DE20115284U1 - Automatic nozzle cleaning device for inert gas welding equipment - Google Patents

Description

Automatic nozzle cleaning device for shielded gas welding machines

The invention relates to a device which enables automatic cleaning of the nozzles and nozzle holders on inert gas welding machines.

Inert gas welding machines are used for a wide variety of welding processes and welding tasks. This is an arc welding process in which the welding filler is supplied via a so-called nozzle holder, which is arranged in a gas nozzle that supplies inert gas during the welding process. Due to the process and the arrangement of the components, the gas nozzle and nozzle holder need to be cleaned regularly. This is due to process-dependent welding spatter and fumes. Failure to comply with the cleaning intervals will result in malfunctions or failure of the welding unit. This is particularly undesirable in automatic, robot-controlled systems.

Currently known nozzle cleaning systems work with different burst, blow and scratch processes, whereby the burner is processed in the assembled state. The cleaning result of these processes is insufficient in most cases, since the process causes the contamination to be pushed deeper into the burner neck or cleaning the nozzle holder is not possible. Other disadvantages of these processes are that subsequent cleaning by operating personnel is required. Furthermore, due to the process, the welding wires are deformed during cleaning and accumulations of welding spatter in the nozzle neck are not removed.

The device specified in claim 1 is based on the objectives of automating the cleaning process carried out by operating personnel on commercially available welding devices, optimizing the cleaning result and minimizing the cycle time of a cleaning process.

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These objectives are achieved with the features listed in claim 1,

■ that a device module (4) is designed in such a way that an automatic release of the threaded connection between the nozzle (7) and the burner base body (24) is achieved,

■ that the nozzle (7) is cleaned simultaneously on both its inside and outside using a special cleaning module (6),

■ that the exposed nozzle assembly (8) is cleaned with a special cleaning module (5) at the same time as the cleaning process of the nozzle (7),

■ that the device module (4) is designed in such a way that an automatic assembly of the nozzle (7) and the burner base body (24) is achieved,

■ that the individual work steps of the device are continuously monitored by the system control (23), or in the case of robot-controlled welding machines, by the robot control,

■ that the device enables the automatic cleaning of both single-wire welding machines (25) which feed the welding filler metal through one wire and double-wire welding machines (26) which feed it through two parallel wires,

solved.

The device enables efficient cleaning of the entire burner, which eliminates the disadvantages described above. The parallel cleaning process of the gas nozzle and nozzle holder makes it possible to achieve a cleaning cycle time that is competitive with conventional methods. The result of the new cleaning process, however, is significantly better, so that burner components only need to be replaced when the wear limit is reached. This concept enables considerable savings potential, particularly in automated systems, while simultaneously increasing the quality of the end products.

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The invention increases the availability of the entire system in which the nozzle cleaning device is used. Disruptions and downtimes are reduced, and maintenance and servicing costs are lowered.

An embodiment of the device is explained with reference to Figures 1 to 6. It

show:

Fig. 1 the overall system of a nozzle cleaning device and its modules,

Fig. 2 a detached nozzle and an exposed nozzle holder of a single wire torch,

Fig. 3 a detached nozzle and an exposed nozzle assembly of a double wire burner,

Fig. 4 the “nozzle turning head” module, Fig. 5 the “nozzle block cleaning” module, Fig. 6 the “nozzle interior cleaning” module.

Figure 1 shows the automatic nozzle cleaning device with the base frame (1), the drive unit (2), the gear unit (3) and the modules nozzle turning head (4), nozzle block cleaning (5) and nozzle interior cleaning (6).

The components of the gas shielded welding equipment to be cleaned are the nozzle (7) and the nozzle holder (8) as shown in Figures 2 and 3; these are connected to one another by a fastening thread. The differences between single-wire and double-wire torches result in different nozzle dimensions.

The nozzle turning head module according to Figure 4 consists of the main components gear (9), insert (10), barrels (11), blade (12) and sensor (13). This enables the parts to be separated and screwed together. In order to enable different mounts, a changing device (14) is provided, which is only shown in outline here.

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The nozzle block cleaning module according to Figure 5 carries out the cleaning process of the exposed nozzle block (8) by means of an integrated drive unit (15) and at least two counter-rotating brush bodies (16). The drive unit (15) can be fed by an independent power source or by gear ratios from the drive unit (2) of the entire device.

Figure 5 shows the swiveling nozzle interior cleaning module with the drive (17), the swivel link (18) and the cleaning assembly. This consists of the hold-down device (19) for the nozzle and the actual cleaning brush (20). This module can optionally be expanded with a blow-out nozzle (21) that blows off the loosened dirt particles and an oil nozzle (22) that applies a release agent to the cleaned nozzle (7). These options are only shown here in outline.

