IE41970B1 - Chain link for conveyor chain - Google Patents

Abstract

1495076 Making conveyer chain links MACHINENFABRIEK GEFRA BV 16 Dec 1975 [17 Dec 1974] 51518/75 Heading B3A [Also in Division B8] A link for a conveyer chain is made from a sheet metal blank 1, Fig. 1, having at least one hinge-tongue 2, at least one opposite hingetongue 3 out of alignment with the tongue(s) 2, and a lateral projection 5 on at least one of the tongues which engages beneath a guide 6, Fig. 3, for the completed conveyer to prevent undue lifting of the load-bearing surface. The tongues 2, 3 are rolled to form hinges 2a, 3a, the spaced hinges 3a on one link being connected by a pin 4 to the central hinge 2a on another link to form a chain.

Description

This invention relates to a link for a conveyor chain and more particularly to a link for a conveyor chain capable of being deflected to one side or the other whilst the load bearing surfaces of the links are restrained against deflection from a load-bearing plane.

In U.S. Patent Specification No. 3,262,550 there is described a chain link, generally moulded from a plastics material, which presents a substantially rectangular load bearing surface with pivot pin bearings below the transverse edge regions of the link, the pivot pin bearings along a leading transverse edge of the link being co-operable with the pivot pin bearings on the trailing edge of an identical link to allow a pivot pin to pass through the assembled bearings to pivotally connect the two links. To prevent the load bearing surface from deflecting unduly from its load bearing position as the conveyor changes its direction to one side or the other, the links pass between side rails which present inclined faces to the outermost sides of the pivot pin bearings and the outermost sides of the pivot pin bearings are formed, by moulding or subsequent machining, with inclined faces to co-operate with the inclined faces of the conveyor guide. Thus, the links are retained substantially horizontal as the conveyor veers.

A difficulty with the above described prior art links is that they are expensive to manufacture and, because the guide surfaces are inclined and subject to wear, the life of such links and guide rails is limited. - 2 41970 Alternative link forms are disclosed in the British Patent Specifications Nos.1,216,939 and 1,217,126 and wherein a separate part is welded to the undersurface of the load bearing panel of a formed link to provide lateral guides engageable with the conveyor guide means to retain the link load bearing surfaces substantially horizontal as the conveyor veers. However, as can be expected, the separate formation of the separate part and the additional aligning and welding operations greatly add to the expense of manufacturing such links.

According to the present invention there is provided a link for a conveyor chain made from sheet metal and comprising a substantially rectangular load-bearing surface; pivot pin bearings at the transverse edge regions of the link and by which the link can be pivotally connected to a leading link and a following link in a conveyor chain and lateral extensions or projections presented by selected pivot pin bearings, integral with said bearings, and capable of engaging with guide surfaces of the conveyor chain guide means to prevent undue displacement of the link from a desired plane for the substantially rectangular load bearing surface.

Such link may present at one transverse edge one pivot pin bearing centrally disposed along said edge and at the other transverse edge, two pivot pin bearings spaced apart by a distance at least equal to the axial length of the centrally disposed bearing.

Preferably the lateral projections are formed on the outer surfaces of the two spaced apart pivot pin bearings.

Preferably the lateral projections are formed only on those parts of the pivot pin bearings spaced apart from the load bearing surface of the link and the load bearing surface overlies the lateral projections to allow part of the conveyor chain guide means to enter therebetween.

The lateral projections may conveniently present guide surfaces to the conveyor chain guide means substantially parallel to the plane of the said load bearing surface.

The invention also envisages a sheet metal blank for a link for a conveyor chain and comprising a substantially rectangular surface intended to be the load bearing surface for the link, at least one tongue extending from a first transverse edge of the rectangular surface, at least one tongue extending from the second transverse edge of the rectangular surface, out of longitudinal alignment with the tongue or tongues on the first transverse edge, and a lateral projection on a side edge of at least one of said tongues directed outwardly with respect to the blank and located adjacent the mid-length of the respective side edge.

Preferably the first transverse side edge presents one centrally disposed tongue and the second transverse edge presents two tongues spaced apart by at least the width of the tongue on the first transverse edge and a lateral projection is formed ori the outwardly facing side edge of each of the two tongues of the second edge.

The invention further envisages a conveyor chain formed of a plurality of such links and wherein the trailing edge of each link is connected to the leading edge of the following link by a pivot pin passing through all the pivot pin bearings presented by the adjacent edges of the two links and wherein each link presents, at its leading or trailing regions, said lateral projections for engagement with the conveyor chain guide means.

The invention will now be described further, by way of example, with reference to the accompanying drawing, wherein Fig. 1 shows a perspective view of the blank for manufacturing a conveyor link, Fig. 2 is a view of a conveyor link, and Fig. 3 is a front view of the link of Fig. 3 showing the engagement of one lateral projection with a conveyor chain guide means.

