CA2139152C - Water cooled welding torch - Google Patents

Abstract

The supply of water to the water jackets in the torch is fed through feed and return hoses, clamped to pipe spigots. The spigots are a self-locking-taper fit in a block, and are drawn into the block with a drawring, using bolts. This spigot-to-block connection is highly robust, has good electrical conductivity, and is well-sealed against water leakage. The electrical supply to the arc is fed through two cables, which lie inside the feed and return water hoses.

Description

WATER-COOl,gb W~~bING TORCH
This invention relates to welding~~ipes renders each pipe highly torches, and to the equipment tesistant to kinking. Thus, both ancillary to such torches. In t:he water pipes arid the cables particular, the invention relateseach to the supply of cooling orator take benefit from being placed and together.
other fluids from a service station co the torch. It is the conventional practice, in water cooled welding torches, Gne of the problems facing the to designer of welding torches is clamp the rubber water pipes to that brass pipe-spigots, and the the conduit connecting the torchc~~nventional arrangement is that to t:xe pipe spigot is screw~threaded the service station should be into a block. The invention flexible and easily manipulable,p~ovides an alternative to the and yet the conduit should be normal practice of pzoviding a strong, and especially it shouldscrew thread connection between be the resistant to kinking and creasing, pipe-spigot and the block.
The invention is especially advantageous in this regard. T~;e invention provides a plug-and-In socket connection between the the invention, the electrical pipe-current is fed rom the service spigot and the black. A draw ring station to the torch by two is provided for drawing the plug electrical cables. The two cablesinto the socket. A bolt extends pas$ one inside the water feed rom the block, and makes a screw pipe thread connection whereby the and the other inside the water draw return pipe, within the conduit.ring may be urged forcefully bividing the cable into two turnsrelative to the block, thereby out to b~ highly advantageous: ti~~htening the plug into the surrounding each of the two cablessocket.

by water means that the cables run cool even when transmitting heavyPrea~erably, provision is made currents; and providing a metal also Cable inside the (rubber) water foi- forcefully loosening the plug from the socket: when this is done, x the plug and socket connection can Fig 6 is a pictorial view of a be of the self-locking~taper welding torch;
type, which is very efficient arid F_Lg 7 is a view corresponding to reliable fxom the standpoints Fig 3 of another embodiment of of mechanical strength, electrical the invention.

corxductivity, and watertightness.

Fig 8 is a cross-section of a welding torch;

Fa.g 9 is a cross~section of a DETATLED DBSGRIPTION OF PREF$~E~handle of the torch of Fig $;

EMBppIMENT Fig 10 i8 a cross-section on line Q-Q of Fig 8;

By way of furthex' explanation Fi.g 11 is a cxoss-section on of line the invention, exemplary P,p of Fig 9;

embodiments of the invention Fi.g 12 is a cross-section, like will now be described with reference Fig 11, of another torch;
to the accompanying drawings, in Fig 13 i$ a cross-section of the which: handle area of another torch;

Fig 1 is a cross-sectional side Fiq 14 is a cross-section of a view of a portion of a water- portion of the handle of supple system for a welding another torah.

torch, which embodies the invention; The apparatuses shown in the Fig 2 ,is a diagrammatic view, accompanying drawings and described shown end-~on, of a draw-ring below are exampi.es which embody the component of the system shoran invention. Tt should be noted that in Fig 1; th~~ scope of the invention is Fig 3 is d cross-sectional side defined by the accompanying claims, view of another portior~ of the am9 not necessarily by specific water-supply system shown in fe~~tures of exemplary embodiments.

fig 1;

Fig 4 is a view on line 4-4 of Iri the drawings, numerals used in Fig 3; more than one drawing refer to the Fig 5 is a section on line 5-5 sarne or essentially similar of Fig 3; components .

