US3841463A

US3841463A - Stacker conveyor with flexible section

Info

Publication number: US3841463A
Application number: US00387215A
Authority: US
Inventors: G Wicksall; G Stone; A Orloff
Original assignee: STONE CONVEYOR Inc
Current assignee: STONE CONVEYOR Inc
Priority date: 1971-09-01
Filing date: 1973-08-08
Publication date: 1974-10-15
Anticipated expiration: 1991-10-15

Abstract

A stacker conveyor assembly with a flexing section comprised of a stationary truss framework, a movable truss framework pivotally mounted relative to the stationary truss framework for movement in a vertical plane, and a flexible section extending between the stationary and movable truss frameworks for supporting a section of troughed conveyor belt which gently bends through an arc in a vertical plane of the truss frameworks. The ends of the flexible section are connected to the truss frameworks by way of sliding joints which permit longitudinal movement of the flexible section members relative to the truss frameworks, thereby permitting adjustment of the angle of inclination of the movable truss framework.

Description

Unite States Patent Stone et a1.

[ Oct. 15, 1974 [54] STACKER CONVEYOR WITH FLEXlIBLE 2,818,965 1/1958 Horth 198 109 SECTION [75] Inventors: Guthrie B. Stone, Honeoye; Arthur Primary EXamUYerTRChard Schacher Assistant Exammer-Joseph E. Valenza Orloff, Nunda, Guy J. Wlcksa1l, A A F Cl, A & Fayette, an of NY ttorney, gem, or zrmarence r1611- Harvey B. Jacobson [73] Assignee: Stone Conveyor, Inc., Honeoye,

57 ABSTRACT [22] led: 1973 A stacker conveyor assembly with a flexing section 21] L 337 215 comprised of a stationary truss framework, a movable truss framework pivotally mounted relative to the sta- Related Apphcatmn Dam tionary truss framework for movement in a vertical 1 Continuation of p I971, plane, and a flexible section extending between the abandoned stationary and movable truss frameworks for supporting a section of troughed conveyor belt which gently U-S. bends through an arc in a vertical plane of the truss 1 Clframeworks The ends of the flexible section are on. 1581 held of Search 198/1 1, 1091 l l 14, nected to the truss frameworks by way of sliding joints 198/115, 117, 121, 122, 233; 214/10 which permit longitudinal movement of the flexible section members relative to the truss frameworks, 1 1 References Clted thereby permitting adjustment of the angle of inclina- UNITED STATES PATENTS tion of the movable truss framework.

552,716 1/1896 Matthiessen 198/109 2,795,315 6/1957 Hahir et a1 198 109 9 Clams l3 Draw'ng guns D oio o l STACKER CONVEYOR WITH FLEXIBLE SECTION This is a continuation of application Ser. No. 176,902, filed Sept. 1, 197i, now abandoned.

The present invention is generally related to stacker conveyors, and, more particularly, to stacking conveyors used to form storage piles of materials such as gravel, sand, crushed stone, and coal. With many such materials, it is desirable to keep the discharge end of the conveyor close to the top of the storage pile to minimize the amount of dust generation, segregation and degradation of the materials.

Previously, this had been achieved with two types of elevating stacker conveyors. One such conventional stacker conveyor provided means for pivoting the entire conveyor about its loading end to provide vertical adjustment of the discharge end to maintain it in close proximity to the top of the storage pile. This type of construction, however, was found, for the most part, to be unacceptable for several reasons, one of which was the limited overall size and load-carrying capacity. Furthermore, the initial costs of such constructions was unusually high which was compounded by unusual maintenance and breakdown problems.

Another type of conventional elevating stacker conveyor was provided with a joint in its mid-section, making it necessary to move only a portion of the entire conveyor in an attempt to alleviate the problems of the aforementioned construction. Such two-piece conventional constructions, however, required that the trough in the conveyor belt be flattened at the joint to permit bending without developing excessive tension in the edge portions of the belt. This greatly limited the carrying capacity of the belt since the flat section at the joint could not carry nearly as much material as the troughed sections of conveyor belt.

