VОRRIСНТUNG ZUМ SСНWЕISSЕN ЕINЕR DRАНТGIТТЕRМАТТЕ

The invention concerns a device for welding a screen mat from each other right-angled crossing Längsund transverse wires, with Oberund Unterelektrode. An older proposal concerns a blower for cleaning the welding electrodes of a lattice welding machine. Here cleaning air is supplied directly by the Schweil$elektroden. This mechanism has the disadvantage that only particularly made electrodes can be used and that the impurities are not sucked off, but are not blown into the welding line. With single place welding stations it is well-known to suck the welding smoke off by suction trunks which are attached in the range of the job of the welder. A cleaning by compressed air is not intended, there the intermittent function with changing, too verschweil ends to workpieces this not required. Task of the invention is it to avoid the described disadvantages and to create a device of the introductory indicated kind, it made possible to ensure a safe and clean contacting of the wires with the welding electrodes and when welding developing impurities, how e.g. burn-up to suck welding smoke off. The device according to invention is characterised by that for cleaning Oberund Unterelektroden with cleaning air a blower are intended, whose blow-out port hands if possible close into the range of the welding positions Längsund of transverse wires, and that for sucking cleaning air and the impurities off a suction mechanism with at least a suction nozzle is intended, to whose entrance opening if possible close is enough into the range of the welding positions. Preferably the blower exhibits at least a Blasrohr for each welding position, which is stationarily in such a manner arranged that its blow-out port hands if possible close into the range of the welding position, and that the air supply of the blower is controllable. After a further characteristic of the invention the suction mechanism exhibits for each welding position a suction nozzle, whose entrance opening within the range of the welding position begins and to which in all suction nozzle flows to common withdrawal duct, whereby the suction mechanism exhibits, a controllable suction unit existing made of filter and fan. Further characteristics and advantages of the invention are more near described in the following with a remark example with reference to the design, which shows a schematic side view of one erfindungsgemäl EN device. The represented device finds use in a resistance lattice sealing machine for making screen mats of each other right-angled crossing longitudinal wires L and transverse wires Q, whereby several longitudinal wires L are supplied to each other parallel and together with lateral distance along the longitudinal wire level JE-E according to the direction of arrow P1 and the transverse wires Q are put down right-angled to the longitudinal wires L on these in the welding position S and welded with the longitudinal wires L. The surface of the wires L, Q can exhibit smoothly or, as usual with reinforcing steels, a serrated surface. The moreover one the surfaces of the wires can be provided with a zinc layer brightly or with an oxide layer or. The device exhibits an upper, hebund lowerable Eiektrodenhalter 1 and a lower electrode holder 2, which are underneath the upper electrode holder 1 and below the longitudinal wire level E-E arranged and preferably stationary. Within the framework that. Invention is however also possible it, which lower electrode holder 2 likewise hebund lower, to implement bar. At the lower end the upper electrode holder 1 an upper electrode 3 is arranged and at the upper end of the lower electrode holder 2 a Unterelektrode 4. The Obereiektrode 3 and the Unterelektrode 4 are disk-shaped trained and have the form of a polygon, for example an octahedron. According to invention the upper electrode 3 at their extent can exhibit a transverse wire groove, which serves is trained V-shaped for the admission of the transverse wire Q when welding, and is adapted to the dimensions of the transverse wire Q. Also the Unterelektrode 4 can exhibit verlaulende longitudinal wire groove, which serves is trained Vförmig for the admission of the longitudinal wire L when welding, and is adapted to the dimensions of the longitudinal wire L in the context of the invention at everyone Flut of the polygon one parallel to the longitudinal wire level E-E. In the context of the invention it is furthermore possible, also different arranged Oberund Unterelektroden to use as well as other forms for dieQuerund Längsdrahtnllen, adapted to the cross-sectional shape Querund of longitudinal wires. The current supply of the upper electrode holder 1 takes place with the help of a bond 5, which intersperses RK 411,738 B the longitudinal wire level E-E and exhibits within the range of the longitudinal wires L appropriate passages for these. The bond 5 is connected with a flexible current volume 6 with the upper, mobile electrode holder 1. The device according to invention exhibits a blower 7, which consists of at least approximately parallel to the longitudinal wire level E-E a running Blasrohr 8 and is intake-laterally arranged in production direction P1 seen before the welding position S. The