GB2615116A - A method and template for creating a component for an enclosure - Google Patents

Abstract

A weldable template, used for creating an enclosure, may have a face 10, and sides 18, joined by folds. A projection 24 in one side may mate with a recess 22 in an adjacent side, to create an interlocking self-clamping join, e.g. in creating a lid or box of an electrical enclosure. Adjacent edges may be arc welded together, creating a weld seam along the interface of the box-joint. A laser cutter may be used to cut the template from a metal sheet, e.g. stainless steel. Metal inert gas (MIG), tungsten inert gas (TIG), shielded metal arc welding, flux welding, cored arc welding or plasma arc welding may be used. The electrical enclosure may be cuboid or other shapes. Edges may have multiple fingers 24 and complementary holes 22. Welding may be manual or via a robot.

Description

A N/bt hod and Terrpl at e f or Cr eat i ng a Corrponent f or an End l osure The present invention relates to a terrpl ate f or creating a corrponent of an end l osure and a rret hod of creating such an end osure and rel at es particularly, but not exclusively to t he f or rrat i on of stainless steel end l osur es for use in t he locations where hygiene is particularly i rrport ant.

The use of t he we! di ng process to join t nat er i al s together such as rretal is corroonpl ace. This practice is widely used when creati ng nut al conponents f or an end I osure, f or exarrpl e an electrical end l osure, wal I -rrount ed or floor standing end osur es. Nile! di ng has advantages over other j oi ni ng rret hods such as rivets or bolts by creating a strong support f or a load with t he added benefit of being lighter overalI, wat er proof, having a I ow corrosi on rate and a hi gh tensile strength.

The fully wel ded joint can t hen be ground and polished to a very hi gh standard to satisfy the hygiene levels ch are derranded by the end user. To f use any two nut al corrponents together a highly I ocal i sed heat source ( between 30006C and 20, 0006C) i s directly applied to t he j oi nt edges. This heat source is typi cal I y created by an electrical arc f orrri ng between t he base nut al and either a conti nuous consurrabl e el ect rode dun i ng net al i nert gas ( MG) wel di ng or a rrDnoconsurrabl e el ect r ode used duri ng tungsten i nert gas (TI G) wel di ng. However, a di sadvantage of usi ng an arc wel di ng process is the con-pl ex t her MD-rrechani cal behavi our of nut al when ext r erre heat is applied. Non-uniform stresses can arise that cause expansi on and cont racti on of t he heated rrater i al Wui ch can lead to distortions. The initial application of t he heat causes corrpressi ve stress in t he surrounding area and during the cool down phase, when t he heat source is retracted, tensile stress occurs. This can cause conpl i cat ed rmt i on control such as -2 -angul ar distortion, bowl ng, shri nkage, t W sting or buckling of t he two rret al s that are being joined. A distortion could al so cause fractures i n t he vrel d leading to a reduced strength, reliability and waterproof i ng of t he f orrred corrponent. If t he lid is badly distorted, a poor seal between t he lid and end l osure body rray be created, thich I I allow water to enter t he end l osure.

Preferred errbodi rrent s of t he present invention seek to over corm or al I evi ate the above descri bed di sadvant ages of t he 10 prior art.

Accordi ng to an aspect of the present invention there is provi ded a rret hod of cr eat i ng a corrponent f or an end l osure corrpri sing t he steps: cutting a terrpl at e f roma metal sheet, said d terrpl at e corrpri si ng, a f ace, a plurality of sides each def i ned by a fold Iine connecting said d si de to said d face, and a pair of first edges extending from sai d f ol d I i ne and second edges j oi ni ng sai d pai r of f i rst edges Merei n adj acent f i rst edges of adj acent si des define wel d edges to be wel ded together, at least one recess cut into one of said d pai r of vriel d edges, and at least one protr usi on extending from the other of said d wel d edges, folding sai d terrpl at e al ong said d fol d lines such that said d prot rusi on extends into sai d recess, and creating a wel d by wel di ng said d adj acent wel d edges.

By creating a protrusi on and recess on adj acent sides and aligning them together a sel f -cl arrpi ng join is f orrred. This 'sel f-cl arrp_ I ni ts mwerrent of t he two rret al s by t he wel di ng process and in ni in ses the effects of t he non-uni form expansi on and t he stresses t hat arise Men t he heat source is applied. By I i rri ti ng any rroverrent in the wel d or between two rret al sheets, any tint delaying procedures such as realigning t he rret al or redoing the wel d can be avoi ded. Furt her rror e, it Ii nits t he occurrence of stress fractures, cracks or distortions t hat could form in t he f ut ure or dun i ng t he vs.el di ng procedure t hereby i rrprovi ng the strength and vvat erproof i ng of t he corrponent.