2 For a welding operation of the type through-hole into which is received with which the invention is a stem 18. The stem 1B is concerned, it is the usual practice detachable from the fixture 12, to provide a service station. This being held in place by means of a service station provides: a welding bolt 20. With the stem present in current of electricity; anti- ~:he fixture, welding wire 23 is oxidising gas; a motor for feeding inserted into the stem; the wire is welding Wire to the Weld= C~n a motorised reel, whereby the (optionally] a vacuum source for v~irs u~ay be fed forward extracting fumes; and, in this controllably, in the conventional particular case with which the manner. The wire 23 is received invention ie concerned, a pumped inside a close-coiled helical supply and xeturn of cooling water s;aring 25, which serves as a guide for the hand--held welding torch. fur the wire on its passage to the wedding torah. A length of plastic These services as supplied fxom the tubing 27 is fitted to the stem ig;
service station are fed to the gF~s from the port 16 is conveyed welding torch through various pipes inside the tubing 27, along with and tubex forming a main conduit tt;.e spring 25 and the wire 23.
10. The conduit 10 is flexible in order to allow the torch to be So far, the above-described manipulated by the gelding arrangements fox supplying the operator. welding current, the welding wire, and the gas, into the flexible The service station includes, as conduit follow convsnti.onal shown in Fig I, a fixture 12. The practice.
fixture 12 is connected to the source of welding current in the. zt is conventional also to provide service station via a lug 14. The a water supply to the torch, the anti-oxidising gas, being argon, wai:er-feed and water-retuxn pipes carbon dioxide, or as required, is altio being contained within the fed into the fixture 12, via a port conduit. However, the particular 16. mariner in which the water--feed and -return pipes are arranged in the The fixture 12 is formed with a ap~~aratua shown in Fig 1 is

3 especially advantageous, as willA length of flexible electrical now >ae described, cable 49 is braced or soldered into ~'he stem 18 carries a block hole 50 in the pipe-spigot.
29, which is brazed to the stem. I'ig 1 shows the water-feed pipe A 45.
water feed poxt 30 and a 9'he watex return pipe xs of similar corresponding water return port e~rrangement. Thus, bath the water-32 teed pipe and the water-return az~e provided in the bleak 2g. pipe The are equipped with flexible ports 30,32 communicate with electrical cables. The large respective sockets 34. Each socketelectrical current required in 34 is of conically tapered form.heavy-duty welding is thus split between two cables.
Respective pipe-spigots 36 are ~.nserted ~.n the sockets 34.
A plug end 38 of the pipe-spigot is A~3 compared with a single cable, a d=widing the electrical duty taper fit into the socket 34. between two cable$ means that An each O-ring 40 on the p~.ug end 38 c~~ble can be a little less than contains and seals water from hz~lf the Current-carrying cros the s port 30. The water enters the section than the corresponding hollow interior 43 of the pipe- single cable. The reason each spigot 36. A rubber tube 45 is half-cab7,e can be a little less clamped to the pipe-spigot 36. than half the size is that each Water from the hollow interior half-cable is contained in its 43 own o the pipe-spigot passes into respective water jacket, whereby the eo~oling of the cable is enhanced.
tube 45 via radial, holes or slots

4~' When the plug..end When only a single 38 is inserted cable was tightly in the socket prnvided, as in conventional 34, not only de>;igng, the conduit is the pipe-spigot 10 could be 36 secured very qu.Lte stiff. As a well mechanically to result, the the block 29, we~.ding operator but also there is an found it quite excellent, low tiring to operate resistance, electrical the torch through contact a ~rorking day.
between the pipe-spigot and the block.

Splitting the cable into two, :34. (The angle of the taper and in the placing two smaller-than-half :sockets zs such that the taper cables one in the water-feed pipel.s and the other in the water-returnc~elf-lacking. ) The bolt 60 pipe. results in a great is improvement in physical flexibilityFscrew-threaded into the draw-ring and manipulability to the conduit;~~2, and passes through a crorreeponding plain hole fn the k~lack 29.

so much so as to extend by hours the period the operator can work Zhe relative dispositions of comfortably. the draw-ring 52, the bolt 60, and the pipe.spigots 36, is shown in In order to ensure the pipe-spigotsFig 2.
36 are pressed firmly into the It will be understood that the sockets 34, a draw-ring 52 is water feed arid return ports provided. The draw-ring has U- 30 in shaped cut-outs 5a, which engage the block 29 correspond to the complementary recesses 56 definedl~3xout as shown in Fig 2, although between two collars 58 provided shown out of position in Fig on 1.
the pipe-spigot. The draw-ring 52 does not touch the si~em 1$, in that a hole 63 in the d~;aw ring provides adequate clearance.

