Disconnection box for a robot system

A switch-off box for a robot system has a two-part housing and a coupling device resiliently mounted in the housing and connected to a torch body and a hose pack or to a torch handle connected with the hose pack, and having a supporting surface for punctual contact on the housing. There are contacting or switching elements connected to the coupling device. Two oppositely located openings are provided in the housing for connection of the coupling device to the torch body and for connection of the coupling device to the hose pack or the torch handle. The supporting surface is connected with the contacting or switching elements so that a respective contacting or switching element will be activated or deactivated by lifting of the supporting surface from the housing, and a signal will be transmitted from the contacting or switching element to an interfaced control device, or the robot system.

CROSS REFERENCE TO RELATED APPLICATIONS

Applicants claim priority under 35 U.S.C. §119 of Austrian Application No. 1524/2002 filed Oct. 8, 2002. Applicants also claim priority under 35 U.S.C. §365 of PCT/AT2003/000300 filed Oct. 6, 2003. The international application under PCT article 21(2) was not published in English.

BACKGROUND OF THE INVENTION

1. Field of the Invention.

The invention relates to a switch-off box for a robot system, including a coupling means resiliently mounted in a housing and designed to be connected to a hose pack and a welding torch formed by a torch body and, optionally, a torch handle.

2. The Prior Art.

Collision protection detection means or switch-off boxes are known from the prior art, yet these are directly installed in robots, i.e., in a robot arm. Components are attached to those switch-off boxes integrated in the robots. This involves the disadvantage of such integrated switch-off boxes having to take up the entire weight of the attached components and hence to be very rigidly designed, thus adversely affecting the switch-off behavior.

From U.S. Pat. No. 4,540,869 A, a welding torch for use in a welding robot comprising a collision protection means is known, which includes a resiliently mounted coupling element designed to be connected to a hose pack and a welding torch. This entails the drawback of a relatively complex construction, which also serves to allow radial movements of the welding torch.

JP 7-178546 A likewise discloses a welding torch including a collision protection means, yet the connection of the hose pack is not illustrated. If the hose pack were to be fastened to the coupling means, the switch-off box would have to take up the very high weight of the components attached to the same, thus adversely affecting the switch-off behavior.

GB 1 224 180 A shows a device for controlling the movement of a tool, for instance a welding torch, in which a finder can be mounted to detect the path of movement of the tool. On a robot arm connected with the finder are arranged elements to detect a collision of the finder with the tool and actuate the motors of the robot control accordingly. Again, the switch-off behavior is adversely affected because of the collision detection means being installed in the robot arm.

SUMMARY OF THE INVENTION

The object of the present invention, therefore, consists in providing an independent switch-off box capable of being flexibly used at any desired site or position of the robot system. In addition, the switch-off box is to be configured in a manner as simple as possible and characterized by as quick and simple a response as possible.

The objects according to the invention are achieved in that the housing is comprised of two parts and the coupling means is designed for punctual contact on the housing. This offers the advantage of the switch-off box being directly arrangeable in the welding torch, i.e., between the individual components of the welding torch. The switch-off box may, thus, be positioned as close to the jeopardized region as possible so as to readily detect already slight collisions. A further advantage resides in that the hose pack and the torch handle, respectively, can be connected with the switch-off box such that the latter will take up the weight of the components and the resiliently mounted coupling means of the switch-off box need only be dimensioned to fit the weight of the torch body. The punctual contact of the coupling means on the housing ensures the rapid response behavior of the switch-off box, since, at the occurrence of a collision, such collision will be immediately detected by the opening of the punctual contact and the respective control of the robot system will be enabled by the appropriate arrangement of contacting elements or switching elements.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

FIG. 1depicts a welding device1or welding apparatus for various processes and methods such as, e.g., MIG/MAG welding or WIG/TIG welding or electrode welding methods, double wire/tandem welding processes, plasma or soldering methods etc. It is, of course, possible to use the solution according to the invention with a power source or welding current source.