It is an object of the present invention to provide a flexing stacker conveyor assembly having a troughed conveyor belt which is maintained in a troughed condition while passing through a flexing support frame, such that the discharge end of the conveyor may be adjusted to the proximity of the storage pile, yet the overall carrying capacity of the conveyor is not significantly reduced.

Another object of the present invention is to provide a stacker conveyor assembly comprised of a movable framework which is pivotally connected to a stationary conveyor framework with a flexible support frame extending therebetween which bends in a vertical plane to support a gently curved section of troughed conveyor belt.

It is a further object of the present invention to provide a versatile stacker conveyor assembly having a flexing framework which gently curves a section of troughed conveyor belt, such that one end of the conveyor may be moved up and down in the vertical plane to maintain close proximity to the storage piles of conveyed materials, thus minimizing the generation of dust, segregation and degradation of the materials.

Still another object of the present invention is to provide a novel flexible section for a stacker conveyor comprised of two pairs of elongated parallel bending members, the opposite ends of which are slidably connected between a stationary and a movable framework, such that the arc of the bending members may be varied to change the inclination of the movable truss framework, permitting the use of a troughed conveyor LII belt along the entire load carrying length of the conveyor assembly.

These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout, and in which:

FIG. 1 is an aerial view of a typical storage pile of material formed by the stacker conveyor assembly of the present invention;

FIG. 2 is a broken elevation of the stacker conveyor assembly in the raised position, with a phantom view of the movable truss framework in a lowered position;

FIG. 3 is a partial elevation of the flexing section with the truss framework partially removed;

FIG. 3A is an elevation illustrating the pivotal connection between the stationary and movable truss frameworks;

FIG. 4 is a geometric illustration of the flexing section of the stacker conveyor assembly, with movable framework in the raised and lowered positions;

FIG. 5 is a plan view of the bending members of the flexing section slidably supported between the movable and stationary truss frameworks;

FIG. 5A is a cross-sectional view of the sliding joint connecting the bending members with the truss frameworks;

FIG. 6 is a perspective view of a linkage mounting plate connected to the tubular members of the flexing station;

FIG. 7 is a perspective view of a flat mounting plate connected to the. tubular members of the flexing section;

FIG. 8 is a cross-sectional view of the flexing members connected to a trough roller support bracket by wayof the flat mounting plate shown in FIG. 7;

FIG. 9 is an end view of the stationary truss framework;

FIG. 10 is an end view of the movable truss framework; and

FIG. 11 is a sectional view of the fixed truss framework taken along section 11-11 with a conveyor hood added.

Referring, now, more particularly to FIGS. 1 and 2, the stacker conveyor assembly of the present invention is generally referred to by the numeral 20, and is adapted to form storage piles 22 of materials such as sand, gravel, crushed stone, and coal. The conveyor assembly includes a vertical support tower 24 which rests upon a mobile tractor unit 26, which is adapted to be driven or moved along a track or path 28 to provide an arcuate-shaped storage pile of material. The tractor and vertical support tower may be guided by a pair of horizontal cables 30 which are connected at one end to a rotatable rigid base 32 which serves to pivotally accommodate the loading end of the conveyor assembly.

It is appreciated, from the illustration of FIG. 2, that the conveyor assembly is comprised of a movable truss framework 34 which is pivotally mounted for movement between raised and lowered positions, such that the discharge end of the conveyor may be maintained in close proximity to the top of the material storage pile. This minimizes the generation of dust, and the segregation and degradation of the materials being conveyed to the storage pile. Thus, it can be seen that, not only can the stacker conveyor assembly of the present invention be articulated in a circular path, but also be raised and lowered to maintain the discharge end in close proximity to the top of the storage pile. This construction both minimizes the generation of dust, and

permits the formation of large storage piles of material with a single stacker conveyor assembly.