The draw-ring 52 is separate from the black 29. when the draw-ring Af~ descri.bed, the Conduit 10 is forced to move to the right includes the welding wire 23 (Fig 1), it urges the pipe-spigotsinside 36 tightly into the sockets 34 it.s guide spring 25 surrounded in by the block 29; when the draw-ring the gas-conveying plastic tubing is forced to the left, it 27; also the conduit includes disengages the pipe-spigots from the the block. The draw-ring 52 is two electrical cables 99 inside moved to the right by tightening their respective water-conveying a~ rubber tubes 45. Thus, it will bolt 60. To move the draw ring be to noted that in the conduit 10, the left, the bolt 60 is slackened,the and then the head of the bolt three fluid-conveying flexible may pi;?es or tubes 27,45 all have be tapped to the left to drive respective central internal "cores"
the of metal; these "cores" serve pipe-spigots free from the socketsto prov~.de excellent resistance to kinking of the pipes and tubes, block at 69.
and to other types of mechanical failure. The block 69 is brazed over a brass tube 72, which foams a component The conduit 10 is therefore veryof sturdy in the sense o,f being the gooseneck of a welding torch able 70 to resist the abuse which is (Fig 6). The tube 72 is in turn always brazed over a stem 74. The stem likely to be imposed upon it 74 in a is a thick-walled tube, the walls practical welding shop, especiallyof which are cut flat as shown abusive snaggings, twistings, at and 76 (Figs 3 and 4). The flats 76 the like. On the other hand, thus define passages 78 between none the of the components of the conduits-~em and the tube, for conveying as the feed and return water to and described is thick arid heavy, f~om the tozch 70.
and therefore the conduit i,s light in weight, and is comparatively very flexible, It is easy for the The internal layout of the torch operator to carry and manipulateis a such as to route the cooling water welding torch supported on such amound and through those components a off' the torch that tend to become conduit for long periods.

hat during welding, and can be The conduit 10 includes, and of is any suitable design. An example enclosed in, a conventional rubber/of a design of torch which is suitable canvas Cover. The cover is not for use with the invention i,s shown in Fig 1. shown in European patent application EP-93/202,778.2.

The other end of the conduit x0, where the conduit attaches to Th~~ block 69 is provided with the ta~~ered connections 80 for welding torch, will now be receiving the pipe-spigots 67, described.

Ho:Les are drilled from the outside In Fig 3, the arrangement ~.s of the block to connect the sockets repeated of a draw-ring that wii=h the passages 7B. The outer forces portions of these holes are then pipe-spigots into sockets in plugged, as shown at 81 in Fig a 3.
block. The draw-ring is shown at 65, the pipe spigots at 67, and the The draw-ring d5 has cut-outs welding current, starts the wire fox :Eeed-motor, eto, back at the accommodating a recess between :service station. The leads to collars of the pipe-.spigot 67, the as trigger are also present in the was described in, relation to conduit 10.
Fig 1, $olte 83 are provided for moving It will be noted that the tube the draw-ring g5 to the Left, 72, and which is present in the gooseneok therebx clamping the pips-spigotsof the torch, is electrically ~.nto the block 69. live;
as is conventional, a sleeve of At the service station as shown insulating material is slipped in aver Fig 1, the requirement, as far the tube 7~, and also a protective as s7.eeve of metal is provided outside the physical characteristics of tt~e insulating sleeve.
the components was concerned, was to support the conduit 10 in a secure, robust fashion, At the torch end of the conduit, on the other hand,Ir some alternative types of the requirements are different, welding torch, the water jacket in of that now the main requirement the torch is located radl,ally is outside the electrical insulation.
that the components should be An example i$ shown in Fig 7, light The in weight; the components also invention can still be put into should be physically small, practice in this case, but of especially as regards radial co~~rse the designer must see dimensions. As shown iri Fig 4, to i.t the th;~,t the metal parts of the shape of the block 69 is not simplywater circular, but includes Weight- jacket outside the insulator are reducing cut-sways 85. Similarly,isolated electrically from the the draw-ring 6S may be trimmed we7_ding current. This can be to done reduce the weight (Fig 5). by including shoat lengths of rut~ber tubing 89 (Fig 7) in the The components shown in Fig 3 wa~.er feed and supply pipes.
fit inside a plastic handle 87 (Fig 6) of conventional type, which is Generally, the connection between moulded in two halves. A trigger the pipe-spigot 67 arid the block is included in the handle, which,69 when operated, activates the has to be such that the connection transmits the feed or raturn water without leakage thereof; the 1=bread connection at that location connection has to be such as to be y~ould be unreliable, xhat is to electrically capable of fray: if the pipe-spigot were transmitting weld~.ng currents (zn f~ecured into the b.~ock by means of the hundreds-of-amps range); and a, acrew~threac3 connection, the the connection has to be screw-thread would be so small that mechanical~,y strong and robust, there would be a danger that the since the components are inevitably thread would strip, even with just subjected to spurious twists, a small degree of abu$e. It may be knocks, and other abuse. Tt ie noted also that the components ~,n preferred that the design of the question are generally made of connection ie such that, if a knock brass, which material has no great is so abusive that some failure r~3sistance to the stripping of occurs, that the failure takes the threads if ovextightened.
form of a bending of the spigot, rather than a rupture of the joint Moreover, the connection between that might allow leakage of the the pipe-spigot and the block must water. b~~ watertight, and it may be noted that it is difficult to make a A comparison may be drawn between screw thz~ead watertight. In the securing the pipe-spigots 67 into case of a welding torch the the block 69 by means of the requirement fox watertightness is tapered connections 80, as shown, especially demanding in that even with securing pipe-$p~,gots into a tiny drops of water leaking into block by means of screw-threads. the arc axea will spoil the weld.
because of the very tight restriction on the radial space when the connection between the envelope in the torah handle $7, pipe-spigot and the block makes use the room available for the spigot- of the plug and socket arrangement, to-block connection, whatever its with the pipe-spigots being drawn structure, is severely limited. It in-~o the sockets by the action of is recognised that if this small thce draw-ring, it will be space were occupied by a screw- understood that the above-described thread connection, the constraints problems of screw-threads are would be so tight that the screw-- largely alleviated. The draw-ring may be made of steel, and the .eadial apace at the service bolts station acting on the draw-ring are ~snd of the conduit, it is simpler also of steel, which gives good strength,1~o have components the same.

