocket wheels 24 and 26 are independe-nUL.driven and the relationship between the gear drive wheel sprocket 77 and gear 79 and the gearing ratio wheels gears 82, 84 und Figures 12-16 show an-alternative embodiment where the drive means is on the opposite side to the gearbox housing 78. The drive means 90 has a motor mount and guard 91 and transmits drivt; to the outer bearing shaft within outer bearing housing 52,. through universal shaft 30 to the inside gearbox drive 94.

Figure 15 shows the general layout of the gearbox drive 94, which is basically the layout in Figure 11 without the counter shaft 87 and associated sprocket 77 and gear 79. Sprocket wheel 24 is not shown.

Figure 16 shows the connection from the 30T gear 84 to the 42T gear 82, which is one end of the double gear shown in Figure 10. At the other end (not shown) is the 36T spur gear 83 which transmits the drive to the second 36T spur gear 85 and thence to the 7T sprocket wheel 24. As the sprocket wheel 26 is driven directly from the drive means 90, through being clamped to the outer bearing shaft, the speed differential of 1.4:1 between sprocket wheels 26 and 24 is maintained. With this arrangement it is not necessary for the gears 84 and 82 to be helical but helical gears may be necessary if the drive means originates from an adjacent conveyor, *Figures 13 and 14 show the general arrangement of the embodiment in Figure 12 from side elevations. Shown is the conveyor, depicted as frame sides 12 and 23, supported by legs 98 with the drive means 90 situated near and under the front of the conveyor. Also shown is adjustment plates j 96 which provide adjustment to corrc t the tension in cables 15 and 17.

It is necessary that there is a common ratio between the gearing ratio wheels 82 and 84, the speed of rotation of sprocket wheels 24 and 26, the speed that the endless connectors 15 and 17 travel and the number of teeth on sprocket wheels 24 and 26. That ratio can be determined as being the ratio of the upper path length followed by the outer endles( connector 15 to the upper path length followed by the inner endless connector 17. The upper path length in both is the distance along the curved pathway between a first radius and a second radius from the centre of curvature of the curved pathway, Referring to Figure 1 the common ratio can be the ratio of the length of the curve,. path followed by endless cable 15 between point A and point D to the length of the curved 11 I path followed by endless cable 17 between points B and E (as shown in Figure C is the centre of curvature of the conveyor corner. An imaginary line CBA is one radius from the centre C while an imaginary line CED is another radius from the centre C.

In the embodiments shown that common ratio is 1.4:1.

An article fed by a conveyor upstream of idler roller 18 conveys the article (for example a box 74 as illustrated in Figure 7) onto the upper surfaces of rollers 10. The rollers then advance the box 74 around the corner and discharge it over idler roller 28 onto a downstream conveyor or 10 other conventional destination. The rollers 10 move at the same angular speed around the corner and articles 74 on the top surfaces do not slide S outwardly or inwardly owing to the differences in radial speed from one end to tho other end of the rollers. If the conveyer is to be operated at a higher speed it may be preferable to lower wheels 22 and 24 so that in use the upper surface of rollers 10 slope upwardly from the inside to the outside of the corner to counteract the centrifugal force on objects going around the corner.

In the preferred embodiment illustrated, the rollers are themselves rotatable about their respective axles 13. If an obstruction is encountered downstream on the conveyor system so that articles riding along the tops of the rollers are obstructed, the rollers underneath the t articles simply rotate as they pass beneath the articles so that drive is not interrupted. When the obstruction is removed and articles are able to continue the inertia caused by the weight of the articles is sufficient to commence movement again. Rollers 51 assist in moving articles 14 resting against sides 12 and 23.

12- The main advantage of the above described conveyor is that a product is conveyed around a corner without any driving force being applied directly to the product, thus allowing the product to inaintain a true line. In most cases that line would be along the centre line of the corner conveyor. Another advantage is that the conveyor, conveying a product arc.,id the corner, allows the product to be stopped anywhere on that corner, without damaging the product and without turning the conveyor off.

