# Patent

## Title
Methods of magnetic conveyor support

## Abstract

Apparatuses designed to provide support to a conveyor belt in a new manner. In a first illustrative embodiment, a conveyor belt is supported by a number of magnets. A first set of magnets are disposed on the edges of the conveyor belt, and a second set of magnets are disposed on a support apparatus for the conveyor belt. The first and second sets of magnets interact to create repulsive forces that provide both lateral and vertical support to the conveyor belt. Tension provided by the lateral forces can help the belt move smoothly and with less wear than the support provided by existing support idlers.

## Background
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a continuation of co-pending U.S. application Ser. No. 11/616,752, filed Dec. 27, 2006; which is a continuation of U.S. application Ser. No. 11/263,690, filed Nov. 1, 2005, now U.S. Pat. No. 7,159,708; which is a divisional of U.S. application Ser. No. 10/732,718, filed Dec. 10, 2003, now U.S. Pat. No. 6,971,507; the entire disclosures of which are incorporated herein by reference.


FIELD
The present invention is related to the field of materials conveyance. More particularly, the present invention relates to the field of conveyer devices.
BACKGROUND
Conveyor belts are used to move materials in a wide variety of industries and environments. Some such conveyor belts are used, for example, in moving ore within a mine, gravel or rocks within a quarry, and in a variety of industrial applications where bulk materials are moved.
FIG. 1 illustrates a prior art conveyor. The conveyor includes a conveyor framework 2 which may be made, for example, using channel, angle-iron, trusswork, or a variety of other configurations. A conveyor belt 4 is supported by support idler frames 6 which include a number of support idler rollers 8. Driving force may be applied by any number of methods/apparatuses, including, for example, creating a turning force at the rollers shown on the end of the framework 2, or by application of force using magnets on the conveyor belt 4 itself which interact with stators placed relative the edges of the conveyor belt 4.
FIG. 2 shows a closer, cut-away view of a prior art conveyor, highlighting the conveyor belt 4, idler support 6, and idler rollers 8. As shown, the idler rollers 8 are angled with respect to one another such that the conveyor belt 4 forms a trough in which a material to be conveyed rests during transport. The idler supports 6 are secured relative the conveyor framework 2. There is a slight sag between the rollers 8, and it can be seen that the conveyor belt 4 does not pass smoothly over the rollers 8, instead being shaped thereby with slight angular form.
The conveyor belt 4 is typically constructed as a relatively flat, flexible member having a first end and a second end, where the ends are secured together to create a loop by the use of a securing apparatus. In a simplest form, the conveyor belt 4 has two ends coupled together by interacting teeth or interleaved loops, where a wire, for example, is passed through the interleaved loops to secure the first end of the conveyor belt 4 to the second end of the conveyor belt 4. Other forms, such as vulcanized “endless” belts may also be used. Any number of individual sections may be pieced together in this or another suitable manner to build the conveyor belt 4.
One of the limitations of such prior art conveyor support designs is that the supportive force of the rollers 8 causes localized strain on the conveyor belt 4, wearing the conveyor belt 4. Further, the rollers 8 are subject to wear and degradation, and require periodic replacement. The rollers 8 include internal bearings that occasionally wear out, and with the large number of moving parts, the overall system is subject to failure in harsh environments.
SUMMARY
The present invention, in an illustrative embodiment, includes apparatuses designed to provide support to a conveyor belt in a new manner. In a first illustrative embodiment, a conveyor belt is supported by a number of magnets. A first set of magnets are disposed on the edges of the conveyor belt, and a second set of magnets are disposed on a support apparatus for the conveyor belt. The first and second sets of magnets interact to create repulsive forces that provide both lateral and vertical force to the conveyor belt.



BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of an illustrative prior art conveyor;
FIG. 2 is a cutaway view highlighting a portion of the illustrative prior art conveyor of FIG. 1;
FIG. 3 is a perspective view of a first embodiment of a magnetically supported conveyor system;
FIG. 4 is a section view of an illustrative embodiment showing greater detail of the supporting framework for a magnetically supported conveyor system;
FIG. 5 is a cross-sectional view of an illustrative support framework;
FIG. 6 is a cross-sectional view of another illustrative support framework;
FIG. 7 is a cross-sectional view of yet another illustrative support framework;
FIG. 8 illustrates in detail a magnetic layout for a magnetically supported conveyor system;
FIG. 9 illustrates in detail another magnetic layout for a magnetically supported conveyor system;
FIG. 10 illustrates a rectangular magnetic layout for a magnetically supported conveyor system;
FIG. 11 shows, in side view, a portion of a magnetically supported conveyor system;
FIG. 12 is a cross-sectional view of another illustrative support framework; and
FIG. 13 is a side view of another illustrative conveyor system.



DETAILED DESCRIPTION
The following detailed description should be read with reference to the drawings. The drawings, which are not necessarily to scale, depict illustrative embodiments and are not intended to limit the scope of the invention.
FIG. 3 is a perspective view of a first embodiment of a magnetically supported conveyor system. The system includes a conveyor framework 52 that is used with a conveyor belt 54. The system includes tension members 60 and several support arms 62 that are secured to the conveyor framework 52 by several support pivot mounts 64. Several upper pivot mounts 66 are also included.
The conveyor belt 54 is at least partly supported by the use of magnetic forces. In particular, a number of outer magnet housings 70 are secured to the conveyor belt 54. The conveyor belt 54 is then suspended between two inner magnet housings 72. As illustrated in greater detail below, the outer magnet housings 70 and inner magnet housings 72 interact magnetically. Repulsive forces between the outer magnet housings 70 and inner magnet housings 72 support the conveyor belt 54.
FIG. 4 is a section view of an illustrative embodiment showing greater detail of the supporting framework for a magnetically supported conveyor system. The conveyor framework 52 is secured by a lower pivot mount 68 to the tension member 60, which is in turn secured to the support arm 62 by the upper pivot mount 66. The support arm 62 is also secured to the conveyor framework by support pivot mounts 64.
As can be seen, the outer magnet housings 70 wrap around the inner magnet housing 72 so that both lateral and vertical support is provided to the conveyor belt 54. The conveyor belt 54 is held in position under lateral tension. The weight of whatever material is carried the conveyor belt 54 will cause the conveyor belt 54 to sag in the middle. As the conveyor belt 54 sags, more material can be carried by the conveyor up to a point, however, too much sag can reduce capacity and cause excessive wear on the conveyor belt 54. To prevent too much sag from occurring, tension members 60 are provided between the support arms 62. If the conveyor belt 54 is empty, less wear on the conveyor belt 54 occurs when it runs flat, so the tension members 60 are also adapted to cause the conveyor belt 54 to run flat when empty, yet allow some sag to occur as the conveyor belt 54 is loaded. The tension members 60 may include a stop preventing too much sag from occurring, for example, to keep the conveyor belt 54 from coming into contact with the tension members 60. If desired or necessary, additional support devices may be used in conjunction with the magnetic support provided by the magnet housings 70, 72. The several pivot mounts 64, 66, 68 allow the conveyor belt 54 to go from a sagging configuration to a flat position (and the reverse) smoothly and easily.
FIG. 5 is a cross-sectional view of an illustrative support framework. The cross section shows how the tension members 60 cross from the lower pivot mounts 68 to the upper pivot mounts 66 to provide lateral support to the support arms 62. The support pivot mounts 64 allow the support arms 62 to move with respect to the conveyor framework 52, allowing the conveyor belt 54 to have lateral flexibility.
Also illustrated is how the outer magnet housing 70 at least partly surrounds the inner magnet housing 72. The outer magnet housing 70 contains outer magnets 76, which interact with inner magnets 74 contained by the inner magnet housing 72. The outer magnets 76 are all aligned in similar polarity, as are the inner magnets 74, such that the outer magnets 76 collectively repel the inner magnets 74. The conveyor belt 54 thus moves on a cushion of air with decreased wear and friction.
While the preferred embodiments of the present invention include magnets 74, 76 that create a cushion of air between the inner and outer housings, other configurations are also contemplated. For example, frictional contact between the inner and outer housings may be allowed in some embodiments. If desired a lubricant (wet or dry) may be provided between the inner and outer housings to make movement with contact easier.
Additionally, the magnets 74, 76 may provide primary or supplemental support to a conveyor belt. For example, if desired, the magnets 74, 76 may be sufficient to provide guiding forces to a belt, wherein the magnets 74, 76 and tension members 60 are sufficient to keep the belt relatively flat while the belt is running empty, but when the belt is loaded the belt is allowed to deform and move generally as shown in FIG. 1, with rollers disposed longitudinally between the tension members. By allowing the belt to run relatively flat while unloaded, friction and wear are reduced, while rollers may be provided to give additional support when the belt is heavily loaded.
In several embodiments additional support devices may be provided as well. For example, an impact cradle or bed such as an impact slider bed may be provided beneath the belt 54 at a location corresponding to a hopper or loading area. The impact slider bed may include, for example, a slippery hard plastic upper layer over a cushioned layer. One example impact slider bed includes a number of elongate members that run longitudinally beneath a portion of the belt 54, each elongate member having at least two layers, with the upper layer being a slippery plastic about 1⁄3 the thickness of the member, and a lower layer made up of a relatively soft, cushioning rubber that covers approximately 2⁄3 of the thickness of the member. If desired, a spring or rigid support, such as a piece of iron or steel, may hold up the elongate members.
