Patent Description:
As shown in <FIG>, a spiral overlay or mesh overlay conveyor belt <NUM> is comprised of wire spirals <NUM> intermeshed together by connecting rods <NUM> extending across the conveyor belt in the transverse direction. The ends of the rods extend through links <NUM> which pivotally connect adjacent rods, and are arranged along the side edges of the conveyor. The links also serve as tractive links in that they engage the sprockets which drive the conveyor.

Fatigue failure on the positively driven edge of the mesh overlay belt has been a concern in the past, as well as maintaining the belt in the proper position on the spiral conveyor.

Accordingly, there exists a need in the marketplace for a conveyor belt having an edge configuration for maintaining belt orientation, providing improved positive edge drive capability, and reducing fatigue failures on the driven edges of the conveyor belt. <CIT> discloses a conveyor belt according to the preamble of claim <NUM>.

A conveyor belt comprising a plurality of spaced tractive rods; a plurality of rows transversely disposed with respect to a direction of travel and interconnecting said plurality of spaced tractive rods; a plurality of belt drive clips; and wherein each of said rows comprises a U-shaped link on each edge and a mesh overlay extending therebetween. According to a further aspect of the disclosure, at least some of the U-shaped links include an integral hold-down clip; wherein said conveyor belt includes opposing first and second outer edges and said plurality of belt drive clips and/or U-shaped links with the integral hold-down clip are disposed on at least one of the first and second outer edges of the conveyor belt.

A conveyor belt with improved edge drive capability, said conveyor belt comprising a plurality of spaced tractive rods; a plurality of pitch rows transversely disposed with respect to a direction of travel and interconnecting said plurality of spaced tractive rods; and a plurality of belt drive clips; wherein each of said rows comprises a U-shaped link on each edge and a mesh overlay extending therebetween; wherein at least some of the U-shaped links include an edge guard; and wherein said conveyor belt includes opposing first and second outer edges and said plurality of belt drive clips and/or U-shaped links with the integral hold-down clip are disposed on at least one of the first and second outer edges of the conveyor belt. The invention is defined by the conveyor belt according to claim <NUM>.

These and other objects, features, and advantages of the invention will become more readily apparent to those skilled in the art upon reading the following detailed description, in conjunction with the appended drawings in which:.

An edge drive mesh overlay conveyor belt will be described below by reference to the embodiments disclosed here as examples and in accordance with the attached drawings. In the following descriptions of the various embodiments disclosed herein, it is understood that like reference numerals are used to describe the same elements throughout.

A conveyor belt <NUM>, <NUM> constructed using a plurality of belt drive clips <NUM> and a plurality of hold-down clips <NUM>, is shown in <FIG>. The belt drive clips <NUM> are preferably formed in a J-shape on every pitch, or support row, and a hold-down clip <NUM> is preferably positioned every third pitch, or support row, in an overlapping pattern. Other patterns such as every pitch, every other pitch, etc., could also be used. A standard reinforcing bar <NUM>, or a plurality of bars, may also be inserted into the belt <NUM> on those pitches, or support row, where no hold-down clip <NUM> is used.

The belt drive clip <NUM> and the hold-down clip <NUM> are fully disclosed in <CIT> to the present assignee.

A conveyor belt in accordance with a first embodiment of the disclosure here is shown generally in <FIG> by reference numeral <NUM>. Conveyor belt <NUM> preferably comprises a mesh overlay conveyor belt, although other belt types and configurations could of course be used. Conveyor belt <NUM> includes a plurality of spaced tractive rods <NUM> disposed in succession and transversely with respect to a direction of travel T as represented by arrow T of belt <NUM>, each rod <NUM> having two ends, each preferably terminating in a buttonhead <NUM>.

