Device for guiding rounded borders through a welding zone.

The invention relates to a device for passing rounded sides by a weld zone of a machine for welding the longitudinal edges of the sides, with groups of movable guide elements each with respect to the opposite sides and thereby exercise radial executives.

In known devices of this type (DE-PS 25 59 671) are round, arranged as guide elements diabolo-like rolling around the axis along which move the frames. Some of these roles is such radially resiliently supported, that they exert on the sides forces who are eager to push their longitudinal edges against a stationary guide Schine of Z-shaped profile. Such movable only in the radial direction and rotatable about a respective own axis guide members serve their purpose properly, if the sides, which are passed through the weld zone, have a diameter on the order of 50 mm or more, especially when the longitudinal edges of the frames in a overlap-pinch are welded. However, problems can occur with known devices of the type described, when the Zargendurchmesser is less than 50 mm and / or the longitudinal edges of the frames are butt-welded together, in particular by means of laser beam. In such cases, the quality of the weld can be reduced by almost imperceptible shocks, each occur when one of the numerous arranged in or near the weld zone roll-shaped guide elements rolling only on the front and later on the rear end of a frame.

The invention is therefore based on the object to design a device for passing rounded sides by a welding zone such that it is also suitable for frames of small diameter, for example, 32 or 25 mm and in particular for laser welding of the longitudinal edges of such frames. Sides such small diameter are needed especially electrical property batteries.

The object is achieved in a device of the kind described above according to the invention that the guide elements of each group are arranged on an endless chain, which has a running in the direction of movement of the frames chain strand, the both sides of one containing the welding zone, normal to the direction of the sides level, the welding plane, is supported by a rail.

Although it is a transportation system for can bodies in resistance welding machines known (DE-OS 28 10 188), are arranged in two bumpered cammed carriers chains succession, of which a chain passes through a station for rounding of frames in which they the while rounding sides temporarily at least approximately stationary, while the second chain adjoins the first chain and from the rounded sides takes over, to move it to the weld zone. However, the second chain ends at a distance upstream of the welding plane; it leads the rounded sides not but push them forward only until they are detected by two electrode rollers and further promoted by these. For passing the frames through the welding plane independent calibration tools are from the chains provided that, as described above, interact with diabolo-like rolling on the sides and not take part in their conveying movement.

Contrast is achieved with the invention that the guide elements, while exerting the necessary radial executives on the sides to work together through the welding plane move therethrough and thereby supported on both sides of the welding plane, ie conveyor upstream and flow down from it to the associated rail , This collisional impacts are avoided on the sides near the welding plane; the longitudinal edges of the frames move consequence calmly and evenly through the weld zone through.

Preferably, each of the rails extends without interruption and in a straight line between a beginning and an end, the distance from the welding plane is greater than the length of each individual frame.

It is also advantageous if the guiding elements are attached to each two hinge pins of the associated chain.

It is also expedient if the guide elements each have a cylindrical bearing surface for the sides.

The chains are preferably constructed as roller chains and supported via their roles on the associated rail.

It is conceivable that the sides are, for example supported in a known manner by means of reciprocating driver, are conveyed through the welding plane or only up to the welding plane, and then moved further away from electrode rollers. In such cases it is possible in principle substantially frictionless guiding and deflecting the chains that the chains are not self-propelled and are simply taken from the frames.

In a preferred embodiment of the invention, however, the chains wrap around a respective drive wheel, via which they are driven.

This preferred embodiment is advantageously further developed in that at least one of the chains together with the associated rail and a Kettenspannrad around the associated drive around can be pivoted away from the opposite chain. In this way, the inventive apparatus for maintenance and for eliminating interference can be easily opened.

It is further advantageous if each of the rails on two springs is radially supported, the offset from one another in the conveying direction and are independently adjustable. This adjustment can be achieved in a particularly a number of ways that the longitudinal edges of the frames in the weld zone have each other a precisely predetermined position with respect to so either overlap by a certain amount when a Overlap weld to be produced or the longitudinal edges dull abutting when, in particular with a laser beam, a butt weld is to be formed.