The i rrportance of achieving a perfect joint first ti rre Men using expensive stai nl ess steel is absolutely critical. Wien using ru I d steel corrponent s, Wii ch can be easily pai nted to nask over cracks and maknesses, expensive stai nl ess steel nust be perfect, thus the need to adopt except i onal wel di ng techni ques as descri bed.

In a preferred errbodi rrent the cutting step is undertaken using a laser cutter.

In anot her preferred errbodi rrent Wier ei n t he sAel di ng step corrpri ses an arc sAel di ng process. This can include rret al i nert gas ( MG) or tungsten i nert gas ( TIG) vsel di ng.

In a further preferred errbodi rent the sAel di ng step is undertaken by a robot (autorrat ed) or a person.

Accordi ng to another aspect of t he present invention t here is provi ded a terrpl ate for creating a conponent of an end l osure corrpri si ng: a face; a plurality of si des each def i ned by a fold Iine connecting said d si de to said d face, and a pai r of first edges extending from sai d f ol d I i ne and second edges j oi ni ng sai d pai r of f i rst edges Wier ei n adj acent f i rst edges of adj acent si des define wel d edges to be vsel ded together; at least one recess cut into one of said d pai r of sAel d edges; and at least one protrusion extending from the other of said wel d edges.

Preferred errbodi rrents of t he present i nventi on wi I I now be descri bed, by way of exarrpl e onl y, and not i n any I i rri tat i ve sense with ref erence to t he accorrpanyi ng drawings in Wii ch: -Figure 1 is a planar vi ew of a terrpl ate of t he present invention; and Figure 2 is a cl oseup partial vi ew perspective vi ew of t he terrpl ate figure 1 in a fol ded and pre-wel ded condi ti on.

Ref erri ng to both figures, a corrponent f or an end l osure, such as a lid or box is initially cut from a sheet rretal such as stai nl ess steel. This enclosure is used to protect electrical cabling or other such corrponents from foreign bodi es, liquids or t he at her. In industrial applications t he rret al sheet is typically cut using a laser or pl asrra cutter but this can equally be achi eyed by usi ng srral I er scal e tool s such as a hacksaw, circular saw or angle gri nder. However, it should be not ed that due to the i rrportance of accuracy needed for t he successful creati on of this product al I net hod steps are carried out using hi gh preci si on.

Figure 1 shows t he layout and rrai n sect i ons of t he terrpl ate 1 after it has been cut but before it is folded i nto t he corrponent shape. It includes a substantially square face with four sides extending from therefrom Each side 12 is connected to the face 10 by a fold line 14. The fold Iine is not a physi cal line drawn or rrarked onto t he tenpl ate 1 before being asserrbl ed, but a junction between t he face 10 and t he sides 12 when t hey are f ol ded. The sides 12 are def i ned by a pair of first edges 16 t hat extend f romt he fold Iine 14 with a second edge 18 connecting t he first edges together. These sides 12 and face 10 are the rrai n surfaces that rrake up the structure of t he corrponent how.ever addi ti onal features are present in t he terrpl ate 1 prior to t he corrpl eti on of the corrponent. In t he -5 -errbodi rrent shown, t he corrponent is substant i al I y cuboi d i n shape 4iith t he face 10 and si des 12 bei ng rectangular in shape. However, t he invention can al so be appl i ed to other shapes of corrponent.

al each si de 12 shown i n both figures 1 and 2 t here is either a recess 22 or protrusi on 24. These are situated rredi an to t he first edges 16. As they rrake up a pair, if t here is a recess 22 on one si de t here lAi I I be a protrusi on 24 on t he adj acent si de. It should be noted t hat the protrusi on 24 fits into t he recess 22 so that Wien these two corrponents, once folded, forma box joint. Fi gure 2 shows t he f orrrat i on of t he box joint 26 aft er t he si des 12 have been f ol ded correctly together. The area whi ch t he wel der welds al ong is def i ned as t he wel d edge and i ncl udes t he two adj acent si des 12 bei ng pl aced together al ong wi th t he box joint 26. By way of exarrpl e only, on a sheet of stai nl ess steel t hat is 1. 5rrm t hi ck t he protrusi on extends 2-3rrm al ong t he f i rst edge 16 and 1. 5rrm from the f i rst edge, t hat bei ng t he t hi ckness of sheet used. In contrast t he recess is cut approxi rrat el y 0. 5rrrn I arger than t he protrusion to ensure space f or t he protrusion to enter t he recess with a snug but accurate fit to form the box joint.