and in any case the draw bolt threads can be large and robust.~_t is contemplated that plug-and-It will be understood that evene;ocket connections, as described, the most vigorous abuse is hardly may be used in conjunction with the likely to strip the threads conventional screw-in connections.
of the Connection between the draw ~~hus, the pipe-spigots may be bolt arid the draw-ring, whereas connected to the block at the even torch alight abuse could strip the end of the conduit by means of threads in a corresponding spigot-connections as described, whereas to-block screw thread connection,at the service station end, the pipe-spigots axe connected by The connection as described s~~rewing the pipe-spigots into has good electrical properties. screw-threaded holes in the block.
When assembled, the pipe-spigot becomesI1: will be understood that the tightly wedged into the Socket,screw-thread connection should be which gives an excellent, large-me~de first, when the pipe can contact-area, electrical connectionrotate.

for the heavy welding currents.

Although two pipes have been Also, the connection as describedde~sCribed, more than two may be has good watertightnees properties.provided. The draw-ring and draw With the tapered-plug-in-socketbelt arrangement can be used td type of connection, the designertighten more than two pipe-spigots can easily specify the provisioninto place (simultaneously) into of an O-ring, which gives reliablesuitable.sockets.

watertightness.

Th~3 water jacket which is to be Preferably, the designer shouldsub?plied with cooling water may be make the pipe-spigots 67 at loi.ated deep inside the torch, the end service-station end identical as close to the tip as possible;
to the spigots 36 at the torch close, that is to say, both in and. the Although there is no premium radial sense and in the axial on sense. In the torch shown in the the total of water passageways as-mentioned EP-93/202,778.2, for xnnning along the conduit from the example, the water jacket is very s~arvice station to the torch 103 is c lose to the tip . f caur .
Alter~tatively, the water jacketF:Lg 9 is a continuation of Fig may 8, be located towards the outside and shows the handle of the torch of the torch, as the more or less 1(13. The non-live pipes 112,114 outermost component of the torch.are brayed into suitable sockets in Zn either case, the manner, as a block ring 116. The block ring described, of arranging the spigots11.6 defines a hollow chamber 118, may be utilised. when the water and the pipe 114 opens into this jacket is buried deep inside criamber, whereby the chamber the is torch, the water jacket is fL.ll of water. pn the right-hand electrically live; when the waterside of the block ring 1i6, a pipe jacket lies towards the outside 114a communicates With the chamber of the torch, the water jacket is 118. The other pipe 112 continues non-live, through the chamber 116. sy this arrangement, the block ring 116 Fig 8 shows a diagram of the serves as a supplementary tip area of a torch 103 which has circulating cooling jacket of two the water jackets: an inner water non-live cooling system, arid this jacket 105 which lies deep insidesupplementary jacket is suitably the toxah, and an outer water positioned, as shown, for Cooling jacket 107 which hzes towards the torah handle 120 itself.
the The outside of the torch, The inner torch handle comprises a plastic water jacket 105 is electricallymo~uldi.ng in two separate halves live, while the outer water jacket123a,123b.