A stationary truss framework 36 extends between the pivot support 32 and the support tower 24 and is approximately one-half the total length of the over-all conveyor. A support arm 38 may be provided to stabilize the stationary truss framework relative to the support tower. A fixed guy wire 40 extends from the loading end of the stationary truss framework to the top area of the vertical support tower 24, and a movable pulley assembly 42 extends between the top of the supporttower to the movable truss framework 34 to affect movement between the raised and lowered positions. Pulley assembly 42 may be driven by conventional motors and winches not considered to be a part of the present invention and not illustrated in the drawings.

Referring to FIG. 3, a flexing section of the conveyor is generally referred to by the numeral 44 and includes a troughed conveyor belt 46 made of conventional flexible conveyor belt materials. A plurality of spaced trough roller assemblies 48 are provided to support the conveyor belt at points along its length, each assembly being connected to two pairs of tubular members 50 made of steel, or similar materials, and being of an elastic quality, such that they are bendable, yet resilient in nature to return to their original straight shape. At least one end of each tubular bending member 50 is journaled in a channel or collar 52, of similar crosssectional shape, to form a sliding joint with the stationary and movable truss frameworks respectively to allow for variation in length during bending, and to keep the ends parallel to the adjacent truss sections. The joints of conventional two-piece stacker conveyor constructions required that the conveyor belt be flattened within the area of the joint. This was required to prevent excessive tension in the outermost edge portions of the belt, due to the acuteness of the angle formed at the joint. With the flexing section of the present invention, however. the angle through which the conveyor must bend is extended, or spread out over a considerable arced length of conveyor belt. This is due to the length of the bending tubular members 50. Such an arrangement greatly reduces the tension in the outermost edge portions of the belt, thereby permitting the belt to be maintained in its original troughed shape, such that the load capacity of the belt is not reduced as with conventional constructions.

As the troughed conveyor belt moves in the direction of arrow 54, the materials carried thereby are ultimately unloaded at the end of the movable truss framework, and the belt assumes a flattened condition for return in the direction indicated by arrow 56. A plurality of return idler rollers 58 are provided in the stationary and movable truss frameworks. In addition, the belt travels around a main drive roll or spool 60 driven by a motor in a conventional manner, such that the belt is continuously advanced over the idler rollers and troughed roller assemblies by which a continuous flow of materials may be achieved.

Main idler rollers

62 and 63 are mounted onto the truss frameworks to feed and return the conveyor belt to and from a remote idler roller 64 connected to a weight box assembly 65, of a conventional type. It is apparent that as the movable truss framework is pivoted toward the raised position, the spacing between main idler roller 62 on movable framework 34 and remote idler roller 64 is slightly increased. At the same time, the length of conveyor belt traveling over the distance of the flexing section is somewhat reduced. Such changes in length are compensated for by the idler roller 64 and weight box assembly 65 which moves vertically to take up any slack in the belt and maintain constant belt tension. Thus, belt tension is unaffected, regardless of the vertical position of the stacker conveyor assembly.

The connection between the stationary and movable truss frameworks and the mast is best illustrated in FIG. 3A. It can be seen that a rigid I-beam 66 is welded to the mast to provide a support for a pair of mounting

plates

68 and 69. A pair of pins 70 extend through mounting holes in each

plate

68 and 69 and are journaled in collar openings in each of vthe truss frameworks. As such, the movable truss framework 34 is permitted to pivot in a vertical plane about mounting pins 70. This arrangement provides a rigid, durable, pivoting joint between the truss frameworks and mast.

It is essential to provide vertical support to the bending tubular members 50 to maintain a gently curving arc. A plurality of linkage members 72 are provided, each extending between the flexible members 50 and a corresponding connecting plate 74. A plurality of inclined linkage members 76 extend between the connection plates and the truss frameworks, and the connection plates are interconnected by way of a pair of horizontal linkage members 78. Each linkage member is pivotally fastened to the corresponding connection plate 74 to permit proper movement of the linkage members during corresponding movement of the truss framework. The geometry of the linkages is such that bendable tubular members 50 are supported by linkages 72 to form a smooth arc throughout the flexing section. The geometric relationship between the linkage members and the truss frameworks is best illustrated by FIG. 4. Not only are the bendable tubular members supported by the vertical linkage members, but, also, they are guided to form a gently curved path which is followed by the troughed section of conveyor belt.