Blasrohr 8 is screwed with the help of an attachment 9 stationarily onto the bond 5 and hands with its blow-out port 10 as close to the welding position a S as possible near. In the context of the invention two Blasrohre can be used, which are fastened to both sides of the bond 5. In lo the context of the invention the Blasrohre can be fastened also to another part, which is present in the range of the welding positions. The blow-out port 10 is in such a manner arranged that withdrawing cleaning air possible with high air-flow pressure on the work surfaces of the Schweil - electrodes 3; 4 hits. Particularly favourably are here a close, oblong slot or a small, round air duct. During a schlitzförmigen blow-out port 10 the slot runs parallel is too the surfaces Oberund Unterelektrode 3; 4. The blower 7 is connected by an inlet 11, a control valve 12 and a service unit 13 with an air supply 14. As cleaning air compressed air is usually used. In the context of the invention it is possible, also different technical gases to be e.g. used as nitrogen for the cleaning. At the discharge side of the welding position S a suction mechanism 15 is arranged below the longitudinal wire level E-E, which exhibits for each welding position S a suction nozzle 16. The entrance opening 17 of the suction nozzle 16 hands as close to the welding position a S as possible near and is so grol selected that the impurities blown away by the blower 7 and cleaning air can be absorbed surely. The suction nozzles 16 run diagonally downward and flow in a common withdrawal duct 18, which runs transverse to the production direction P1. Over a return pipe 19 the exhaust air of a suction unit 20 from the withdrawal duct 18 consisting of filter and fan is sucked off and the cleaned exhaust air over an exhaust air duct 21 in the free is discharged. In the context of the invention it is possible to arrange the suction nozzles in such a manner that only one suction nozzle is used, which extends over the entire work width the lattice tail plant and flows into the withdrawal duct. In this case the suction nozzle consists of two parallel sheet metals, which are locked laterally. In the context of the invention also existing cover plates within the range of the welding positions can, like e.g. Cover plates of the welding transformers, in such a manner to be transformed that they can function as suction nozzles. As filters all commercial mechanisms can be used, which are able to separate the impurities like e.g. a cyclone for the coarse separation of particles and a fine filter downstream for separating dust and welding smoke. The device according to invention works in the following ways: After supplying and placing of the transverse wire Q on the longitudinal wires L in the welding position S the upper electrode holder 1 with the upper electrode 3 so far lowered to the upper electrode 3 on the transverse wire Q rests upon. Shortly before lowering the upper electrode 3 cleaning air and the exhaust are switched on, whereby any impurities are blown away if necessary if necessary first particularly of the Unterelektrode 4 and by their longitudinal wire grooves and during approach of the upper electrode 3 also by this and by their transverse wire grooves by cleaning air and sucked off over the suction nozzle 16. The air supply and the exhaust remain during the following welding procedure as well as still some time after completion of the welding procedure during the Abhel0ens of the upper electrode 3 in enterprise. This Nachblasen is particularly important, since the impurities can be blown away and sucked off only with taking the upper electrode 3 off and thus relieving and slight taking of the longitudinal wires L off from the Unterelektrode 4 effectively. In the context of the invention it is also possible, cleaning air above as to be steered descriptive and to constantly operate the exhaust during the period of operation of the Schweißvordchtung. In order to keep the control expenditure small, it is further possible in the context of the invention to constantly blow and constantly suck off during the period of operation of the welding jig with cleaning air. Increased Reinigungsluftund energy consumption is to be placed here to the possible saving of a control economically opposite. RKs 411,738 B depending upon surface finish of the wires can get the surface dirty of the welding electrodes 3, 4 with the Verschweil EN of the wires burn-up, welding splash, scale remainders, drawing central remainders, zinc steams etc. Erflndungsgemäl the e device has the advantage that the work surfaces Oberund Unterelektrode 3, 4 and any Querdrahtund longitudinal wire grooves in the work surfaces are kept free by impurities and thus the quality of the welded joint remains even by the avoidance of these impurities and in addition the service life of the electrodes is increased. Aul the entire welding range of the sealing machine is kept by purposeful sucking of the impurities and in particular the welding smoke off clean to erdem. It understands itself that the represented remark example can be modified in the context of the general Erflndungsgedankens occasionally, in particular regarding the arrangement and execution of the blower and the Absaugeindchtung.