107 is non-live. The inner water jacket 105 is furnished with This various services are conveyed a water-feed passage 209 and a fr~~m the handle 120 to the front water-return passage 110, and the outerenti of the torch 103 thrppgh the water jacket 107 is furnished gooseneck 125. The welding wire with a water-.feed pipe 112 and a 12'~ runs inside a plastic--covered water-return pipe 124 (Fig 10), wherebycak~le 129, which lies inside the tube 130, and the axgon, C02, or Holes 143 in the body 140 convey other gas is conveyed in the the gases around the tip 138.
tube A

130, around the cable 129. deflector 145 of ceramic material, ensures the gases do not jet The tube 130 is bxazed into directly onto the arc.
a tube 132, and the feed and return water passages 109,110 are formed The outer (non-live) water jacket as flats machined on the outer 107 lies outside a sleeve 147 surface of of tube 130, in the manner as insulative material. The inner tube described with reference to 149 of the outer water jacket Fig 4. is brazed onto the protective metal The tubes 130,132 are both sleeve 136, and the outer tube electrically live. Surrounding o the water jacket is brazed in the tube 132 is a sleeve 134 of turn onto the tube 149.
plastic insulating material. A metal sleeve 136 in turn surrounds T:he outer tube 150 of the outer the plastic sleeve 134, and serves w,~ter jacket 107 defines a to protect the sleeve 134. The cylindrical surface for receiving metal a sleeve is electrically isolatedshroud 152. The shroud is a push-from the tubes 130,132. f:it over the cylindrical surface, whereby the operator can slide the The welding wire 127 emerges shroud off (to the left in Fig from a 8) copper tip 13$, which in Fig t<> gain access to the tip 138 $ is --in two pieces 138a,138b. The fc>r the purpose, for example, tip of components 13$a,138b are screwedreaplacing the components of the into a body 140, which actuallytip.
is a continuation of the tube 130.

Flow directors, dividers, or It w~.ll be noted that the inner baffles (not shown) placed inside {live) water jacket 105 overlies tree Water jacket cause the water to the tip components; by extending so circulate around the water jacket fair forward, the inner water jacket in. an advantageous manner.
can be very effective at keeping the tip cool-running, even under Fig 11 shows a cross-section of a very heavy welding duty. block 156, in which are located two Pipe-spigots 158,159. The spigotsThe spigots 158,159 axe connected are arranged in a similar mannerto water electrical to hoses in relation that illustrated in Fig 3. (ln and 165 (Fig Fig l~bads, 9) 9, it will be understood that as was these two the described the pipes Pipe spigots are present, but t~~ Fig 112,114 lie 4. The of out of sight.) The spigots 158,159conduit electrical are clamped into tapered holes contains in not only the black 156 by means of bolts h~5ses/leads 160 but also 1.12,114.
(The pipes course do not contain and draw-ring 153, in the mannerIc~ads.) as previously described.

A:Lso within the conduit is the Space inside the handle 120 is hosepipe 167 which surrounds the tight, and the block Z5fi is cut aeible 129. This central hoeepipe away, as shown in k'ig 11, to 1f~7 is generally of greater provide room for the pipes 112,114 da.ameter than the four water-for the outer water jacket. ccmvey~.n,g pipes, and its larger Cutting away the block not only stiffness can affect the gives access room, but also ma.nipulability of the conduit and lightens the weight of the block. torch. Therefore, it is The designer should see to it, as a advantageous to provide a swivel general principle, that the joint 169 (Fig 9) for connecting component9 of the torch and the the central hosepipe lfi7 into the handle are as lightweight as handle 12p.
possible. The draw-ring 163 similarly is cut away as shown in As shown in Fig 9, the inner tube Fig il. 130 is formed, at ,its handle-end, with a cylindrical socket 170- A
Since the pipes X12,114 are non- boss 172 is provided on the outside live, whereas the block 156 is of the socket 170, which houses a live, the designer should ensure grub-screw 173. A hollow stud 176 'that the sleeves of plastic fi-is inside the socket 170; a insulation are fitted over such groove in the stud z~eceives the portions of the pipes which may be grab-screw 173, whereby the stud of metal,, and which may contaot the 17~i may be clamped firmly into the block. svc:ket 170.
lz A rotor 17B i,s clamped into ~,nd even if some gas were to the escape hosepipe 167, and engages the i,t would do little harm (apart stud from 176 in such a manner that the the cost of the lost gas). Such rotor inconsequential leakage of gas is rotatable relative to the may stud. be contrasted with the consequence A sleeve 180 is swaged to the of a leakage of water from the stud water jackets, in that if water 176, and retains the rotor to the stud, as shown in Fig g, droplets get into the weld they When the conduit 165 is being can be very damaging.