FIG. 6 is a cross-sectional view of another illustrative support framework. Again, the tension members 60 are coupled to the support legs 62 and conveyor framework 52 using upper and lower pivot mounts 66, 68. The support legs 62 themselves are coupled to the conveyor framework by the support pivot mounts 64. The main difference from FIG. 5 to FIG. 6 is in the shape of the outer magnet housing 70′ and inner magnet housing 72′. Rather than a curved shape (as shown by the magnet housings 70, 72 in FIG. 5), the magnet housings 70′, 72′ in FIG. 6 are rectangular. By using the rectangular shape, the inner magnets 74′ may be disposed differently, for example, the upper magnet of the inner magnets 74′ may have a N/S polarity where the N pole is up, and the lower magnet may have the same alignment, so that the upper and lower magnets of the inner magnet attract one another and hold each other in place, yet repel the outer magnets 76′.
FIG. 7 is a cross-sectional view of yet another illustrative support framework. A conveyor framework 152 is used to support a conveyor belt 154 as follows. Support arms 162 are secured to the conveyor framework by support pivot mounts 164. A tension member 160 is coupled to the support arms 162 using arm pivot mounts 166. The tension member 160 is configured to push the support arms 162 apart, keeping the conveyor belt 154 under tension. The tension member 160 configured as shown simplifies the overall design, however, as illustrated, the conveyor belt 154 is not allowed to sag as far as it otherwise might, since the tension member 160 is in the way.
The conveyor belt 154 is coupled to the support arms 162 by the use of an outer magnet housing 170 that is disposed about an inner magnet housing 172. The repulsive magnetic forces between the inner magnets 174 and outer magnets 176 creates an air gap that allows the conveyor belt 154 to move without significant friction caused either by support along its edges or friction creating by passage over idler rollers.
FIG. 8 illustrates in detail a magnetic layout for a magnetically supported conveyor system. The configuration corresponds to that illustrated in FIG. 5. The tension member 60 pushes the arm 62 outward through its connection to the upper pivot mount 66. In turn, the arm transmits both vertical and lateral forces to the inner magnet housing 72 containing a number of inner magnets 74. Preferably, each of the inner magnets 74 is orientated with the same field polarity facing outside. The outer magnet housing 70 contains several outer magnets 76, which preferably are orientated to each have the same field polarity facing inside. The field polarity facing inside for the outer magnets 76 is preferably the same as the field polarity facing outside for the inner magnets 74, such that the outer magnets 76 and inner magnets 74 repel one another.
FIG. 9 illustrates in detail another magnetic layout for a magnetically supported conveyor system. The inner magnets 74 comprise a single magnet, and the outer magnets 76 are also a single magnet. If desired, one or both of the magnets may be an electro-magnet that is coupled to a source of electricity such that, when the electricity is on, the magnetic field generated by at least one of the magnets 74, 76 is boosted. Then, if desired, the electricity could be cut off when the belt 54 is not moving, reducing the resting tension on the belt 54.
FIG. 10 illustrates a rectangular magnetic layout for a magnetically supported conveyor system. The outer magnet housing 70′ is shaped to preserve an air cushion around the inner magnet housing 72′. The inner magnets 74′ are oriented and disposed to provide a repulsive force with respect to the outer magnets 76′.
FIG. 11 shows, in side view, a portion of a magnetically supported conveyor system. The system may include a number of outer housing structures 70 disposed about an inner housing structure 72 to support the conveyor belt 54. The conveyor belt 54 is supported over a conveyor framework 52 by the use of several support arms 62 that may be spaced or alternated as shown. The support arms 62 are secured between the conveyor framework 52 and the conveyor belt 54 by support pivot mounts 64. Tension members 60 may attach to the support arms 62 as noted above.
The conveyor belt 54 may be motivated by any suitable mechanism or device. Pulley and/or roller systems, along with geared devices having teeth that engage the conveyor belt 54 may be used. Several magnet and stator systems may also be used, for example.
FIG. 12 is a cross-sectional view of another illustrative support framework. The support framework supports a conveyor belt 100 using outer magnetic housings 102 and inner magnetic housings 104. The housings 102, 104 may be as outlined above. The support arms 106 are tensioned, laterally, by a tension member 108. Rather than two side-by-side frame members having a number of cross members therebetween (such a support framework would be used with several of the above embodiments), the illustrative framework in FIG. 12 makes use of a single central member 110. Because the support arms 106 angle outward with respect to the central member 110, the force of gravity creates tension across the conveyor belt 100. As such the conveyor belt 100 tends to run flat when unloaded.
The tension member 108 may provide pushing forces between the support arms 106 when the conveyor belt 100 is heavily loaded. For example, if the conveyor belt 100 is heavily loaded, troughing in the middle will tend to pull the support arms 106 together, so the tension member 108 may provide a pushing force to prevent over-troughing of the conveyor belt 100.
FIG. 13 is a side view of another illustrative conveyor system. The system is similar to that shown in FIG. 11, with a first magnetic support structure shown generally at 150 for belt 152, and a second magnetic support structure shown generally at 154. Between the magnetic support structures is a roller-type structure, as shown generally at 156.
Those skilled in the art will recognize that the present invention may be manifested in a variety of forms other than the specific embodiments described and contemplated herein. Accordingly, departures in form and detail may be made without departing from the scope and spirit of the present invention as described in the appended claims.