Referring to FIG. 5, the slidable mounting arrangement of the flexing section can be seen in more detail. Each sliding joint assembly 52 is comprised of an elongated channel 80 which is of a width slightly greater than the composite width of a corresponding pair of flexible tubular members 50, such that the ends of the tubular members extend into the channel supports 80, for sliding engagement therewith. In order to prevent dislodgment of the tubular members during bending, and in order to provide easy mounting and removal of the tubular members from the channel supports 80, a U-shaped mounting bracket 82 is provided which fits within the opening of each channel support 80 and is held in position by a pair of bolts 84.

The geometry of the flexible section 50, the controlling linkage, and the pivot of the movable truss section is such that there isonly a slight movement of the flexible section in the sliding joint assemblies 52, and the position of the flexible section in the sliding joint assemblies is the same at the extreme positions. The distance between the sliding joints measured along the flexible section is a minimum at the raised and lowered positions of the movable truss section, and increases slightly at intermediate positions, reaching a maximum near the center of travel of the movable truss. This particular geometry permits the use of sliding joints of minimum length.

Transverse support between the parallel pairs of tubular members is provided by a plurality of lateral supports 86, the ends of which are welded to the corresponding tubular members. These weld joints, preferably, are made in the proximity of the attachment of each trough roller assembly 48, as shown in FIG. 8. Each trough roller assembly is held in position by way of a bolt 88 extending downwardly through the space separating each pair of tubular members 50 and through a flat mounting plate 90 welded to the tubular members.

FIGS. 6 and 7 illustrate the two types of mounting plates or brackets which are welded to the tubular members 50. FIG. 6 shows a linkage member mounting bracket 92 which is adapted to accept the upper ends of vertical linkage members 72 shown in FIG. 3, by way of downwardly extending tab portions 94. Apertures 96 are adapted to accommodate bolts which fasten the trough roller assemblies to the tubular members in a fashion similar to that illustrated in FIG. 8. FIG. 7 shows the flat mounting plate 90 in more detail, the plate being provided with an aperture 96 adapted to accept the bolt arrangement illustrated in FlG. 8.

Looking to FIG. 11, it can be seen that the stacker conveyor assembly of the present invention may be provided with a hood attachment 100 which is adapted to cover the troughed conveyor belt to protect the material against the elements. It can also be seen that each trough roller assembly 48 may be comprised of three rollers, a horizontal roller 102, and a pair of oppositely disposed and oppositely inclined rollers 104 and 106 respectively.

FIG. 9 is an end view of the stationary truss framework and illustrates the relative position of

idler rollers

58 and 63. Also, the relative positions of the sliding joints 52 are shown in more detail. Similarly, FIG. 10 is an end view of the movable truss framework, with the relative positions of

idler rollers

58 and 62 as well as sliding joints 52 being shown in more detail.

It is apparent from the foregoing description that the stacker conveyor assembly of the present invention provides a means for adjusting the vertical position of the discharge end of the conveyor, yet permitting the use of a troughed conveyor belt throughout the entire length which the material is carried by'the conveyor. This provides for maximum carrying capacity of the conveyor belt and at the same time requires movement of only a portion of the over-all conveyor assembly. Such a stacker conveyor assembly is relatively less expensive to produce compared to conventional constructions of comparable load carrying capacity. Furthermore, the conveyor assembly of the present invention requires less framework moving equipment for articulation of the movable truss framework which not only reduces the initial cost, but also, the maintenance costs over a period of time. Changes in shape or materi als of the troughed conveyor belt, the troughed roller assemblies or other components of the stacker conveyor assembly are deemed to fall within the scope of the present invention.

The foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly all suitable modifications and equivalents may be resorted to, falling within the scope of the invention.

