DE212004000005U1 - Sensor arrangement for detecting the movement of a wire core in a welding system - Google Patents

Abstract

sensor arrangement for detecting the movement of a wire core (2) in a welding plant (3), through which wire core (2) a welding wire (11) between two wire feed devices (6, 9) led is, with one, the welding wire (11) surrounding sensor (1) with a housing (12) and an evaluation element (13), one formed by the wire core (2) or with the wire core (2) associated indicator (14) is provided, which indicator (14) in the sensor (1) in the longitudinal direction is displaceable force-free, and wherein the evaluation element (13) in casing (12) is arranged, characterized in that the wire core (2) directly into the housing (12) or through the Gehgäuse (12) of the sensor (1).

Description

The The invention relates to a sensor arrangement for detecting the movement a wire core in a welding plant, through which wire core a welding wire is guided between two wire feed devices, with a surrounding the welding wire Sensor with a housing and an evaluation element, wherein one formed by the wire core or indicator connected to the wire core is provided, which Indicator in the sensor in the longitudinal direction can be displaced force-free, and wherein the evaluation arranged in the housing is.

Furthermore, The invention relates to a welding system with a welding machine, a Hose package and a welding torch, wherein the hose package connects the welding torch to the welding machine, wherein between two wire feeders as a wire buffer memory formed device for buffering one within a wire core out welding wire and further including a sensor for non-contact measurement of movement the wire core is arranged.

In the welding technology The connection of the welding device with the welding torch usually via a Hose package in which all lines, such as a power line, cooling lines for a liquid cooled welding torch and one or more control lines are arranged. The one for one welding process needed welding wire is from the welder or, a Wire feeder so to the welding torch promoted by inserting it into a wire core. The wire soul becomes before threading of the welding wire in a wire guide hose inserted, which is preferably arranged in the hose package. there the wire core is preferably fixed at both ends, whereby no longitudinal movement is performed by the wire core.

Only with special wire conveying the wire core is arranged freely movable at one end. In the case of the systems known from the prior art, the wire core is arranged exposed in the area of the welding device or a wire conveying device and runs without guidance prior to the opening into the hose package. Specifically, such an arrangement of the wire core in welding wire conveyors with different Ge speed or conveying directions, ie a forward / backward movement of the welding wire, such as from DE 197 38 785 C2 or the DE 43 20 405 C2 known, used, in which case the exposed part of the wire core forms a kind of wire buffer memory.

For example, is from the DE 38 27 508 A1 a transport device is known in which a welding wire is conveyed even with unfavorable force effects with a constant force and thus tensile or compressive stresses are avoided. The welding wire is in this case between a sliding wire feed device which is arranged in the welding device or in a wire feed device, and a pulling wire feed device, which is preferably arranged in the region of the welding torch or in the welding torch itself, by an evading part and a curved hose, in particular the wire core. guided. The hose tension, ie the exposed part of the wire core, is supported by a spring. The evasive part is coupled to a control member which measures the evasion path of the evading part upon the occurrence of compressive or tensile stresses on the welding wire and supplies it to a controller for compensating via a speed control of the first drive. In this solution, the welding wire is unwound from the supply drum via the first wire feed device and inserted into a hose or a wire core. The wire core is then exposed and forms in this exposed area a wire buffer in the form of a loop, which loop can deform in this exposed area, ie the loop is enlarged or reduced. Subsequently, the wire core is inserted into the hose package and extends to the other wire feed over the wire guide hose, which is only slightly larger than the outer diameter of the wire core. The disadvantage here is that the wire core is rigidly connected in the form of a spring-loaded evasive element with an element for measuring distance. Another disadvantage is that a high disassembly and assembly effort is necessary when changing the wire core. In addition, it is disadvantageous that the welding wire in the region where it is preferably pushed, is not guided over a longer distance, which increases the risk of breaking the welding wire.

SU 1 489 941 A shows a sensor for detecting the capacitance of a wire buffer memory formed by a loop of the wire core, in which the wire core is arranged between two electrically conductive surfaces. By shifting the wire core is caused by a special shape of the surface, a resistance change from the position of the wire core within the sensor and thus on the capacity of the wire buffer memory can be closed. The disadvantage here is that the wire core between the surfaces of the sensor grinds and thus a force-free displacement of the wire core is not possible, which on the one hand adversely affects the sensitivity of the sensor but also adversely on the wire promotion. Furthermore, the sensor is subject to contact the wire core a higher wear. Finally, such a sensor, which extends substantially over the entire loop of the wire core is relatively bulky.