## Claims

1. A material conveyance apparatus comprising:
a belt extending in a longitudinal direction, the belt having a first side edge including one or more magnets and a second side edge including one or more magnets;
a framework for supporting the belt, the framework including:
a central member extending in the longitudinal direction;
a first support arm extending outward from the central member toward the first side edge of the belt; and
a second support arm extending outward from the central member toward the second side edge of the belt;

wherein the one or more magnets of the first side edge provide a repulsive force repelling the first side edge away from the first support arm; and
wherein the one or more magnets of the second side edge provide a repulsive force repelling the second side edge away from the second support arm.

2. The material conveyance apparatus of claim 1, wherein a lateral direction is defined between the first side edge and the second side edge of the belt, wherein the repulsive force provided by the one or more magnets of the first side edge includes a component in the lateral direction.

3. The material conveyance apparatus of claim 2, wherein the repulsive force provided by the one or more magnets of the second side edge includes a component in the lateral direction opposite that provided by the one or more magnets of the first side edge.

4. The material conveyance apparatus of claim 1, wherein the framework further comprises a tension member extending between the first support arm and the second support arm, wherein the tension member provides pushing forces between the first support arm and the second support arm in order to place lateral tension on the belt.

5. The material conveyance apparatus of claim 1, wherein the first support arm is pivotable relative to the central member.

6. The material conveyance apparatus of claim 5, wherein the framework further comprises a tension member extending between the first support arm and the second support arm, wherein the tension member pushes the first support arm away from the second support arm.

7. The material conveyance apparatus of claim 5, wherein the second support arm is pivotable relative to the central member.

8. The material conveyance apparatus of claim 7, wherein the framework further comprises a tension member extending between the first support arm and the second support arm, wherein the tension member pushes the first support arm away from the second support arm.