Called upon to tWlgt relative tp the handle 120, a degree of swivelI:~ order to release the pipe of the central hosepipe 167 can,s~?igots 158,159 from the block by 156, means of the swivel-joint 169, f~~r sexvicing of the torch, it take is Place. The stiffness of the nEacessary for the draw-ring 163 central hosepipe was the largestto contributor to the whole stiffnessmove to the right (Fig 9~.
of the conduit; the other pipes However, the boss 172 might and interfere with such free movement hoses in the conduit, being of: the draw-ring. As Shawn in relatively small, have not much Fi.g 11, the draw-ring is C-shaped inherent stiffness, arid not a complete ring, whereby tr.e draw-ring can pass over tt~e It will be noted that the weldingbass 172.

gas passes inside the hose 167 and inside the tube 130. Therefore, Fig 12 is a view, like Fig 11, the swivel-joint 169 should be of a designed so as not to leak. It manner of arranging the components is inside the handle of the torch, recognised tk~at the leakage where space is much confined.
of gas The can be kept to a low enough valueblsck 174 is shaped in its upper as to be insignificant when the ar~sa with suitable cat-outs to swivel design is as shown. Iri provide room for the pipes 112,114 the su~aplying the outer water jacket.
design as shown, no elastomexic seals are required, as the leakageThe spigots 67 through which water path for gas passing out throughis supplied to the inner water the joint is tortuous enough, ja<:ket are clamped into the black in itself, to give an adequate seal.17~E by means of the draw-ring 176.

The draw--ring is of complementaryevenly -- obviously, it would shape to the block 174. Three be bolts 178 are used to force the possible to damage the spigots draw-ring towards the block. by At uneven tightening. However, again least one of the bolts should j.t may be noted that the draw-ring be amd the bolts are of steel, and threaded into the draw-ring, are and themselves highly resistant to have its head protruding on the being damaged: the contrast to remote side of the block, so other welding torches, where scre~,,_ that, threads are provided in small when the bolt is slackened, a brass blow components again needs to be made.
on the head tends to separate the draw-ring from the block. This is required because of the fit of Fig 13 shows another drawl,ng the of a spigots into the block, which torch handle, which illustrates preferably is a selfwlocking-taperhow f~.t. Knocking the draw-ring the components as described can and be the block apart: releases the a~-ranged to fit inside the handle, self- Ii: will be noted that the block lacking taper. only one of the can bolts need have this accessibilitybf! arranged to Iie behind the to be knocked: the others may, area if of the handle which houses the more convenient, be threaded electrical trigger 180, whereby into a the block, with the heads slim, efficient, design can be maintained.

contacting the draw-ring.

Of course, the designer of the Tn all the designs, the designertorah which has both an inner seeks tv arrange the draw-ring, (live) water jacket and a separate and outer (non-live) water jacket the bolts, so that a balanced is force fared with the most demanding can be applied to the pipe spigotsrequirements ~- given that the when drawing the spigots into conduit has to be lightly the respective blocks. In Fig 2, just one bolt was provided, Figs 5 manipulable and yet physically and robust; and given also that the 11 show four bolts, and fig 12 to~:ch has to house two separate shows three bolts. When servicingwager systems and still be light the torches, when these bolts anti compact. The designs as are illustrated show how these released, the technician should take care to clamp the bolts down demanding requirements can be p,s shown in Fi met. 12 i h g , n t e case where the torch has two water The designs as described providejackets, one live and one , excellent cooling of the weldingnon-live there , are a total of four .

torch, particularly of the very pipes tip present in the conduit 165, of the torch, and especially between the torch and the service so when the torch is fitted with centre. The pipes 112 and 114 two water jackets. The benefits of serve the non-live water jacket this excellent cooling are not (Fig 8), whereas the tubes 45 just serve that the torch is cool and the live water jacket 105.

oom:~ortable to hold, but rather, the cooler the tip of the torch,A torch with two water jackets i e the less 7.ikely it is that the , , a non-live jacket outside the welding wire might weld itself insulation, and a live jacket (eg, upon switch-off) to the tip inside the insulation, has components. Also, the build-up excellent performance of and can debris inside the front of the , operate continuously at heavy torch is less of a problem if current levels for a long period the of tip is running cool, because time, if required.
the debris dyes not then adhere to the components of the tip. However, although the provision of tt~ie twp water j ackets is These latter benefits of cool aclvantageaus, it can be troublesome running are useful even if the to provide for the presencE of four torch is not held in the hand pipes in the conduit. Also, it --- if can the torch is held in a robot bE troublesome to provide two arm, for example. water-circulation-pumps (and associated components) at the The two water jackets, where service station.