Furthermore, is from AT 394 675 B a wire feed device with a Along balancer described, wherein a sensor, the longitudinal movement of the hose package and outputs an actual value signal to a controller. adversely Here is that the longitudinal movement the hose package by means of a on a movable slide attached plunger anchor takes place. A disadvantage of this construction a sensor is the size and you relatively large moving Masses which a force-free displacement of the wire core in the sensor not possible power. This also reduces the sensitivity of the sensor.

A sensor arrangement of the subject type is for example in the JP 11028570 A described. In the JP 7246470 A , WO 02136296 A and the US 6130407 A Sensor arrangements for detecting the movement of a wire core in a welding system are also described.

The Object of the present invention is therefore in the creation a sensor arrangement for detecting the movement of a wire core in a welding system as well as a welding system the figurative Kind, in which a very simple and compact construction of the sensor is created. Another task is that the capture the longitudinal movement the wire core contactless done so as possible little disturbing influences in form of friction on the wire core and thus a very good Measurement result is achieved.

The inventive tasks are solved by that the wire core directly into the housing or through the housing of the Sensor extends. This is achieved in an advantageous manner that a direct path measurement of the wire core within the sensor assembly is made, whereby a very low susceptibility is given and thus the best possible Measurement results can be achieved. The closed unit prevents the ingress of dirt from the outside greatly reduced or prevented, so that the life can be increased can. Another advantage is that it achieves a very long gauge length Can be because the case of the sensor according to the expected length changes can be adjusted. It is also possible to change the size of the sensor very small, so that this directly in a welding torch or a hose package can be arranged. One major advantage is that that a simple replacement of the wire core without a previous Solve one rigid connection possible and thereby the service life of the welding system during which no welding done can, can be reduced. Due to the longitudinally non-displaceable indicator There are no frictional losses in the sensor, which causes the movement the wire core is not affected by the sensor. If the wire core directly into the housing extends, the indicator is located at the end of the wire core. When the wire core connected to the indicator passes through the Sensor extends through, the sensor can be anywhere be arranged the wire core.

advantageously, is the sensor in front of a wire feed device and preferred after a wire buffer storage located between the wire feeders arranged so that over the longitudinal movement the wire core the level or the storage volume of the wire buffer memory can be detected. This can be a simple and inexpensive way to monitor performed the wire soul movement become.

there the sensor is advantageously immediately in front of the wire feed device or immediately after the wire buffer.

If the sensor with an evaluation or a control device the welding system or connected to the welding machine is, the position of the sensor can be determined exactly.

advantageously, if the sensor is connected to a wire feeder, see above that the wire feed according to the level or storage volume of the wire buffer is adjustable.

Of the Due to the small size of the sensor in a welding torch, arranged in particular in a burner handle or in a hose package be. Thus, the size or Shape of the welding torch or the hose package is not changed by the arrangement of the sensor.

Of the Indicator can be fixed or detachable be connected to the wire core.

Of the Indicator can form the conclusion of the wire soul. In this case ends the wire core with the final indicator in the sensor. In this embodiment the sensor is thus arranged at the end of the wire core.

In the sensor can be arranged a discharge nozzle for the welding wire, whose inner diameter is usually only slightly larger than the diameter of the welding wire. The wire core thus can not austre through the outlet nozzle th.

According to one Another feature of the invention is that the outlet nozzle with the housing of the Sensors detachable connected is. This connection can for example via a According to one variant of the sensor is the indicator of ferromagnetic material and the evaluation element preferably of at least one electrical Kitchen sink.

alternative For this purpose, the evaluation element by a plurality of light sources, in particular Transmitting diodes and opposite photosensitive elements, in particular receiving diodes formed between which the wire forming the indicator or the indicator connected to the wire core is arranged.

As well Is it possible, that the indicator by a light-reflecting material and the Evaluation element by a plurality of light sources, in particular transmitting diodes with adjacently arranged photosensitive elements, in particular Reception diodes, is formed.

If the evaluation unit or control device in the housing of Sensor is arranged, a compact sensor arrangement can be realized become.