In summary, the operation of the nozzle cleaning device according to the invention is as follows:

If, for example, cleaning of the torch (24) becomes necessary after a predetermined time interval or after contamination detected by sensors, the welding robot moves linearly from above into the nozzle turning head module (4). After the torch (24) has reached its lowest position, the sensor (13) of the nozzle cleaning device detects that the nozzle (7) is correctly positioned within the device. After the release signal from this sensor (13), the robot control (23) automatically starts the next automatic cleaning cycle.

The release signal of the sensor (13) monitors all further work steps of the device and must be present permanently. If this signal drops at any time during the process, this means an error in the respective step. To avoid damage to the

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To avoid damage to the burner components, the robot and the device, the process stops

immediately after signal loss.

The motor power of the drive unit (2) is transferred through the gear unit (3) to the gear (9) of the twisting head (4), causing it to rotate. The direction of rotation of the head (4) is determined in such a way that the nozzle holder thread is loosened. The rotation of the gear (9) is transmitted by means of an insert (10) to integrated barrels (11), which frictionally transfer the torque to the nozzle (7) without causing damage.

The number of barrels (11) is not necessarily dictated by the function. The entire insert (10) represents an independent assembly and can be changed at short notice to adapt to the specific features of the system, like all other nozzle and burner-specific components.

After the burner components are separated, controlled by the process time, the robot control (23) controls the now exposed nozzle assembly (8) from the twist-off head (4), the further working cycle of the device, cleaning of the nozzle (7) and cleaning of the

nozzle holder (8), runs simultaneously.

The nozzle is cleaned by maintaining the rotary motion, whereby the nozzle interior cleaning module (6) is swiveled in and simultaneously lowered into the open nozzle (7). These movements are driven by the module's own drive (17), controlled by the swivel link (18). The hold-down device (19) presses the nozzle (7) against the blades (12), which scrapes off the dirt on the outside of the nozzle (7). At the same time, the brush (20) cleans the inside of the nozzle (7).

The loosened dirt particles can optionally be removed from the nozzle (7) and the turning head (4) by means of a blow-out nozzle (21) and the cleaned surfaces can be sealed with a release agent that is applied by means of an oil nozzle (22).

The nozzle assembly (8) is inserted into the nozzle assembly cleaning module (5) from above. The rotation of the counter-rotating brushes (16) is directed in such a way that the loosened dirt residues are conveyed downwards to the floor of the system. The brush bodies (16) are driven

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by a drive unit (15), which can be provided by its own motor or by suitable gear ratios from the drive unit (2) of the overall device.

The speed of the brushes (16) is approximately 4.5 times higher than that of the turning head (4).

The cleaning time of the two components is determined by the robot control (23), which gives the signal that the cleaned parts are to be reassembled. The nozzle holder

(8) moves back to the original position in the turning head (4), during this movement the robot controller (23) steers the turning head in the opposite direction of rotation.

The clean nozzle (7) and the clean nozzle holder (8) are automatically screwed back together to form a unit; the mechanics of the twist-off head (4) are designed in such a way that the tightening torque is limited by a form of slip clutch.

After the assembly time has elapsed, the cleaned torch (24) returns to its welding task under the control of the robot control (23), the sensor signal (13) drops and any movement of the nozzle cleaning device stops.

The device is immediately ready for another cleaning cycle.

The described embodiment of the device can be modified in many ways without departing from the basic idea.

Claims (6)

1. Automatic nozzle cleaning device for inert gas welding devices, which dismantles the burner assembly for the cleaning process, cleans the dismantled burner components separately from one another, simultaneously in individual device stations and reassembles the burner assembly, characterized in that a device module ( 4 ) is designed in such a way that an automatic loosening of the threaded connection between the nozzle ( 7 ) and the burner base body ( 24 ) is achieved. 2. Device according to protection claim 1, characterized in that the nozzle ( 7 ) is cleaned simultaneously on both its inside and its outside with a special cleaning module ( 6 ). 3. Device according to protection claim 1, characterized in that the exposed nozzle assembly ( 8 ) is cleaned with a special cleaning module ( 5 ), simultaneously with the cleaning process of the nozzle ( 7 ). 4. Device according to protection claim 1, characterized in that the device module ( 4 ) is designed such that an automatic assembly of the nozzle ( 7 ) and the burner base body ( 24 ) is achieved. 5. Device according to protection claim 1, characterized in that the individual working steps of the device are continuously monitored by the system control ( 23 ), in the case of robot-controlled welding devices, the robot control. 6. Device according to protection claim 1, characterized in that the device enables the automatic cleaning of both single-wire welding devices ( 25 ) which feed the welding filler material through one wire, and double-wire welding devices ( 26 ) which feed it through two parallel wires.