Although preferred embodiments of the present invention have been 10 shown, it is obvious that modifications and variations of the present t1 Il t invention are possible in light of the above teachings. It is therefore to be understood that the present invention may be practiced otherwise

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Th than as specifically described and that it is only to be limited by the inscope of the appended claims.

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Claims (10)

1. A conveyor corner comprising: a frame defining a curved pathway, said curved pathway having a centre of curvature; a conveyor comrrising an endless succession of rollers arranged to travel along said curved pathway; a pair of wheels rotatably mounted on said frame at i-theprend of said curved pathway, each said pair of wheels comprising an inner wheel 13 nearer to said centre of curvature and an outer wheel further from said centre of curvature; i an endless flexible connector at each end of each said roller, said o flexible connector nearer said centre of curvature passing over each said inner wheel and said flexible connector further from said centre of curvature passing over each said outer wheel; and drive receiving means drivingly connected to at least one of said pairs of wheels at at least one end of said curved pathway; wherein each said inner wheel has more teeth than each said outer wheel, the diameters of said inner and outer wheels are substantially equivalent and the ratio of the number of teeth on each said inner wheel to the number of teeth on each said outer wheel is the same as the ratio i of the speed at which said outer wheel is driven to the speed at which said inner wheel is driven; the arrangement being such that in use when said drive receiving means is driven it rotates said at least one pair of wheis, said inner wheel and said outer wheel being i.ndepen. t-dl, driven at different rotary speeds at said ratio, to thereby simultaneously drive said pair of endless connectors and said endless succession of rollers whereby an article on said rollers may be conveyed along said curved pathway. L 4 -14-

2. The conveyor corner according to claim 1 wherein said rollers are aligned along radii from said centre of curvature.

3. The conveyor corier according to claim 1 or 2 wherein said flexible connectors are joined to end pieces provided at each end of each said roller.

4. The conveyor corner according to claim 3 wherein a sh=ft projects from each end of each said roller, said shaft being mounted in a said end piece.

5. The conveyor corner according to claim 3 or 4 wherein there is provided a guideway on each side of said curved pathway in which said end pieces are guided.

6. The conveyor corner according to any one of claims 1 to wherein said flexible connectors are each synthetic cables.

7. The conveyor corner according to any one of claims 1 to 6 wherein said ratio is substantially the same as the ratio of an upper pith length, from a first radius to a second radius from said centre of 4 t curvature followed by said outer flexible connector, to an upper path length, from said first radius to said second radius followed by said inner flexible connector. 1 "~Ti~ j ii 15

8. The conveyor corner according to any one of claims 1 to 7 wherein a drive means associated with said drive receiving means is located either on the same side of said curved pathway as said drive receiving means or on the other side of said curved pathway from said drive receiving means or said drive means originates from an adjacent conveyor connected in series with said conveying corner.

9. The conveyor corner according to any one of claims 1 to 8 wherein said drive receiving means comprises gear wheels with a gearing ratio in the same said ratio.

10. A conveyor corner substantially as herein described with reference to the accompanying drawings. ci a Ed 4 -W *l a *3: Dated: 24 September 1991 PHILLIPS ORMONDE FITZPATRICK Attorneys for: G.R. PATTON ENGINEERING, LTD. C I. C L OotAA, 46 inner wheel and said flexible connector further from said centre of curvature passing over each said outer wheel; and 16 ABSTRACT A conveyor corner comprising a frame which defines a curved pathway along which travels a conveyor comprising an endless succession of rollers Mounted on the frame at each end of the pathway is a pair of wheels 22) (24,26) over which passes endless flexible connectors (15,17). The connectors are connected to each end of each roller A means to drive the conveyor is connected to one pair of wheels (24, 26). The arrangement is such that all wheels in both pairs of wheels (20,22) (24,26) have the same diameter, the inner wheels (22,24) have more "teeth" than the outer wheels (20, 26) and the outer wheel (26) is independently ',riven at a faster speed than the inner wheel In motion the arrangement ensures that the rollers (10) maintain their same relative position to each other so that an article conveyed thereon travels smoothly around the corner. f ~fKS t C, 4 ip Af 9d t t t "e