The inventive task is also made by an above-mentioned welding machine with one described above Sensor arrangement solved.

The The present invention will become apparent from the accompanying drawings, which embodiments describe the sensor, closer explained.

Show: 1 a schematic structure of a welding system in a simplified form;

2 a perspective view of a sensor with pulled-wire core;

3 a perspective partially sectional view of the sensor with associated wire feed device and inserted wire core accordingly 2 ;

4 a further embodiment of the sensor with pulled-wire core, in perspective view;

5 a perspective partial sectional view of the sensor with inserted wire core to the embodiment according to 4 ; and

6 to 12 a schematic sectional view of the sensor to illustrate different measuring principles.

In the 1 to 3 is a sensor arrangement, in particular a sensor 1 , for detecting the movement of a wire core 2 in a welding system 3 shown.

At the in 1 illustrated welding system 3 This is shown only schematically in the form of function blocks, which consists of a welding machine 4 in which a wire stock 5 or a wire reel and a first wire feed device 6 is arranged, a hose package 7 with integrated wire buffer 8th , another wire feed device 9 and a welding torch 10 consists. The in the welding machine 4 arranged wire feed device 6 pulls the welding wire 11 from the wire stock 5 and promotes this over the wire soul 2 to another wire feed device 9 and from this over the welding torch 10 to the welding process. The sensor is preferred 1 immediately before the other wire feed device 9 arranged as shown schematically in the 2 to 5 is shown.

The sensor is preferred 1 for detecting the fill level or storage volume of the wire buffer store 8th used. In the illustrated welding system 3 becomes a special wire buffer 8th used, in which the wire core 2 with the welding wire 11 at least in a partial area in a wire guide tube, with a substantially larger cross section or inner diameter than a cross section or outer diameter of the wire core 2 is arranged. The storage volume of the wire buffer 8th is defined by the cross-section and the length of the much larger wire guide tube. The inner diameter or cross section of the wire guide tube is at least 1.5 times larger than the outer diameter of the wire core 2 , The wire guide hose can helix-shaped or spiral in the hose package 7 run or is outside the hose package 7 arranged. The wire soul 2 is at one end, preferably in the range of the welding device 3 or an external wire feeder, fixed or fixed, wherein the other end of the wire core 2 in the area of the welding torch 10 or the further wire feed device 9 is freely movable. Thus, it is possible that, for example, in a conveying direction reversal of the wire feed device 9 the wire soul 2 with the welding wire 11 can be moved back into the wire guide tube, or is pulled out of this. So that the level or the storage volume of the wire buffer memory 8th can be determined, the movement of the wire core 2 be detected by a sensor arrangement.

For this purpose, the sensor arrangement, in particular the sensor 1 , a housing 12 on, with the wire soul 2 directly into the housing 12 extends and in the housing 12 an evaluation element 13 is arranged. It is also possible that the wire core 2 through the sensor 1 , in particular its housing 12 , extends therethrough, as in the embodiment of 4 and 5 is apparent. The size of the sensor 1 is designed such that the sensor 1 in the welding torch 10 or in the hose package 7 can be arranged, the sensor 1 preferably in the welding torch 10 , in particular in the burner handle, is arranged.

Furthermore, in this embodiment, on the wire core 2 an indicator 14 arranged rigidly with the wire core 2 connected is. The indicator 14 consists for example of a ferromagnetic material. In the embodiment according to the 2 and 3 forms the indicator 14 the conclusion of the wire soul 2 , whereby the wire soul 2 with the final indicator 14 in the sensor 1 ends. To the longitudinal movement of the wire core 2 To be able to determine contactlessly, there is the evaluation element 13 in the illustrated embodiment according to the 2 and 3 from at least one electric coil 15 ,

Furthermore, the sensor points 1 a spout nozzle 16 for the welding wire 11 on, with an opening whose diameter is only slightly larger than a diameter of the welding wire 11 , This can cause the wire core 2 not through the outlet nozzle 16 extend. The outlet nozzle is preferred 16 via a thread with the housing 12 connected, so that it can be easily replaced, and thus an adjustment of the outlet nozzle 16 to the respective diameter of the welding wire used 11 can be carried out.

The longitudinal movement of the wire core 2 is from the sensor 1 according to the measuring principle of the induction change in the coil 15 detected. This measurement principle is already known from the prior art, so that will not be discussed in more detail on a functional description. In the 6 to 12 different measuring principles are shown schematically, for example, as an evaluation 13 can be used.