Belt <NUM> includes a plurality of support rows <NUM> transversely disposed with respect to the direction of travel T, and interconnecting the succession of rods <NUM>. Each row <NUM> is comprised of a plurality of U-shaped links <NUM>, each link connecting a rod <NUM> with a following rod in the succession. More preferably, each row <NUM> includes at least one link <NUM> on each end and a mesh overlay <NUM> extending therebetween. In addition, belt <NUM> preferably includes one or more rows including a J-shaped belt drive clip <NUM>, a hold-down clip <NUM> and a reinforcing bar <NUM> disposed along at least one edge of the conveyor belt. Belt drive clips <NUM>, hold-down clips <NUM> and reinforcing bars <NUM> can be positioned along both edges of the conveyor belt (as shown in <FIG>) depending on the desired construction and function of the particular belt. Still further, while the combined use of belt drive clips <NUM> and hold-down clips <NUM> is preferable, it is within the scope of the present disclosure that either one could be used by itself in connection with the conveyor belt. That is, the conveyor belt <NUM> may include only belt drive clips <NUM> and reinforcing bars <NUM> or, alternatively, only hold-down clips <NUM> and reinforcing bars <NUM>. As shown in <FIG>, belt <NUM> includes hold-down clips <NUM> along one edge (interior edge) and belt drive clips <NUM> and hold-down clips <NUM> along the other edge (exterior edge). Still further, belt <NUM>, <NUM> may be manufactured without any reinforcing bars or alternatively, several rows of reinforcing bars may be provided, depending upon the particular application. Thus, it should be apparent to one skilled in the art, that in accordance with the disclosure herein any combination of belt drive clips, hold-down clips and/or reinforcing bars may be used depending upon the particular application for which the conveyor belt is intended.

The combination of overlapping J-shaped drive clips and hold-down clips on the outer edge(s) of the conveyor belt with a welded U-shaped link and rod assembly provide support for the position of the metal mesh overlay. The rows of clips and bars along the outer, tension-bearing belt edge provide superior strength to offset the belt tension that results during system operation. The welded assembly of inner and outer U-shaped links and rods provides a structure that eliminates the possibility for excess lateral movement of the rows of bars and links from the inside or outside belt edges while at the same time provides surfaces where the belt can contact the stationary support rails (described further below). It is preferred for the U-shaped links to contact the support rails rather than the mesh overlay in order to reduce the contact pressure between the belt and rail, reducing also the likelihood of component wear.

As illustrated in <FIG>, the belt is driven forward by the engagement with sprockets positioned along the outer periphery of the belt's spiral path. If needed, the belt can also be driven from the top side or underneath using different sprockets to engage the U-shaped links along the belt edges. The J-shaped drive clips <NUM> are engaged by sprocket <NUM> driven by a vertically-oriented shaft of a spindle drive (not shown), while the hold-down clips <NUM> serve to maintain the belt <NUM>, <NUM> in proper orientation both laterally and vertically relative to the sprocket <NUM>. A vertical extension portion of the hold-down clip <NUM> supports the reaction loading on the belt <NUM> as a result of engagement with a support rail <NUM> (<FIG>). The upstanding member <NUM> of the hold-down clip <NUM> as it extends below the thickness of the belt <NUM> is typically positioned against a stationary support rail <NUM> and prevents the belt <NUM> from inadvertently lifting off of the support rail <NUM>. The opposing wings <NUM> on each side of the hold-down clip <NUM> are provided to ensure a smooth engagement with the rail <NUM> regardless of the driven direction of the belt <NUM>. Both the belt drive clip <NUM> and the hold-down clip <NUM> are positioned in an overlapping pattern along with additional reinforcing bars <NUM> to act as load carrying members, especially during those times when the belt <NUM> is partially collapsed, as in a turn for example.

A conveyor belt in accordance with a further exemplary embodiment which is not part of the invention
is shown generally in <FIG> by reference numeral <NUM>. Conveyor belt <NUM> preferably comprises a mesh overlay conveyor belt as described above, although other belt types and configurations could of course be used. Conveyor belt <NUM> includes a plurality of spaced tractive rods <NUM> disposed in succession and transversely with respect to a direction of travel of belt <NUM>, each rod <NUM> having two ends preferably terminating in a buttonhead <NUM>.