provided, are useful because of the presence of insulation in the As will now be described, it can be torch, whereby cooling inside arranged that the two separate the insulation is not transmitted water jackets may be served, using outside the insulation, and viceonly two (i.e not four) water pipes versa. in the conduit, connecting between the torch and the service station.~~he pipe-stubs align with the pipes Fig I4 shows the arrangement. ,12,114, and are connected The therewith by means of short lengths arrangement not only permits of rubbex hose x,95.
the designer to get by with two water pipes instead of faun, but it C~n its right side, the block also 190 is eliminates the need for the extraformed with tapered connections pump. In Fig 14, the same water 197 is for receiving pipe-spigots 1.98,199 used sequentially for both waterof the kind which have been jackets, the water passing aroundpreviously described. The two the inner jacket first, and thenpipe-.spigots are coupled to in r~aspective flexible (plastic) series around the outer jacket. water p:Cpes which run along the J.ength The arra~ngernent of Fig 14 has of similarities to that of Fig 9, the conduit and connect with the in service station. The electrioai that the inner, live, water-jacketec~nnection to the torch is via 105 is fed, in Fig 14, vza the f7.exible leads located inside water-feed and -return passages the 109,110, which are in the form w~~ter pipes.
of flats cut on opposite sides of Water from the service station the enters the block 190 through the wall of the tube 130. Also, the spigot 198. From there, the water outer, non-live, water-jacket travels inwards along a drilling 107 200 (which is blanked off by means is fed via pipes 112,1,14, whichof a brazed.-in plug 202), through axe th~~ aligned hole in the metal secured into the block ring 116,tube as was described with reference to Fig 13a, and into the water-feed In place of the block 156 of pa~3sage 109.
Fig 9, with its straight-through passageways, the rathex more From there, the water passes around complicated block 190 is used. thE~ inner water jacket 105. The On wager returns along the passage its Left side, the block 190 11t~. Upan returning to the block is 19U, the water then travels formed with respective sockets outwards along a drilling 204, for and receiving two pipe-stubs 192,193, which axe brazed into the sockets.

into the stub-pipe 193 and pipe 7.09,110 for the inner jacket.
114.
There are no straight-through water From there, the water circulates connections in the block 190 (as around the outer water jacket 107. they were in Fig 7). The cross, The water returns along the pipe drillings, hole-plugs, connecting 112, and re-enters the block 190 passages, etc, inside the block 190 through the stub-pipe 192, are such as to conduct the water first through the inner jacker and The direction of the water flow may then through the outer jacket, in be reversed, i.e the water may be series. The skilled expert can, ~.n directed to flow first through the a particular block, trace the outer jacket. p,~ssageways required to achieve the d~?sired water--f low patterns .
Inside and within the block 190, the stub-pipe 192 is connected to Tlxe block 190 preferably is made of the spigot 199. This connection is brass, and the plugs are brazed made by means of a series of cross- into the drilling as required; as a drillings, blanked,aff passageways, general rule in welding torches, and the like -- the exact nature of the use of rubber seals should be which depends on the specific at~oided except where the sealed dimensions and layout of the actual components have to be detachable.
black 190. The connection is shown in d~.agrammatic form in Fig 14 by In. addition to the water-conveying the dot-dash line 206. passageways in the block 190, the designer must see to it that the It will be understood that the block also contains holes for block 190 thus has two pprts facing attaching the screws which pull the to the right, into which are draw-ring 208, and the spigots, insexted the two spigots 198,199; into the block, in the manner as but the block has tour ports facing px~sviously described.
to the left: namely the two sockets into which are inserted the two Th~~ block I90 is electrically live, stub-pipes 192,193 for the outer be:zng put in circuit with the wires jacket, and the two passages xn~3ide the water pipes in the conduit by means of the tapered connections 197. The stub-pipes are electrically isolated from the block ring 116 (and from the outer water jacket) by means of the rubber hoses 195 (one of which is omitted in Fig 14).
Although there is a water connection between the two water jackets, there is little leakage of electrical current to the non-live water-jacket components, provided the water remains reasonably clean.
flf course, the metal stub pipe cannot be connected directly td the black-ring 116.
Electric current is supplied to the block 190 thxough the spigots 198,199, which are connected to the flexible electrical current conductors as previously described.
For clarity of illustration, as will be understood by the skilled expert, the torches in the drawings are shown with their radial dimensions exaggerated. zn fast, the designer should see to it, that the radial dimensions are as small as can be, bearing in mind the need for robustness.