The sensor is preferred 1 for determining the fill level or the storage volume of a wire buffer store 8th used. Of course it is possible that the sensor 1 also for other purposes, in which a longitudinal movement of the wire core 2 is to be recorded. The sensor 1 is provided with an evaluation unit or a control device of the welding device 4 connected via lines not shown, which depending on the position of the wire core 2 or the indicator 14 in the case 12 the level of the wire buffer 8th calculated or calculated.

In the 4 and 5 is another embodiment of the sensor 1 shown. In this case, in contrast to the embodiment described above, the wire core 2 now through the case 12 of the sensor 1 guided. The indicator 14 is in turn at the wire soul 2 attached and positioned so that this inside the housing 12 is arranged. This design has the advantage that the sensor 1 not necessarily at the end of the wire core 2 must be arranged, but can be positioned anywhere in the wire feed system. This is an application of the sensor 1 also possible with any known from the prior art welding wire conveyor system and wire buffer memory.

In the following 6 to 12 become the different measuring principles for the use of the evaluation element 13 shown, wherein the sensor 1 is shown schematically and simplified in a cut form. On the exact description of the principles of measurement is omitted, since these are well known from the prior art. The use of the measuring method is both in the embodiments according to the 2 . 3 as well as the 4 . 5 possible, so both in continuous as well as ending wire core 2 ,

In the 6 the distance measurement takes place, ie the longitudinal displacement of the wire core 2 , by inductance change in the coil 15 , Due to the shift of the indicator 14 the inductance of the coil changes 15 so that the position can be determined by a connected evaluation unit or control device.

Instead of the measuring principle of the inductance change, an arrangement with a capacitance change is also possible, as shown in FIG 7 is shown. This causes a movement of the indicator 14 a change in the dielectric and thus a change in the total capacity, which in turn can be deduced on the position.

An amplification of the output signal of the sensor 1 can by suitable arrangement of two coils 15 , according to 8th , to be achieved, with the spacing of the coils 15 the size or length of the indicator 14 equivalent. In the process, the evaluation element becomes 13 formed by a Wheatstone bridge circuit for differential evaluation of the measurement signal. In such a solution, the noise immunity of the sensor 1 significantly improved.

Of course it is also possible that the two coils 15 immediately adjacent can be arranged, like this 9 is apparent. It is also possible that several coils 15 can be arranged.

It is also possible to use the evaluation element 13 according to the transformer principle, as in 10 can be seen, build, wherein a transmitting coil 17 and one or more receiving coils 15 . 18 are arranged. By the respective position of the indicator 14 be in the receiving coil 15 . 18 caused different magnetic couplings, so that in turn an evaluation of the position is possible.

It is also possible to make an optical position determination, as in the 11 and 12 is shown. In these embodiments, the housing has been 12 of the sensor 1 not shown. For the optical non-contact measuring principle are transmitting and receiving diodes 19 and 20 , ie light sources and photosensitive elements arranged. In this case, a reflection or transmitted light principle can be used. The reflection principle is the transmitting and receiving diodes 19 and 20 adjacent, according to 11 , arranged and is the indicator 14 formed by a reflective material. In transmitted light principle are the transmitting and receiving diodes 19 and 20 opposite, according to 12 , arranged and is the wire soul 2 or the indicator 14 arranged between these. With the transmitted light principle, it is also possible that the indicator 14 deleted and the position determination depending on the coverage of the transmitting and receiving diodes 19 and 20 is evaluated.

It is also possible, the evaluation unit directly into the housing 12 integrate so that from the sensor 1 , in particular the evaluation unit, directly the position of the wire core 2 or the indicator 14 can be output, which is then from the welder 3 or the control device of the welding device 3 or another control device can be further processed.

Furthermore, it is also possible that the wire core 2 in front of the sensor 1 ends and only the indicator 14 in the sensor 1 protrudes or that a special end element with the wire core 2 is coupled, on which the indicator 14 is arranged. This would make it possible for the wire core 2 For example, by a coil spring is formed in front of the sensor 1 ends and then the end element of a magnetically non-conductive part with indicator arranged thereon 14 when using the induction measurement method, with the wire core 2 is coupled.

