GB2250564A - Fishplate - Google Patents

Abstract

To enable connection of respective elements (30, 40) adjustably and at different angles relative to each other without the need for a hinged fishplate or a range of angular connectors, a fishplate (10) is provided which has at least one oblique edge region (15, 16) between one of its longer and shorter edges, an arcuate slot (17, 18) adjacent the oblique edge region, and a notch (19) cut into the other of its longer edges. A releasable fastener (50) engaging through the arcuate slot (17, 18) enables connection and/or adjustment of the disposition of a respective element (30, 40) relative to the fishplate. An additional fastener (50) through a further aperture (23) may usefully serve as a pivot point during adjustment and/or for more secure connection at the selected angular disposition. <IMAGE>

Description

FISHPLATE This invention concerns a fishplate, particularly but not exclusively for joining together ladder-like sections to form a structure for supporting electric cables. Such structures are commonplace on oil rigs and in chemical plants and similar installations.

The ladder sections in question are conventionally formed of steel, either mild steel with galvanised finish, or stainless steel. Typically they comprise parallel channel section runners, with flanges defining the channels directed towards each other, connected at intervals by perpendicular cross-pieces, which are often apertured. Fishplates for end to end connection of adjacent ladder sections, in alignment with each other, are well known. When adjacent sections need to extend at an angle to each other, various right angled connectors, or connectors of other fixed angular shape are available for use. Additionally two-part hinged fishplates are available to cater for variation or adjustment in the angle at which adjacent sections may extend relative to each other.

An object of the present invention is to provide an alternative to known fishplate connectors which can be used either for straight end to end connection of ladder sections, or for connection of such sections where the plane of one is to extend at an angle relative to the plane of the other, thereby reducing the need for production/selection of different configurations of connector for these different situations.

A further object is to provide a fishplate which enables connection of adjacent ladder sections at an adjustable angle relative to each other, yet which is less expensive to produce than currently available hinged fishplates.

According to a first aspect of the invention a fishplate is provided which consists of a substantially planar web having opposing longer edges and opposing shorter edges, an oblique edge region extending between one of said longer edges and one of said shorter edges, an arcuate slot adjacent said oblique edge region, and a notch cut into the other of said longer edges intermediate its ends, such that another member, such as a channel section member, is connectable thereto at selected angular dispositions by a fastener engaging through the arcuate slot.

When the fishplate is used, as intended, for connecting a channel section member at a selected, adjustable angle to another element, the fishplate is arranged in and fastened to the base of the channel and the lateral flanges of the channel section are provided for by locating in the notch and by the oblique edge region, lying opposite the notch, whenever the channel section extends at an angle other than 1800 relative to the longitudinal extent of the fishplate.

The oblique edge region of the fishplate may be chamfered. Indeed it may curve to an extent substantially corresponding to the curvature of the arcuate slot. In other words the arcuate courses of the edge region and of the slot may be concentric so that the distance between the slot and the oblique edge of the plate is substantially constant.

In practical embodiments the arcuate slot may subtend an angle of approximately 45 , thereby limiting the angle of the connected channel section member relative to the longitudinal extent of the fishplate to approximately 45".

Additionally or alteratively, the notch in the fishplate may be defined by an edge lying opposite the oblique edge region, which extends at approximately 45" to the longer edges of the fishplate, thereby limiting the angle of the connected channel section member relative to the longitudinal extent of the fishplate to approximately 45".

However, these angular limitations are not essential and may vary in other embodiments.

The fishplate is advantageously provided with at least one further aperture, situated between the notch and the shorter edge to which the oblique edge joins, whereby a further fastener can engage. In this respect, a more reliable connection is obviously achieved if a respective fastener is secured not only through the arcuate slot, but also through an aperture, which is spaced therefrom.

The fishplate of the invention is substantially rigid and is suitably made of steel by any conventional method of fabrication.

According to a second aspect of the invention, a fishplate is provided which consists of a substantially planar web having opposing longer edges and opposing shorter edges, respective oblique edge regions extending between one of said longer edges and each of said shorter edges, respective arcuate slots adjacent each of said oblique edge regions, and a notch cut into the other said longer edge intermediate its ends, so that respective members, such as channel section members, can be connected thereby, each member being connectable to the fishplate at a selected angular disposition by a fastener engaging through the relevant angular slot.

Thus in accordance with the second aspect, both ends of the plate are provided with means for adjustable angular connection of respective channel section members.

In embodiments where, at each end, the arcuate slot subtends an angle of approximately 45 , that allows for two channel section members being connected by the fishplate to extend anywhere between straight alignment and at right angles to each other, with the notch being of appropriate shape and size to accommodate the adjacent side flanges of the respective channel members.

A practical embodiment of the fishplate of the invention will now be described with reference to the accompanying drawings, in which: Fig. 1 is a side view of the exemplary fishplate; Fig. 2 is similar view illustrating connection of two channel section members by the fishplate of Fig. 1, at an angle of approximately 45" relative to each other; and Fig.3 is a view similar to Fig. 2 but wherein the two channel section members extend approximately at right angles to each other.

Referring to Fig. 1, this exemplary fishplate 10 comprises an elongate plate of mild steel approximately 3mm thick and approximately 240mm long by 120mm wide.