What is claimed as new is as follows:

1. A conveyor assembly, said assembly comprising a stationary truss, a movable truss, mounting means pivotally supporting one end of said movable truss adjacent a first end of said stationary truss with said trusses disposed in closely adjacent end-to-end relation in generally the same plane and the other end of said movable truss swingable in said plane, an elongated, stiff but flexible and resilient support structure generally paralleling said plane and positioned with its opposite ends overlapping the adjacent ends of said trusses, first support means supporting the opposite ends of said resilient support structure from remote portions of said trusses spaced therealong from the adjacent ends of said trusses and with said opposite ends generally paralleling the corresponding truss portions and supported therefrom for limited lengthwise guided shifting longitudinally therealong, second support means connected to and supported at least in part from said trusses and supportingly engaged with predetermined portions of said resilient support structure disposed at a plurality of points spaced apart therealong between and from said opposite ends and operative, in response to relative angular displacement of said trusses, to support and automatically shift said spaced predetermined portions of said support structure to predetermined positions along a substantially constant radius path containing the opposite ends of said support structure during angular displacement of said movable truss relative to said stationary truss, and conveyor belt support means supported from and closely spaced along said resilient support structure and the remote end portions of said trusses on the remote sides of said first support means for supporting a flexible conveyor belt in a path substantially paralleling the remote end portions of said trusses and said resilient support structure in order that the path of that portion of the supported conveyor belt extending between said remote end portions of said trusses will comprise a substantially constant radius arc whose opposite ends merge smoothly into the portions of the conveyor belt supported from said remote end portions.

2. The combination of claim 1 wherein said trusses each include opposite side longitudinal members, said resilient structure including a pair of spaced side-byside elongated, stiff but flexible and resilient members, said resilient members each being positioned with their opposite ends overlapping the adjacent ends of one pair of corresponding side longitudinal members and supported therefrom by said first support means.

3. The combination of claim 2 wherein said elongated support structure includes rigid transverse support members extending between and rigidly interconnecting corresponding portions of said resilient memand parallel resilient structural members rigidly interconnected at a plurality of points spaced therealong.

5. The combination of claim 3 wherein said conveyor belt support means includes a plurality of belt craddling structures extending between and rigidly connected to said resilient members at points spaced therealong.

6. The combination of claim 1 wherein said trusses each include opposite side longitudinal members, said resilient support structure including a pair of spaced side-by-side elongated, stiff but flexible and resilient members, said resilient members each being positioned with their opposite ends overlapping the adjacent ends of one pair of corresponding side longitudinal members and supported therefrom by said first support means, said first support means comprising a sleeve member supported from and extending along each opposite side longitudinal member, the opposite ends of said resilient members being slidingly telescoped in a corresponding sleeve member.

7. The combination of claim 1 including an upstanding support tower, said first end of said stationary truss being supported from an upper portion of said support tower, said upper portion of said support tower comprising said mounting means for said one end of said movable truss.

8. The combination of claim 7 including means connected between said tower and the other end of said movable truss for supporting the latter in adjusted angularly displaced positions relative to said stationary truss.

9. The combination of claim 1 including a stationary base, said stationary truss being inclined with said first end thereof uppermost, means supporting the second end of said stationary truss from said base for angular displacement about an upstanding axis, the lower end of said tower including a mobile support unit adapted to move in an arcuate path disposed in a plane normal to said upstanding axis and having the latter as its center of curvature.

Claims

2. The combination of claim 1 wherein said trusses each include opposite side longitudinal members, said resilient structure including a pair of spaced side-by-side elongated, stiff but flexible and resilient members, said resilient members each being positioned with their opposite ends overlapping the adjacent ends of one pair of corresponding side longitudinal members and supported therefrom by said first support means.

3. The combination of claim 2 wherein said elongated support structure includes rigid transverse support members extending between and rigidly interconnecting corresponding portions of said resilient members defining said predetermined portions of said resilient support structure.

4. The combination of claim 3 wherein each of said resilient members comprises a pair of elongated spaced and parallel resilient structural members rigidly interconnected at a plurality of points spaced therealong.