The welding device1comprises an energy source2including a power element3, a control device4and a switch member5associated with the power element3and the control device4, respectively. The switch member5, and the control device4, are connected with a control valve6arranged in a feed line7for a gas8and, in particular, a protective gas such as, for instance, CO2, helium, argon and the like, between a gas reservoir9and a welding torch10, or a burner, respectively.

In addition, a wire advance system11common to MIG/MAG welding can be activated via the control device4, with a filler metal or a welding wire13being fed via a feed line12from a supply drum14into the region of the torch10. It is, of course, also possible to integrate the wire advance system11in the welding device1and, in particular, in the basic housing, as is known from the prior art, rather than design it as an accessory unit as illustrated inFIG. 1.

It is also possible for the wire advance system11to supply the welding wire13, or filler metal, to the process site externally of the welding torch10, to which end a non-consumable electrode is preferably arranged in the welding torch10, as is common with WIG/TIG welding.

The power required to build up an electric arc15and, in particular, an operative electric arc, between the welding wire13and a workpiece16is supplied from the power element3of the energy source2to the welding torch10through a welding line17, wherein the workpiece16to be welded, which is comprised of several parts, is likewise connected with the welding device1and, in particular, the power source2via a further welding line18, thus enabling a power circuit for a process to build up over the electric arc15, or the plasma jet formed.

To provide cooling of the welding torch10, the welding torch10is connectable to a fluid reservoir and, in particular, water reservoir21via a cooling circuit19with a flow control20interposed, whereby the cooling circuit19, particularly a fluid pump used for the fluid contained in the fluid reservoir21, is started as the welding torch10is being put into operation, thus effecting cooling of the welding torch10.

The welding device1further comprises an input and/or output device22, via which the different operating parameters, modes of operation or welding programs of the welding device1can be adjusted and/or called. In doing so, the welding parameters, modes of operation or welding programs adjusted by the input and/or output device22are transmitted to the control device4, which, in turn, will subsequently activate the respective components of the welding apparatus or welding device1.

Furthermore, the welding torch10in the exemplary embodiment illustrated is connected with the welding device1or welding apparatus via a hose pack23. The individual lines leading from the welding device1to the welding torch10are arranged within the hose pack23. The hose pack23is connected with the welding torch10via a coupling device24or central connection, whereas the individual lines within the hose pack23are connected with the individual contacts of the welding apparatus1via connection sockets or plug-in connections. In order to ensure the appropriate strain relief of the hose pack23, the hose pack23is connected with a housing26and, in particular, the basic housing of the welding device1via a strain relief means25. The coupling device24may naturally also be used for the connection on the welding device1.

Basically, it should be noted that not all of the afore-mentioned components need be used or employed for the various welding methods or welding devices1such as, for instance, WIG devices or MIG/MAG devices or plasma devices.

InFIGS. 2 and 3, an application example of a switch-off box27for a robot system and, in particular, a welding apparatus is illustrated. In this case, the switch-off box27is directly arranged on the welding torch10, namely between a torch body28and a hose pack23inFIG. 2, and between the torch body28and a torch handle29inFIG. 3, which torch handle, for instance, includes an integrated wire feed to which the hose pack23is connected. The welding torch10with the integrated switch-off box27is fastened to a robot system (not illustrated) by the aid of a fastening means30.

The use of the switch-off box27directly on the welding torch10offers the advantage of the switch-off box27having to take up less weight, thus exhibiting an improved switch-off behavior in the event of a collision. Moreover, the independent switch-off box27ensures optimum adaptations to be made in the arrangement of the switch-off box27, since the latter may be used at the most diverse points in the robot system. It is also feasible to use the switch-off box27in such a manner that no welding components are connected, but that it is, for instance, used between the robot arm and the fastening means30for the welding torch10.

