Electric heating – Metal heating – By arc
Patent
1998-10-02
2000-10-10
Mills, Gregory
Electric heating
Metal heating
By arc
21912169, 2191217, 21912171, 21912179, B23K 2608
Patent
active
061304026
DESCRIPTION:
BRIEF SUMMARY
DESCRIPTION
The invention relates to a system of marking or perforating moving objects with a laser, driven by a controlled power source.
STATE OF THE ART
The coding of products, for example, in the pharmaceuticals, foodstuffs and cosmetics industries, requires reliable and permanent identification. The use of a laser beam produces a micro volatilisation of the surface of the material to be marked, thus achieving a permanent and indelible marking whilst the product is on the production line.
The use of lasers for marking moving products on production belts is already known. These systems have an acoustic-optical deflector on which the laser beam is made to reflect and to which, moreover, a given frequency is applied to produce the deflection of the beam. The angle of deflection depends directly on the value of the frequency applied to the deflector, in such a way that a different angle of deflection corresponds to each frequency applied.
European patent No. 0402298 refers to a system of marking moving objects by means of a laser.
In this system, the angle of deflection depends on the value of the frequency of an RF signal that is applied to the deflector, so that a different angle of deflection corresponds to each frequency applied. A number of fixed oscillators of different frequencies are used that are applied to the acoustic-optical deflector through a switching circuit that is controlled by a control circuit that selects the frequency to apply.
The fact that the number of fixed oscillators is a predetermined quantity results in a limited number of frequencies, and therefore, in a limited number of points. If it is wished that the resolution of the marking be increased, the number of oscillators and the control logic have to be increased, which means an increase in their cost. Furthermore, it is known that the efficiency characteristic of the acoustic-optical deflector is not linear in the working frequency band.
OBJECT OF THE INVENTION
An object of the invention is to create a system and a procedure for marking or perforating products by laser that improve and facilitate the marking or perforation.
The invention has many advantages.
The system, according to the invention, illustrated in FIG. 1, affords dynamic control of the resolution for marking or perforation of points in a vertical direction. This system also allows the exposure time to the laser beam for each marking or perforation point to be controlled. Hence the dependence on marking is reduced when faced with changes in speed on production lines.
The system, according to the invention, allows automatic equalisation of the width to be carried out and allows the positioning of the points of marking or perforation to be controlled in the region where the efficiency of the deflector is maximum. In this sense, the system lets the equalisation be carried out depending on the energy time for the point (this is the time that the laser beam coincides within the area corresponding to the point) and allows a mixed equalisation by changing the width and the energy time for the point. The system also allows the energy of the marking or perforation to be controlled and works with relatively short switching times (for example, less than a microsecond).
In practice, this system allows marking with messages in alphanumerical characters, serial numbers, time and date of manufacture, coding sequence, logotypes etc. with various heights and widths at a speed of up to 2,000 metres per minute and over 10,000 characters per second. Furthermore, the system complies with all the specifications for the Class IV laser in accordance with the EN 60825 standard and with the CDRH (Centre for Devices and Radiological Health).
The system, according to the invention, illustrated in FIGS. 2 and 3 allows the adaptation of a low average-power laser with a high capacity for accumulation of energy and generation of high peak powers in short periods of time. Hence, a reduction in the cost is achieved in the system for marking or perforation.
The system, according to the inven
REFERENCES:
patent: 4321564 (1982-03-01), Tregay
patent: 4645900 (1987-02-01), Heyden
patent: 4740269 (1988-04-01), Berger et al.
patent: 4922077 (1990-05-01), Gordon
patent: 4992890 (1991-02-01), Pinard et al.
patent: 5021631 (1991-06-01), Ravellat
patent: 5092350 (1992-03-01), Arthur et al .
patent: 5252257 (1993-10-01), Bryant et al.
patent: 5259401 (1993-11-01), Lange et al.
patent: 5309178 (1994-05-01), Gross
patent: 5653900 (1997-08-01), Clement et al.
patent: 5837962 (1998-11-01), Overbeck
Abella Jordi Llado
Baron Jose Miguel Ibanez
Ravellat Ramon Sans
Mills Gregory
Servicio Industrial De Marcaje Y Codification, S.A.
LandOfFree
System and process for marking or perforating does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with System and process for marking or perforating, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and System and process for marking or perforating will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2258337