Opposing longer and shorter side edges are designated 11, 12 and 13, 14 respectively. Chamfered corner regions 15, 16 are provided at one side of the fishplate between the longer edge 11 and each of the shorter edges 13, 14. Respective arcuate slots 17, 18, with rounded closed ends, extend adjacent each of these chamfered corner regions 15, 16, and with similar curvature, so that the width of material between the slot and the edge is roughly constant (approximately 15mm) in each case.

In this particular example, both slots and chamfered edges subtend an angle of about 45".

A V-shaped notch 19 is cut into the other longer edge 12 approximately mid way between its ends, the respective notch defining edges l9a, 19b in this case formed approximately at right angles. Between the notch 19 and each shorter edge 13, 14, two spaced apertures 21, 22 and 23, 24 are provided in alignment with the ends of the respective arcuate slots 17, 18.

For connecting together the ends of two channel section members, 30, 40, which have base webs already provided with fixing apertures for bolts, this fishplate 10 is inserted part way into the channel base of the end regions to be joined, as readily apparent from Figs. 2 and 3.

Each member 30, 40 can be selectively secured anywhere between two limiting positions which are illustrated in Fig. 2, namely in alignment with the longitudinal extent of the fishplate 10, or at approximately 45" thereto.

In the first extreme position (shown for member 30), bolts 50 are fastened through the aperture 22 closest to the notch 19 and through the respective slot 17 in abutment against the end of the slot 17 closest to the middle to the fishplate. When both members 30, 40 are connected in this way, they are joined in a straight line.

For additional security of connection when either of the members 30, 40 is in alignment with the longitudinal extent of the fishplate 10, a further bolt 51 can be fastened through the other aperture (21 or 24 respectively), as shown in Fig. 2, since that aperture 21, 24 should then, in most cases, line up with another aperture in the channel base.

In the second extreme position (shown for member 40), a first bolt 50 is again fastened through the aperture 23 closest to the notch 19, but this time a second bolt 50, which is fastened through the slot 18, abuts the other end of the slot closest to the end of the fishplate.

When both members 30, 40 are connected in this way, they extend approximately at right angles, as illustrated in Fig. 3.

Any angular disposition between these two extremes is obviously possible, and adjustment is easily accomplished by loosening the nuts on the two securing bolts 50 and swinging the relevant channel member 30, 40 along with sliding of the relevant bolt 50 along the slot 17 or 18 to the desired position before retightening both nuts. In this respect, the bolt 50 extending through the aperture 22 or the aperture 23 may usefully serve as a pivot pin during adjustment of the relevant channel member 30 or 40, respectively, relative to the plate 10.

As clearly shown in Figs. 2 and 3, this particular fishplate 10 is designed to be a snug fit in the channel bases of the members 30, 40 and the side flanges of the respective channel section members 30, 40 are, in effect, guided by the relevant chamfered regions 15, 16 and the opposing notch defining edges 19", 19b upon angular adjustment.

In accordance with the invention, instead of providing a separate hinge connection (as in previously known hinged fishplates) articulation can take place directly at the connection between the fishplate and one or both channel section members owing to the provision of the arcuate slots.

For connecting ladder-like sections having channel section runners, respective fishplates will obviously be used at each side and corresponding adjustment at each side will be possible in the manner already outlined.

As previously mentioned, the illustrated embodiment is only exemplary, and its details are not to be considered as limiting. Many variations are possible within the general scope of the invention enunciated hereinbefore, as will be apparent to those skilled in the art. In particular, it would be possible to have a fishplate with only a single arcuate slot adjacent one corner, but slots at both ends are preferable to allow greater versatility.

Claims (8)

1. A fishplate consisting of a substantially planar web having opposing longer edges and opposing shorter edges, an oblique edge region extending between one of said longer edges and one of said shorter edges, an arcuate slot adjacent said oblique edge region, and a notch cut into the other of said longer edges intermediate its ends, such that another member is connectable thereto at selected angular dispositions by a fastener engaging through the arcuate slot.

2. A fishplate as claimed in claim 1 wherein the oblique edge region is chamfered.

3. A fishplate as claimed in claim 2 wherein the oblique edge region and the arcuate slot have substantially the same curvature so that the distance between the slot and the oblique edge of the plate is substantially constant.

4. A fishplate as claimed in claim 1, 2 or 3 wherein the arcuate slot subtends an angle of approximately 45".

5. A fishplate as claimed in any preceding claim wherein the notch is defined by an edge, lying opposite the oblique edge region, which extends at approximately 45" to the longer edges of the fishplate.

6. A fishplate as claimed in any preceding claim and having at least one further aperture situated between the notch and the shorter edge to which the oblique edge joins.

7. A fishplate consisting of a substantially planar web having opposing longer edges and opposing shorter edges, respective oblique edge regions extending between one of said longer edges and each of said shorter edges, respective arcuate slots adjacent each of said oblique edge regions, and a notch cut into the other said longer edge intermediate its ends, so that respective members can be connected thereby, each member being connectable to the fishplate at a selected angular disposition by a fastener engaging through the relevant angular slot.

8. A fishplate substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.