Claims (8)

Claims
1. CLAIM 1. Fluid-cooled welding torch apparatus, wherein cooling water or other fluid coolant is supplied and conveyed from a service centre to the welding torch, wherein:
   the apparatus includee a block, which has an interior block coolant-passageway;
   the apparatus includes a pipe spigot which has an interior spigot coalant-passageway;
   one of the block or the spigot has a socket, having an axis, and the other hoe a complementary plug, which ie axially engageable therein;
   the apparatus is so arranged that when the plug is operatively engaged in the socket, the block coolant-passageway communicates with the spigot coolant-passageway;
   the apparatus includes a collar which is arranged, in the apparatus, to be axially moveable relative to the block;
   the collar is in operative engagement with the spigot, to the extent that movement of the collar towards the block is effective to create a corresponding, in unison, movement of the spigot towards the block;
   the apparatus includes a screw-threaded fastener, which is arranged so that tightening thereof causes movement of the collar axially towards the block, whereby the spigot is moved axially towards the block, and whereby the plug is urged into the socket; and the plug comprises a conically-tapered plug-form on the spigot, and the socket comprises a correspondingly conically-tapered socket in the block.
2. Claim 2. Apparatus of claim 1, wherein the conically-tapered plug-form is of such taper-angle as to be self-locking.
3. Claim 3. Apparatus of claim 1, wherein:
   the collar includes a through-recess, which is a clearance fit over the spigot;
   the through-recess ie not completely enclosed, but is open laterally, whereby the spigot can be laid in the through-recess in a lateral direction.
4. Claim 4. Apparatus of claim 3, wherein:
   the spigot is formed with two abutments;
   the two abutments are so spaced that, when the spigot ie laid in the through-recess in the collar, the abutments abut respectively both sides of the collar;
   whereby movement of the collar in the axial direction, and in both senses of that direction, is effective to cause axial movement of the spigot.
5. Claim 5. Apparatus of claim 4, wherein:
   the screw-threaded fastener is threaded into the collar, and passes through a clearance hole in the block;
   the screw-threaded fastener is a bolt having a head which lies on a side of the block remote from the collar; and the arrangement of the block, collar, spigot, and screw-threaded fastener is such that, when the fastener is slackened, a blow on the head of the bolt is effective to drive the plug out of the socket.
6. CLAIM 6. Fluid-cooled welding torch apparatus, wherein cooling water or other fluid coolant is supplied and conveyed from a service centre to the welding torch, wherein:
   the apparatus includes two pipe spigots, each of which has a respective interior spigot coolant-passageway;
   the apparatus includes a block, having two sockets with respective parallel axes, into which respective plugs of the spigots are axially engageable;
   the apparatus is so arranged that when the spigots are operatively engaged in the block, coolant-passageways on the block communicate with the respective spigot coolant-passageways;
   the said spigots are connected to respective flexible hoses or pipes, within which the coolant is conveyed, one to, and the other from, the torch;
   when engaged in the block, each spigot is in electrical current-transmitting contact with the blank;
   the apparatus includes electrical current-conveying-means, for conveying electric current from the service station to the welding arc;
   
   the current conveying means includes two flexible leads, which are located respectively inside the two flexible hoses or pipes, and each lead is in electrical current-transmitting contact with the respective spigot.
   the apparatus includes a collar which is, arranged, in the apparatus, to be axially moveable relative to the block;
   the collar is in operative engagement with the spigots, to the extent that movement of the collar towards the block is effective to create a corresponding, in unison, movement of the spigots towards the block;
   the apparatus includes a bolt, having a screw-thread;
   the collar includes a correspondingly screw-threaded hole, and the bolt is threaded into the collar;
   the bolt passes through a clearance hole in the block;
   the bolt has a head which lies on a side of the block remote from the collar;
   the apparatus is so arranged that tightening the bolt causes movement of the collar towards the block, whereby the spigots are moved towards the block, and whereby the plugs are urged axially into the sockets.
7. Cisim 7. Apparatus of claim 6, wherein the arrangement of the apparatus is such that the electrical current is split substantially evenly between the two flexible leads.
8. Claim 8. Apparatus of claim 6, wherein:
   the torch includes an insulative sleeve;
   the torch includes an inner, live, coolant jacket which is located inside the insulative sleeve, and which, in operation of the torch, is electrically live;
   the torch includes an outer, non-live, coolant jacket which is located outside the insulative sleeve;
   the block is formed with first passage means for conveying coolant received from a first one of the said two pipe spigots to and around a first one of the coolant jackets, and for receiving coolant returning from the said first coolant jacket;
   the block is formed with second passage means for conveying coolant received from the first coolant jacket to and around the second coolant jacket, and for receiving coolant returning from the second coolant jacket;
   and the block includes means for conveying that returned coolant to the other one of the two pipe spigots.