9. A material conveyance apparatus comprising:
a belt extending in a longitudinal direction, the belt having a first side edge including one or more magnets and a second side edge including one or more magnets;
a framework for supporting the belt, the framework including:
a first elongate support rail extending in the longitudinal direction adjacent the first side edge of the belt; and
a second elongate support rail extending in the longitudinal direction adjacent the second side edge of the belt;

wherein the one or more magnets of the first side edge provide a repulsive force repelling the first side edge away from the first elongate support rail and provide both vertical and lateral support to the belt; and
wherein the one or more magnets of the second side edge provide a repulsive force repelling the second side edge away from the second elongate support rail and provide both vertical and lateral support to the belt.

10. The material conveyance apparatus of claim 9, wherein the first elongate support rail includes one or more magnets, wherein the one or more magnets of the first elongate support rail repel the one or more magnets of the first side edge of the belt away from the first elongate support rail.

11. The material conveyance apparatus of claim 10, wherein the second elongate support rail includes one or more magnets, wherein the one or more magnets of the second support rail repel the one or more magnets of the second side edge of the belt away from the second elongate support rail.

12. The material conveyance apparatus of claim 9, wherein the framework further includes a first support arm pivotably coupled to the first support rail and a second support arm pivotably coupled to the second support rail.

13. The material conveyance apparatus of claim 12, further comprising a first tension member coupled to the first support arm, the first tension member pushing the first support rail away from the second support rail to keep the belt in tension.

14. The material conveyance apparatus of claim 13, further comprising a second tension member coupled to the second support arm, the second tension member pushing the second support rail away from the first support rail to keep the belt in tension.

15. A method of supporting a belt of a conveyance apparatus, the method comprising:
providing a belt having one or more magnets along a first edge of the belt and one or more magnets along a second edge of the belt;
providing a framework including a first support rail extending parallel to the first edge of the belt and a second support rail extending parallel to the second edge of the belt;
repelling the one or more magnets along the first edge of the belt away from the first support rail both laterally and vertically, forming a gap between the first support rail and the one or more magnets along the first edge of the belt; and
repelling the one or more magnets along the second edge of the belt away from the second support rail both laterally and vertically, forming a gap between the second support rail and the one or more magnets along the second edge of the belt;
thereby providing both lateral and vertical support to the belt.

16. The method of claim 15, wherein the first support rail includes one or more magnets, wherein the one or more magnets along the first edge of the belt are adapted to repel away from the one or more magnets of the first support rail.

17. The method of claim 16, wherein the second support rail includes one or more magnets, wherein the one or more magnets along the second edge of the belt are adapted to repel away from the one or more magnets of the second support rail.

18. A method of supporting a belt of a conveyance apparatus, the method comprising:
providing a belt having a first edge and a second edge, wherein a lateral direction is defined between the first side edge and the second side edge of the belt;
providing one or more magnets along the first edge of the belt and one or more magnets along the second edge of the belt;
providing a framework including a first support rail and a second support rail positioned parallel to the first support rail and spaced from the first support rail by a distance,
positioning the belt between the first support rail and the second support rail such that the first edge of the belt is parallel with the first support rail and the second edge of the belt is parallel with the second support rail, wherein the lateral direction of the belt spans between the first support rail and the second support rail;
repelling the one or more magnets along the first edge of the belt away from the first support rail, forming a gap between the first support rail and the one or more magnets along the first edge of the belt; and
repelling the one or more magnets along the second edge of the belt away from the second support rail, forming a gap between the second support rail and the one or more magnets along the second edge of the belt; and
varying the distance between the first support rail and the second support rail to vary the tension of the belt.

19. The method of claim 18, wherein the framework further includes a first support arm coupled to the first support rail, and a second support arm coupled to the second support rail, wherein the step of varying the distance between the first support rail and the second support rail includes moving the first support arm relative to the second support arm.

20. The method of claim 19, further comprising a tensioning member coupled to the first support arm to control the tension of the belt.

21. The method of claim 18, wherein the one or more magnets along the first edge of the belt are repelled away from the first support rail in both lateral and vertical directions.

22. The method of claim 21, wherein the one or more magnets along the second edge of the belt are repelled away from the first support rail in both lateral and vertical directions.