In a longitudinal center plane of the device according to the invention may be as usual, is arranged a the longitudinal edges of the sides leading guide rail, in particular a rail with Z-shaped profile, commonly referred to as a Z-rail. It is advantageous if, according to another feature of the invention, the slide towards a the sides diametrically arranged additional leading magnetic rail.

Finally, it is advantageous if conveyor upstream from the chains a guide sleeve is arranged in a funnel shape tapering in the direction of movement of the frames and minde least one axial slot along which a latch to insert the frames between the chains is movable.

An embodiment of the invention will be described below with reference to schematic drawings in greater detail. It shows:<ul><li>Fig. 1 shows a device according to the invention in top view,</li><li>FIG. 2 shows the same device in a partially disassembled state and partially in a horizontal section,</li><li>Fig. 3 shows the section in the vertical plane III-III in Fig. 1,</li><li>Fig. 4 shows the section in the vertical plane IV-IV in Fig. 1,</li><li>Fig. 5 shows the section in the vertical plane VV in Fig. 1 and</li><li>Fig. 6 shows the device in one of the Fig. 1 corresponding plan view, but in the open state.</li></ul>

The device shown has the task cylindrical about an axis A rounded sides 10, which consist for example of uncoated sheet steel or tin plate to lead such that their longitudinal edges 12 and 14 firmly against one another can be welded together while the ribs 10 along its axis a forward, 1 and 2 are moved from left to right, by a normal to the axis a welding plane B in FIG.. Such welded housing are provided in particular as a housing for electric batteries.

The ribs 10 are, before they reach the device illustrated, was rolled from a round device of conventional design to a fixed lower arm 16 around, parallel to the horizontal in the usual way axis A extending through a likewise stationary guide sleeve 18 and the center represented the device protrudes. In the conveying direction of the frames 10 downstream of the guide sleeve 18 20 is fixed by a Z-shaped profile on the lower arm 16 is also a common guide rail, on which the longitudinal edges 14 and 16 of the sides are out. The guide rail 20 ends shortly before the welding plane B, in which a laser gun 22 is arranged, whose beam 24 is indicated in Fig. 4. In the area of ​​the beam 24, the longitudinal edges 12 and 14 running between a front end portion 26 of the lower arm 16 and, arranged on this slide shoe 28 passes, both of which are perforated so that they do not obstruct the beam 24th Vertically below a cooled absorber 30 is disposed.

To be pushed through the frames 10 through the guide sleeve 18 a pawl 32 is provided which is by means of a not shown conventional drive mechanism, for example of the type of a crank mechanism, parallel to axis A reciprocable and each in its forward movement by an axial slot 34 the guide sleeve 18 projects into the interior. Each frame 10, emerging from the guide sleeve 18 is detected by two groups of guide elements 36, which are arranged on a respective endless chain 38th

The two chains 38 are symmetrically arranged in the operating position of the device with respect to the axis A, each have a parallel to this forward-running strand of chain and extending in a horizontal plane around a respective drive wheel 40 and one Kettenspannrad 42. From the chain tensioning wheels 42 from converging the chains 38 to its axially parallel chain strands out.

In the example shown both chains 38 are formed as a triple roller chains; their limbs are interconnected by hinge pins 44, on each of which three rollers are mounted 46th Each of the guide members 36 is fixed to two adjacent hinge pin 44 and has a cylindrical bearing surface 48, whose diameter coincides with the outer diameter of the sides 10th

Each of the frames 10 is in the illustrated Zargenlänge on both sides covered by three guide elements 36 and along the axis A passes through the welding plane B. On the last of the three guide elements 36, a driver 50 is attached. The driver 50 at the two axially parallel chain strands are facing each other in pairs, so that each frame is 10 of a pair of drivers 50 which bears against its rear end is detected and thus also moved through reliable through the welding plane B when the radial forces, with where the guide members 36 act on their contact surfaces 48 on the sides 10, should be too weak to generate sufficient frictional forces to take away the sides.