Belt <NUM> includes a plurality of support rows <NUM> transversely disposed with respect to the direction of travel T, and interconnecting the succession of rods <NUM>. Belt <NUM> preferably includes at least one row of J-shaped belt drive clips <NUM> disposed along at least one edge of the conveyor belt. Each row <NUM> is comprised of a plurality of links <NUM>, each link connecting a rod <NUM> with a following rod in the succession. More preferably, each pitch or row <NUM> includes at least one link <NUM> on each end and a mesh overlay <NUM> preferably extending therebetween. Link <NUM> includes an integral hold-down clip <NUM> comprising a depending extension <NUM> and an upstanding tab member <NUM>. The depending extension <NUM> supports the reaction loading on the belt <NUM> as a result of engagement with the support rail <NUM>. The upstanding tab member <NUM> of the integral hold-down clip <NUM> extends below the thickness of the belt <NUM> and would positioned against a stationary support rail <NUM> (as shown in <FIG>) and prevents the belt <NUM> from inadvertently lifting off of the support rail <NUM>.

In a further exemplary embodiment which is not part of the invention shown in <FIG>, at least one row <NUM> includes at least one link <NUM>' on each end and a mesh overlay <NUM> preferably extending therebetween. Link <NUM>' includes an integral hold-down clip <NUM>' comprising a depending extension <NUM>' and an upstanding tab member <NUM>'. As shown in <FIG>, links <NUM>' including the integral hold-down clips <NUM>' are provided on every third pitch rather than every pitch as shown in <FIG>. As a result of this spacing, the upstanding tab member <NUM>' can be wider so as to increase contact with the rail <NUM>. That is, by mixing links that have integral hold-down clips with links that do not have integral hold-down clips in some pre-determined pattern, it is possible to increase the width of the tab member and subsequently the strength of the tab member without interfering with the collapse of the belt or the articulation of the belt links around a roller. As should be apparent to one skilled in the art, link <NUM>' including an integral hold-down clip <NUM>' will be either a left-hand link or a right-hand link depending on which edge of the belt it is to be disposed, one being the mirror image of the other.

Referring also to <FIG>, a further exemplary embodiment which is not part of the invention includes belt <NUM> which combines the integral hold-down clip <NUM> with a U-shaped link <NUM> which also has a vertical extension above the top surface of the belt that serves as an edge guard <NUM> to retain product on the belt. An additional modification of belt <NUM> could include links with edge guards on every other pitch or every third pitch, etc. instead of every pitch as shown. A similar component spacing modification could apply to using links with integral hold-downs. As illustrated, the link <NUM> in <FIG> is considered a right-hand link and the link <NUM> shown in <FIG> is considered a left-hand link which is a mirror image of that shown in <FIG> and the correct link will be selected depending on which edge of the belt it is to be disposed.

Claim 1:
A conveyor belt (<NUM>) comprising
a plurality of spaced tractive rods (<NUM>);
a plurality of support rows (<NUM>) transversely disposed with respect to a direction of travel and interconnecting said plurality of spaced tractive rods (<NUM>);
a plurality of belt drive clips (<NUM>); and
a plurality of belt hold-down clips (<NUM>);
wherein said conveyor belt (<NUM>) includes opposing first and second outer edges and said plurality of belt drive clips (<NUM>) and/or belt hold-down clips (<NUM>) are disposed on at least one of the first and second outer edges of the conveyor belt (<NUM>) such that said belt drive clips (<NUM>) and belt hold-down clips (<NUM>) improve the edge drive capability of said conveyor belt (<NUM>);
wherein each of said plurality of belt hold-down clips (<NUM>) includes a base member having at least one opening and an upstanding member (<NUM>) disposed substantially perpendicular to said base member, each of said plurality of belt hold-down clips (<NUM>) further including opposing wing portions (<NUM>) extending from opposing sides of said base member,
wherein each of said plurality of belt drive clips (<NUM>) is generally J-shaped with a first leg portion, a second leg portion, and a connecting portion, the first and second leg portions defining two substantially parallel planes and the connecting portion defining a plane intersecting the two substantially parallel planes, each of said plurality of belt drive clips (<NUM>) having at least one opening in the first leg portion or the second leg portion and no openings in the connecting portion, the openings of each belt drive clip (<NUM>) existing entirely in the planes of the first and second leg portions,
wherein the first leg portion has two openings, the second leg portion has one opening, and the connecting portion connects the first and second leg portions,
characterized in that a plurality of said rows (<NUM>) comprise a U-shaped link (<NUM>) on each edge and a mesh overlay (<NUM>) extending therebetween.