Claims (17)

Sensor arrangement for detecting the movement of a wire core ( 2 ) in a welding plant ( 3 ) through which wire core ( 2 ) a welding wire ( 11 ) between two wire feed devices ( 6 . 9 ), with one, the welding wire ( 11 ) surrounding sensor ( 1 ) with a housing ( 12 ) and an evaluation element ( 13 ), one through the wire core ( 2 ) or with the wire core ( 2 ) associated indicator ( 14 ), which indicator ( 14 ) in the sensor ( 1 ) is displaceable force-free in the longitudinal direction, and wherein the evaluation element ( 13 ) in the housing ( 12 ), characterized in that the wire core ( 2 ) directly into the housing ( 12 ) or by the Gehgäuse ( 12 ) of the sensor ( 1 ). Sensor arrangement according to claim 1, characterized in that the sensor ( 1 ) in front of a wire feed device ( 9 ) and preferably one between the wire feeders ( 6 . 9 ) wire buffer memory ( 8th ) is arranged so that over the longitudinal movement of the wire core ( 2 ) the level or the storage volume of the wire buffer memory ( 8th ) is detectable. Sensor arrangement according to claim 2, characterized in that the sensor ( 1 ) immediately in front of the wire feed device ( 6 . 9 ) or immediately after the wire buffer memory ( 8th ) is arranged. Sensor arrangement according to one of claims 1 to 3, characterized in that the sensor ( 1 ) with an evaluation unit or a control device of the welding system ( 3 ) or the welding device ( 4 ) is connectable. Sensor arrangement according to one of claims 2 to 4, characterized in that the sensor ( 1 ) with a wire feed device ( 6 . 9 ), so that the wire feed corresponding to the level or storage volume of the wire buffer memory ( 8th ) is controllable. Sensor arrangement according to one of claims 1 to 5, characterized in that the sensor ( 1 ) in a welding torch ( 10 ), in particular in a torch handle or in a hose package ( 7 ) is arranged. Sensor arrangement according to one of claims 1 to 6, characterized in that the indicator ( 14 ) fixed to the wire core ( 2 ) connected is. Sensor arrangement according to one of claims 1 to 6, characterized in that the indicator ( 14 ) detachable with the wire core ( 2 ) connected is. Sensor arrangement according to one of claims 1 to 8, characterized in that the indicator ( 14 ) the conclusion of the wire soul ( 2 ). Sensor arrangement according to one of claims 1 to 9, characterized in that the sensor ( 1 ) an outlet nozzle ( 16 ) for the welding wire ( 11 ) having. Sensor arrangement according to claim 10, characterized in that the outlet nozzle ( 16 ) with the housing ( 12 ) of the sensor ( 1 ) is releasably connected. Sensor arrangement according to one of claims 1 to 11, characterized in that the indicator ( 14 ) consists of ferromagnetic material. Sensor arrangement according to one of claims 1 to 12, characterized in that the evaluation element ( 13 ) from at least one electrical coil ( 15 ) consists. Sensor arrangement according to one of claims 1 to 11, characterized in that the evaluation element ( 13 ) by a plurality of light sources, in particular transmitting diodes ( 19 ) and opposite photosensitive elements, in particular receiving diodes ( 20 ), between which the indicator ( 14 ) forming wire core ( 2 ) or with the wire core ( 2 ) indicator ( 14 ) is arranged. Sensor arrangement according to one of claims 1 to 11, characterized in that the indicator ( 14 ) is formed by a light-reflecting material and the evaluation element ( 13 ) by a plurality of light sources, in particular transmitting diodes ( 19 ) with adjacently arranged photosensitive elements, in particular receiving diodes ( 20 ) is formed. Sensor arrangement according to one of claims 4 to 15, characterized in that the evaluation unit or control device in the housing ( 12 ) of the sensor ( 1 ) is arranged. Welding system with a welding device ( 4 ), a hose package ( 7 ) and a welding torch ( 10 ), whereby the hose package ( 7 ) the welding torch ( 10 ) with the welding device ( 4 ), wherein between two wire feed devices ( 6 . 9 ) as a wire buffer memory ( 8th ) apparatus for buffering one within a wire core ( 2 ) guided welding wire and further a sensor ( 1 ) for non-contact measurement of the movement of the wire core ( 2 ), characterized in that the sensor ( 1 ) is formed according to one or more of claims 1 to 16.