ELMA VISION CR VR for robot-guided production in the automotive & industry - ELMA-Tech Gesellschaft für innovative Schweiß- und Beschichtungstechnologie mbH

Robot-guided spot welding guns ELMA VISION CR VR

The industrial robot-guided welding guns CR & VR for fully automatic resistance spot welding are welding guns of the second generation with optimized arm mechanism and higher power and bear the suffix "R" (version for robot-guidedl production).

These guns have been designed for high industrial and automotive requirements of serial production. They are winners in the areas of performance, robustness in continuous use and weight. Executed as lightweight guns, the guns are two-thirds lighter than conventional spot welding guns. This means 70% weight savings for the operator and allows precise and energy-saving guidance of the welding gun.

The ELMA VISION robot welding guns only work in combination with the ELMA-Tech control technology Virtual Machine (VM). Together with the ELMA VMC VISION ROB control cabinet, they form a powerful welding system for automotive and industrial applications.

Significant benefits

Cost savings

Weight reduction allows smaller robots (up to 4 x less energy costs per cell)
Automatic welding process enables a complete reduction in the cost for parameter adjustments for different metal sheet joinings
Almost spatter-free spot welding minimizes rework
Upon detection of splatter or incidental inclusions automatic recalculation and correct completion of the welding process
Automatic gun offset means less programming work
Variable forward stroke position provides a faster throughput

Applications

Features

10 kHz transformer with rectifier (7.5 kg)
High output currents up to 15 kA
Integrated measurement system (automatic detection of sheet thickness)
Fast reacting servo proportional valve directly integrated into the gun
Automatic regulation of electrode force
Integrated quality system ELMA-QS with clear quality statement about the welding spo
Documentation of welding parameters by means of Spot QS Viewer software (optional)
Gun body can be completely dismantled from one side

Technological basis

Welding guns in lightweight construction (sandwich method of construction)
Regulated servo pneumatic actuators for electrode movement and balance
Precision measurement technology for main and compensating cylinder
10 kHz transformer, 7,5 kg, 15 kA
Process and servo-control via Virtual Machine
Virtual measuring points for the welding voltage on the electrode caps
Virtual generators with lossless coupling to the electrode caps
Automatic adjustment of the static and dynamic generator characteristic
Continuous monitoring of the power conversion in the component

Fully automatic system

Fully automatic means here that the robot positions the gun at the place of the point to be welded. In the following, the responsibility is discharged to the gun and welding control without any parameter guidance. The control performs the following steps:

Closing the gun arms with automatic balancing (float mode)
Force generation and detecting the overall sheet thickness
Calculation of the spot energy to be inserted
Start of the welding process with phase-dependent generator characteristic
Determining the quality of steel (normal / high-strength)
Terminating the process with the determined point energy
Qualification of the process
Opening of the gun (7th axis function), disabling the balance of the gun
Output of the FK switch contact to the roboter

Robot interface

Easy robot connection by handshake between the robot and VM-control!

So far the main and compensating cylinder have been controlled by the robot and the power by the welding control. For this purpose, these systems needed to be linked with their own control components with one another via the robot.

Such cross-linking does not apply to the ELMA-Tech control Virtual Machine (VM) with full automation for the welding process and the gun offset.

The ELMATECH control with VM takes holistically the function control of all gun components, this includes the measuring techniques for detecting the total sheet thickness, the electrical process control, stroke and force control of the master cylinder and the balance control of the compensating cylinder.

For this main and compensating cylinder were equipped with measurement systems, so that both cylinders together with the control form pneumatic servo systems. This means precise positioning before and after welding in the shortest possible time for the master cylinder. There is no longer a forward stroke by special mechanical design of the master cylinder. The cylinder thus has become very easy and safe to operate.

General technical data

Connection data