The magnitude of the radial forces referred to is determined by the straight chain strand of each of the two chains is 38 supported on a rail 52nd Each of the rails 52 has three parallel to the axis A superimposed guide ribs 54, on which the rollers 46 of the associated chain run 38th The length of the guide ribs 54 upstream and downstream of the welding plane B is greater than the Zargenlänge; Consequently, each frame 10 on the accompanying guide members 36 from a time before the front end of the frame the welding plane B achieved, performed without vibration to a time, after its rear end has left the welding plane.

Each of the two rails 52 is slidably guided between two slide plates 56 which are each attached to a cheek 58th In each of the rails 52, two threaded bolts 60 are screwed, which extend in a horizontal plane radial to the axis A and are guided in a support 62 which is fixed between the two associated cheeks 58th Between each of the two rails 52 and the associated support 62, two compression springs 64 are clamped, which are arranged around each one of the threaded bolt 60 and the support rail with a supporting force on the order of for example 25 to 30 kg. In this manner, the axially parallel chain strand of each of the two chains 38 is adjustably supported by the associated rail 52 in a radial direction with respect to axis A.

In the vicinity of the rails 52 is a further support of the respectively associated cheek 58 66 attached to the the associated Kettenspannrad 42 displaceably guided and is also supported via a pressure spring 68th

The two drive wheels 40 are attached to each of a vertical shaft 70 which is mounted in a respective sleeve 72nd The two bushings 72 are mounted on a common, stationary baseplate 74th The two pairs of associated cheeks 58 are mounted on 70 each of the two shafts so that they can be pivoted about the associated shaft from their 1 to 5 shown in FIG. Operating position away from one another in a maintenance position.

In Fig. 6 is a pair of cheeks 58 together with associated apparatus parts, particularly chain 38 including guide members 36 and Kettenspannrad 42, pivoted to the service position, while the other pair Wangen 58 including associated device parts still occupies its operating position. On the upper cheek 58 of the two cheeks couples a lock plate 76 is attached to which a tie rod is mounted 78 pivotally. On the upper cheek 58 of the other pair cheeks a lock plate 80 is fixed in a corresponding manner, the one can be in the operating position of the device by means of the tie rod 78 and on this screwed Schraubgriffs 82 clamp together with the lock plate 76th The distance that the axis-parallel chain strands of the two chains 38 meet each other in the operating position is determined by an adjustable stop screw 84 which is screwed into the lock plate 80 and abuts with one of its faces against the lock plate 76th

The two shafts 70 are driven in opposite directions by exactly the same speed; For this purpose, a controllable electric motor 86 is connected via a pinion 88 and a toothed belt 90 with two gears 92, 70 which are mounted on each one of the shafts. The toothed belt 90 is wrapped around in addition a deflection wheel 94 which is mounted on the base plate 94th

In the drawings shows how the four frames 10 in succession through at fixed intervals the bechriebene in the preceding device and are guided by the guide elements 36 to the axially parallel chain strands. In the weld zone, the longitudinal edges 12 and 14 are welded to each other by the beam 24th The finished welded bodies 10 are then conveyed further between the axis-parallel chain strands and finally discharged at a relatively large distance from the welding plane B, for example, to a further-processing device.

To improve the guidance of the 10 frames even further, below the slide 20, a magnetic track 96 is mounted on supports 98th The ribs 10 slide in a longitudinal edges 12 and 14 diametrically opposite area on the magnetic track 96, before and while they are covered by the guide elements 36th This ensures that the frames 10 exactly occupy a predetermined position with respect to the guide elements 36th The magnetic strength is selected such that the frictional force between each frame 10 and the magnetic rail 96 with the sum of the frictional forces between the longitudinal edges 12 and 14 and the slide rail 20 matches at least approximately. Thus, the moments of these frictional forces are at least anähernd in equilibrium and can the frame 10 therefore not tilt.