Operating process for an irradiation device
Known operating processes for an irradiation device for irradiating a substrate by a UV emitter include the process steps of: (a) operating the UV emitter at a nominal operating radiation power; (b) continuously feeding the substrate at a feed rate into the irradiation field; and (c) irradiating the substrate in the irradiation field defined by the UV emitter. In order to devise, on this basis, a simple and inexpensive operating process for an irradiation device, which makes a short start-up time feasible after an interruption of the production process, the UV emitter is switched off when there is an interruption of the continuous substrate feed. The emitter temperature of the switched-off UV emitter is measured, and provisions are made for counter-measures to counteract a decrease of the emitter temperature by more than 10° C. below the nominal operating temperature.
1. An operating process for an irradiation device for irradiating a substrate by a UV emitter, the process comprising steps of:
(a) operating the UV emitter at a nominal operating radiation power that is a function of a nominal operating temperature;
(b) continuously feeding the substrate, at a feed rate, into an irradiation field defined by the UV emitter; and
(c) irradiating the substrate in the irradiation field,
wherein the UV emitter is switched off if there is an interruption of the continuous substrate feed, wherein an emitter temperature of the switched-off UV emitter is measured, and wherein counter-measures are provided to counteract a decrease of the emitter temperature by more than 10° C. below the nominal operating temperature.
2. The operating process according to claim 1 , wherein one of the counter-measures comprises heating the UV emitter by a heating element.
3. The operating process according to claim 1 , wherein the emitter temperature is influenced by an air flow generated by air cooling, and wherein one of the counter-measure comprises heating of the air flow by a heating element.
4. The operating process according to claim 1 , wherein the emitter temperature is influenced by an air flow generated by air cooling, and wherein one of the counter-measures comprises changing a mass flow of the air flow.
5. The operating process according to claim 2 , wherein, if the continuous substrate feed is interrupted,
(aa) the UV emitter is switched off; and
(bb) the heating element is switched on;
and when the interruption of the continuous substrate feed is no longer present;
(cc) the UV emitter is switched on; and
(dd) the heating element is switched off.
6. The operating process according to claim 3 , wherein the air flow is heated in an air feed channel of the air cooling.
7. The operating process according to claim 3 , wherein the irradiation device comprises a reflector having a side facing the UV emitter and a side facing away from the UV emitter, and wherein the air flow is heated by a heating element arranged on the side of the reflector facing away from the UV emitter.
8. The operating process according to claim 3 , wherein the air flow flows around the UV emitter in a direction perpendicular to a longitudinal extent of the emitter.
9. The operating process according to claim 1 , wherein the feed rate is detected consecutively by a sensor.
10. The operating process according to claim 1 , wherein the temperature of the UV emitter is detected consecutively by a sensor.
11. The operating process according to claim 3 , wherein, if the continuous substrate feed is interrupted,
(aa) the UV emitter is switched off; and
(bb) the heating element is switched on;
and when the interruption of the continuous substrate feed is no longer present;
(cc) the UV emitter is switched on; and
(dd) the heating element is switched off.
12. The operating process according to claim 6 , wherein the irradiation device comprises a reflector having a side facing the UV emitter and a side facing away from the UV emitter, and wherein the air flow is heated by a heating element arranged on the side of the reflector facing away from the UV emitter.
13. The operating process according to claim 4 , wherein the air flow flows around the UV emitter in a direction perpendicular to a longitudinal extent of the emitter.
14. The operating process according to claim 6 , wherein the air flow flows around the UV emitter in a direction perpendicular to a longitudinal extent of the emitter.
15. The operating process according to claim 7 , wherein the air flow flows around the UV emitter in a direction perpendicular to a longitudinal extent of the emitter.