The net hod f or constructing t he end l osure from terrpl ate 1 after t he initial Iaser cutting is as f ol I ov's. The t errpl ate 1 i s f ol ded usi ng a press brake, a nachi ne used f or bendi ng sheet net al i nto an accurate form The use of hi gh preci si on tool s provi des t he accuracy needed to achi eve libel I -def i ned and correct I y posi t i oned recesses 22 and pr ot r us i ons 24. Once al I protrusi ons 24 from si des 12 are nestled into t he recesses 22 of adj acent si des, as hi ghl i ghted in figure 2, wel di ng can corrrrence. For preci si on and aest heti cal 1 y pl easi ng wel ds a tungsten i nert gas (TI G) v'el di ng tool 20 is used. Hovvever, this requi r es an experi enced wel der or robot to produce vvat ert i ght and aest heti call y accept abl e wel ds. 0 her types of wel di ng can al so be used such as rretal inert gas (M or shielded rret al arc we! di ng.

The wel der can start at either end of t he conponent but vvoul d usually begin at t he open end and wor k their way to t he base. As rretal t ends to contract and expand as it is heat ed and cool ed during t he wel di ng process, t he box joint 26, created by t he prot rusi ons 24 and recesses 22, rri ni rri ses or stops t he t her rro-rrechani cal rroverrent associ at ed Wth these di stort i ons t hereby ensuring t he wel d joining t he sides edges is correctly and evenly applied al ong its length. To rrake t he area around t he wel d srroot h, searri ess and free of jagged edges, t he surfaces are polished using different polishing abrasives either by hand or a ut orrat ed.

It ^Aii I I be appreci at ed by persons skilled in t he art t hat t he above errbodi rrent s have been descri bed by way of exarrpl e only and not i n any I i rri tat i ve sense, and t hat vari ous alterat i ons and rrodi f i cat i ons are possible thout depart ure f r om t he scope of t he prot ect i on whi ch is defined by t he appended cl ai us. For exarrpl e, the above errbodi rrent descri bes only one box j oi n per v1/4iel d edge. However, if t he conponent was rruch tall er, t hat i s t he sides were of increased Iength, t he corrpl ex rrot i ons associated Wth t he contracting and expanding net al during t he we! di ng process nay require two or nor e box joins per wel d edge.

Fun her nor e, t he above errbodi rrent descri bes t he use of MG and TIG wel di ng. However, other such wel di ng t echni ques coul d be used including, but not I i rri ted to, Shi el ded Wtt al Arc V\el di ng, Fl ux VC di ng, Cored Arc V\el di ng and PI as rra Arc VC di ng.

Claims (4)

1. CI a i ITS 1. A net hod of creating a corrponent f or an enclosure corrpri si ng t he steps: cutting a terrpl at e f roma rret al sheet, said d terrpl at e corrpri si ng, a f ace, a plurality of si des each def i ned by a fold Iine connecting said d si de to said d face, and a pai r of first edges extending from sai d f ol d I i ne and second edges j oi ni ng sai d pai r of f i rst edges vther ei n adj acent f i rst edges of adj acent si des define vsel d edges to be sAel ded together, at least one recess cut into one of said d pai r of vsel d edges, and at least one protr usi on extending from t he other of said d we! d edges, folding sai d terrpl at e al ong said d fold lines such t hat said d prot rusi on extends into sai d recess, creating a we! d by sAel di ng said d adj acent sAel d edges.
2. 2. The rret hod of claim 1 vtherei n t he cutting step corrpri ses using a laser cutter.
3. 3. The net hod accordi ng to any precedi ng cl ai m *her ei n t he sAel di ng step corrpri ses an arc vseel di ng process.
4. 4. A t errpl at e f or creating a corrponent of an end I osur e corrpri si ng: a face; a plurality of si des each def i ned by a fold Iine connecting said d si de to said d face, and a pai r of first edges extending from sai d f ol d I i ne and second edges j oi ni ng sai d pai r of f i rst edges vther ei n adj acent f i rst edges of adj acent si des define l d edges to be vsel ded together; at least one recess cut into one of said pair of \AEI d edges; and at least one protr usi on extending from the other of said vvel d edges.