Referring to Fig. 1 a blank for making a conveyor link is stamped or cut out from a metal sheet or strip and comprises a substantially rectangular - 4 41970 part 1 with, on one transverse edge, a centrally disposed tongue 2 and on the other transverse edge two tongues 3 which are laterally spaced. By bending over the tongues 2 and 3, there are formed pivot pin bearings 2^, 3a_ for pivot pins 4, by which successive links in a conveyor chain are interconnected. In case of straight conveyor runs, it is sufficient for the links to rest on rails the which extend on either side of the bearings 2^, 3 a so that/under sides of the load bearing surfaces of the links rest on the rails and with the pivot pin bearings between the rails.

However, when the conveyor run is to be deflected to the left or right guide means are provided for retaining the load supporting surface in a desired horizontal plane and thus the blank includes lateral projections 5 from the outer side edges of tongues 3 which projections, when the pivot pin bearings are formed, are adapted to engage underneath a guide of the conveyor guide means and which guide 6 will be formed at least in the outer bend in the bearing rail profile.

Fig. 1 shows by dotted lines in the blank the boundary surfaces of tongues 3 in a blank for a chain link without bend guides. It follows therefrom that the projections 5 may remain within said boundaries, so that no additional material is required. The transverse widths of the tongues 2 and 3 may be chosen in function of the desired tensile strength and lateral flexibility.

It will be appreciated from the drawings that when the tongues 2 and 3 pin are rolled to make the pivot/bearings 2a_ and 3a. the transverse width of the tongue 2, being less than the transverse distance between the tongues 3, allows the pivot pin bearing 2a. of one link to be inserted between the pivot pin bearings 3£ of an identical and adjacent link so that a single pivot pin 4 can pass through the assembled bearings2_a and 3a. to pivotally retain the assembled links.

Although the specific embodiment has been described by way of an example which presents one pivot pin bearing at one transverse edge and two pivot pin bearings at the other transverse edge it will be appreciated by persons skilled in the art that different numbers and combinations of pivot pin bearings may be provided without departing from the scope of this invention.

Claims (12)

1. A link for a conveyor chain made from sheet metal and comprising a substantially rectangular load-bearing surface; pivot pin bearings at the transverse edge regions of the link and by which the link can be pivotally connected to a leading link and a following link in a conveyor chain and lateral extensions or projections presented by selected pivot pin bearings, integral with said bearings,and capable of engaging with guide surfaces of the conveyor chain guide means to prevent undue displacement of the link from a desired plane for the substantially rectangular load bearing surface.

2. A link for a conveyor chain as claimed in Claim 1 in which the link presents at one transverse edge one pivot pin bearing centrally disposed along said edge and at the other transverse edge, two pivot pin bearings spaced apart by a distance at least equal to the axial length of the centrally disposed bearing.

3. A link for a conveyor chain as claimed in Claim 2 in which the lateral projections are formed on the outer surfaces of the two spaced apart pivot pin bearings.

4. A link for a conveyor chain as claimed in Claim 1, 2 or 3 in which the lateral projections are formed only on those parts of the pivot pin bearings spaced apart from the load bearing surface of the link. the

5. A link as claimed in Claim 1, 2, 3 or 4 in which/load bearing surface the overlies the lateral projections to allow part of / conveyor chain guide means to enter therebetween,

6. A link as claimed in Claim 1, 2, 3, 4 or 5 in which the lateral projections present guide surfaces to the conveyor chain guide means and which guide surfaces are substantially parallel to the plane of the said load bearing surface.

7. A sheet metal blank for a link for a conveyor chain and comprising a substantially rectangular surface intended to be the load bearing surface for the link, at least one tongue extending from a first transverse edge of the rectangular surface, at least one tongue extending from the second transverse edge of the rectangular surface, out of longitudinal alignment with the tongue or tongues on the first transverse edge, and a lateral projection on a side edge of at least one of said tongues directed outwardly with respect to the blank and located adjacent the mid-length of the respective side edge.

8. A sheet metal blank as claimed in Claim 7 in which the first transverse side edge presents one centrally disposed tongue and the second transverse edge presents two tongues spaced apart by at least the width of the tongue on the first transverse edge and a lateral projection is formed on the outwardly facing side edge of each of the two tongues of the second edge.

9. A link for a conveyor chain as claimed in any one of Claims 1 to 6 made from a blank as claimed in Claim 7 or 8 by rolling or bending the tongues to form pivot pin bearings below the load bearing surface of the link.

10. A conveyor chain formed of a plurality of links as claimed in any one of Claims 1 to 6 or Claim 9 and wherein the trailing edge of each link is connected to the leading edge of the following link by a pivot pin passing through all the pivot pin bearings presented by the adjacent edges of the two links and whereby each link presents, at its leading or trailing regions, said lateral projections for engagement with the conveyor chain guide means.

11. A link for a conveyor chain substantially as hereinbefore described with reference to and as illustrated in Figs. 2 and 3 of the accompanying drawings.

12. A blank for a link for a conveyor chain substantially as hereinbefore described with reference to and as illustrated in Fig. 1 of the accompanying drawings.