FIGS. 4 to 7schematically illustrate the switch-off box27in detail, wherein a coupling means34is resiliently mounted in a housing33comprised of two parts31,32. The coupling means34is designed for the connection of the welding torch10, particularly its components, and the hose pack23, with a commercially available central connection or coupling device from welding technology being realized on the coupling element34to connect the hose pack23with the welding torch10. The function of the switch-off box27resides in performing a collision detection, whereby the switch-off box27is designed as a compact structural unit and hence an independent component capable of being appropriately positioned as a function of its field of use.

The switch-off box27is configured in a manner that the coupling means34is resiliently mounted in the housing33comprised of two parts31,32wherein the coupling means34projects out of the housing33through an opening35, whereas the other end of the coupling means34may terminate in the interior of the housing33. The torch body28may be fastened to the projecting end of the coupling means34. A cavity36is formed in the interior of the housing33. The coupling means34is preferably insulated relative to the housing33, thus allowing electric energy and, in particular, welding current, to be transmitted via the coupling means34. To this end, an insulation ring37is arranged in the exemplary embodiment illustrated. Channels38may be arranged within the coupling means34, whereby the supplied media such as, for instance, cooling liquid, protective gas, etc. may be transferred from one side of the coupling means34to its other side, thus safeguarding the function of the welding torch10. Furthermore, the coupling means34comprises a supporting surface39for the punctual contact on the housing33, which supporting surface in the exemplary embodiment shown is formed by an external ring40having an L-shaped cross section and fastened to the insulation ring37. Said external ring40having an L-shaped cross section may be designed to extend circumferentially or to comprise only some sections. Thus, it is ensured, on the one hand, that the coupling means34will be secured against slipping out of the housing33and, on the other hand, that a punctual contact will be provided in the housing33. It is, in fact, essential that the coupling means34contacts the housing33only point-wisely so as to enable the point-wise lifting from the housing33in the event of a collision. The external ring40may, of course, also be formed by the coupling means34.

In order to ensure a punctual abutment or contact on the housing33, projections41are arranged on the external ring40so as to ensure punctual bearing on the housing33. Instead of the projections41, it is also feasible to use other spacer elements such as, for instance, spheres, in order to provide a punctual contact between the supporting surface39and the housing33. In a preferred manner, three or five projections41are arranged there. The fixation of the coupling means34is realized by the aid of a screw connection42through the external ring40and the supporting surface39, respectively, with a spring element44arranged between a screw head43and the external ring40and the supporting surface39, respectively. Thus, the entire coupling means34is resiliently mounted so as to cause the suitable displacement of the coupling means34at a collision of the connected parts and, in particular, the torch body28with a solid object. In order for this to be detected, contacting elements or switching elements48are connected with the projections41and the supporting surface39, respectively, in a manner that the contacting element will be activated or deactivated by the lifting of a single projection41from the housing33and a signal will, thus, be transmitted from the contacting element or switching element to an interfaced control device4, or the robot system.

Furthermore, another opening45is provided in the housing33on the opposite side of the emergence of the coupling means34such that the lines supplied through the hose pack23may be conducted into the housing33to the coupling means34. In a preferred manner, a further projection, or a thread46, is arranged to connect an external hose of the hose pack23to the housing33. This is to ensure that the weight of the hose pack23will not directly act on the coupling means34, but will be transmitted onto the housing33of the switch-off box27. The spring elements44for the mounting of the coupling means34may, thus, be designed to be weaker so as to considerably enhance the response behavior of the switch-off box27.

In principle, is should also be noted that the switch-off box27serves to detect a collision with an object, of the torch body28fastened to the switch-off box27. This is effected by a displacement or movement of the coupling means34in the interior of the housing33, thus causing a projection41to be lifted and a signal to be delivered. In doing so, it is essential that the coupling means34is mounted in the housing33in a manner that a defined displacement and, in particular, lifting of the punctual bearings within the housing33, of the switch-off box27will be ensured at the occurrence of a collision. It is, in fact, thus feasible to effect the suitable detection of a movement of the coupling means34by simply arranging contacting elements or switching elements, which constitutes a substantial structural simplification.