LOCCIONI I R&D I REFRIGERATORS
A complete quality control system for refrigerators
The traditional quality control test for refrigerators verifies the internal
temperature, the power absorption and lasts from 30 to 90 minutes
with high disadvantages in terms of energy, time and space
consumption.
Nowadays most of the leading refrigerators manufactures are
implementing short time testing controls in production line and are
demanding for a complete characterization of the 100% of the
products at the end of the production line. The use of a non contact
technology based on infrared analysis is suitable for this purpose.
Moreover, in order to give a more complete analysis of the behaviour
of the refrigerators during the test, the power consumption of the
machine is acquired as well as the noise and vibration emitted by the
compressor.
In particular, more technologies are available in order to satisfy these
requirements, such as:
- Infrared analysis for non contact thermography test
-Power consumption analysis for a complete characterization of the
refrigerators and its components
- Vibration test for diagnosis of electromechanical components
- Machine vision test for the display verification
These technologies with a completely automated carousel for the
handling of the refrigerators and a data tracking system that follows
the product since the beginning of the assembly line, guarantee a
high quality control of the 100% of the production.
Thermovision test
The automatic system for the refrigerators testing adopts:
- a non-contact thermal camera
- an advanced signal processing technique for defects analysis,
classification and ambient temperature compensation
The system considers the outside rear part of the refrigerators and
verifies the temperature in order to establish the quality of the object
under test at the end of the assembly line on the 100% of the
production. The system particularly focuses on the inlet and outlet
tubes temperature of the condenser and on the compressor to
automatically detect colder and hotter points and therefore to
classify the appliance as good or faulty.
The thermovision test is based on a comparison between
temperature values read in some specific areas with specified
parameters (object emittance, distance). A good refrigerator is taken
as reference and the obtained parameters and values are compared
to a new refrigerator at a specific time after the machine has been
powered on.
The refrigerators have to be positioned in a carousel in which the
refrigerator can move with precision in terms of space and time. After
a fixed period of time the thermovision test is activated and the
thermal image is acquired and analysed. In case of defects
detection, the refrigerator will be sent to the repair station.
LOCCIONI I R&D I REFRIGERATORS
Power consumption test
During the whole duration of the testing the power consumption of the refrigerator is monitored in each position of the carousel
where a wireless data acquisition has been positioned.In this way the different devices in the refrigerators such as electrovalves,
lamps, ... can be tested if an autotest procedure is implemented in the refrigerator.
Laser Vibrometer Test
In order to verify the vibration level of the compressor a non contact vibration measurement will be performed using a Laser Doppler
Vibrometer (LDV) positioned in front of the compressor. The laser has to be pointed in correspondence of the label, because the
laser vibrometer can not measure on black surface. It is very important to verify that all the compressors have the label positioned at
the same height on the compressor. The signal from the LDV is acquired, analysed and then based on some features that have been
selected, the compressor is classified as good or faulty.
Machine Vision Test
Machine Vision supports test and quality control systems and present the advantage of absolute objectivity in comparison with
human operators inspection. The systems are developed to verify presence/absence and the correct assembling of components
and subassemblies and it can also be used to perform high precision measurement on devices under control avoiding any contact
with them.
Advantages
- Reliability and accuracy of the test
- Improvement of production efficiency and product quality
- Reduction of the testing time and consequent Energy saving
- Reduction of the space dedicated to the testing area
- System customization on customer's needs
- System automation
- User-friendly interface (Human-Machine Interface)
AEA, Via Fiume 16
60030 Angeli di Rosora, Ancona, Italy
Phone +39 0731 8161 Fax +39 0731 814700
[email protected] www.loccioni.com