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DUNKES - assembly presses

Insertion pressing and joining operations, additionally monitored with advanced camera technology.

 

Hydraulic single column, double column, or custom presses for assembly processes are an additional pillar of the extensive manufacturing product line supplied by S. Dunkes. The press forces for C-frame presses range from 25 kN to 10,000 kN. Presses are configured depending on the customers task. The presses themselves are either equipped with a CNC or NC control. The ram axis itself is controlled with a proportional valve hydraulic system. This approach permits accurately reproducible end positions with tolerances of +/- 0,02 mm.


Fabrication operations such as joining, calibrating, straightening, press riveting, assembling, compressing, deburring, or crimping are some of the primary tasks. The press is fitted with handling systems, indexing roundtables, as well as robots for automatic loading and unloading in accordance with the required unit volume. A force-distance measurement must be performed, specifically for insertion pressing of components. This is accomplished either directly or indirectly.


A load cell or strain gauge system is used to eliminate the friction forces on the ram guide and the piston seals. The special analysis unit is used to define appropriate measurement envelopes that check the force versus distance, relative to the insertion pressing travel.
When the measured forces are within the specified tolerance, the pressing operation is accepted. When this is not the case, the ram will stay in the closed position, and the operator is required to cancel error 1, and must insert a new part.
This type of quality control has been performed with the appropriate methods for some time.

 

Quality monitoring mechanism for a manual assembly process and its various tasks:

  • identification of parts to be assembled before assembly (was the correct part assembled)
  • quality control of the assembly process (was the part assembled correctly)
  • control of a technological process (determining location and orientation) 

The benefits of this additional monitoring are clear: 

  • objective inspection (can be integrated into the QA system: DIN EN ISO 9001 compliant)
  • automatic analysis coupled with tool releases
  • template database for specification values of parts to be recognised (data transfer from RS-232)
  • statistics for series support and to monitor process reliability
  • automatic visual test of the inspection facility (e.g. light test and calibration)
  • menu controlled user interface
  • remote maintenance option

 

the inspection plan is the basis for the quality monitoring system. An inspection plan in FERinspPC 1.5 is essentially a collection of data structures that determine the item and the methods to be used for testing. The inspection plan is distorted the file with the name of the component drawing number. Respectively one or several system cameras are assigned to the individual inspections. The inspection plan is taught in a menu-driven manner, while using a variety of tools. For instance, the marker and the blob tools are available to determine clearance dimensions. The pattern tool is available to differentiate image sections (e.g. orientation recognition).


As is typically the case in Windows software, the programme window consists of a programme row, a menu bar, a symbol bar, and a status row in the lower section of the window. The programme name and the currently opened inspection plans are indicated in the programme row. The programme functions can be retrieved via the menu using the mouse or a keyboard combination. The status row displays current information about the programme status and error messages. Certain frequently used functions can also be selected with buttons in the symbol bar.


In summary, a total solution was supplied in collaboration with a customer from the automobile industry, so that this process could be monitored on class 1 safety components. In comparison to mechanical monitoring solutions or fully automated systems, this intermediate level provides an ideal complement with respect to the price/performance comparison


Moreover, these systems are also used for quality monitoring purposes on fully automated plants. However, a fully automated assembly process with bulky or heavy parts is too expensive, or not possible due to specific component characteristics,. S. DUNKES will gladly develop an individual proposal for this in response to a specific enquiry.

Customer training on a DUNKES assembly press.