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(11) | EP 2 089 228 B1 |
| (12) | EUROPEAN PATENT SPECIFICATION |
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| (54) |
COOLING SYSTEM FOR INK CURING APPARATUS KÜHLSYSTEM FÜR DRUCKFARBENHÄRTUNGSVORRICHTUNG SYSTÈME DE REFROIDISSEMENT POUR APPAREIL DE DURCISSEMENT D'ENCRE |
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| Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention). |
[0002] Ink curing apparatus comprising a housing containing a lamp partially surrounded by reflectors to direct UV light onto a. substrate to cure ink are well known, see for example WO-A1-96/34 700, DE-A1-10 109 061, and EP-A1-0 146 998.
[0003] Such apparatus require highly efficient cooling systems due to the intense heat required to be emitted from the lamp.
[0004] Commonly, such apparatus utilise complicated water cooling systems that require a network of pipes, the apparatus requiring many inlets and outlets to provide flow of water across the apparatus components.
[0005] Other known cooling methods include passing the redundant hot air from the lamp through a heat exchanger built within a separate large cooling unit.
[0006] The present invention seeks to provide an improved cooling system that is fully self-contained within a single housing and in which hot air is cooled as it flows over the apparatus components before being recycled through the system.
[0007] Accordingly, in one aspect there is provided an ink curing apparatus having a fully self-contained cooling system, the apparatus comprising a single housing, in one end of which is provided a lamp and in the other end of which is provided a fan, the apparatus having defined therein a path to direct air emitted from the lamp, in use, over cooled surfaces within the housing towards the fan, and having further defined therein a further path to direct air over cooled surfaces within the housing from the fan towards the lamp.
[0008] Preferably the cooled surfaces within the housing are cooled by water channelled through at least one pipe within the housing.
[0009] Preferably still, the cooled surfaces include surfaces of at least one reflector which at least partially surrounds the lamp.
[0011] One embodiment of the present invention will now be described by way of example with reference to the accompanying drawing which is a schematic cross-sectional view of an ink curing apparatus incorporating a cooling system constructed in accordance with the present invention.
[0012] The majority of the curing apparatus shown in the figure is conventional with standard components. For simplicity, only the components relevant to the present invention will be described in detail.
[0013] The apparatus comprises a single housing 10 a lower end 12 of which contains a lamp 14 partially surrounded by reflectors 16, 18. In use, a substrate 20 which carries ink for curing/drying is transported through the apparatus directly beneath the lamp 14. When the reflectors 16, 18 are in an open position, UV light is directed on to the substrate for a period of time sufficient to dry/cure the ink on the substrate 20.
[0015] The ancillary parts of the apparatus within the housing 10, including the surfaces of each reflector 16, 18 are water-cooled using a "parallel system". In such a system the water pipes 26 include inner and outer channels 26a, 26b. In use, cold water is directed into the apparatus through the inner channels 26a of the pipes 26 before being reversed such that the water, once hot, is directed out of the apparatus via the outer channels 26b of the pipes 26.
[0016] Using such a parallel system allows a back plate of the apparatus to require only one inlet and one outlet for coolant. The inlet and outlet are attached to a baffle plate (not shown) within the apparatus, whereupon the inlet and outlet are divided into a plurality of pipes 26 which extend throughout the apparatus to cool all the ancillary parts.
[0017] During use, the lamp 14 emits heat at around 750°C. The UV heat is directed onto the substrate 20. A portion of the IR heat is absorbed into the surfaces of the reflectors 16, 18. The remaining IR is drawn upwardly through the housing via the fan 24. The path of the IR is shown by arrows in the Figure. On its way to the fan 24 the air is drawn over top surfaces 28, 30 of the reflectors 16, 18 which are kept cool via the water pipes 26.
[0018] The apparatus is designed in such a way as to direct the hot air from the lamp 14 over as many cooled surfaces of the ancillary components as possible. Tests have shown that, by the time air emitted from the lamp 14, and travelling over the cooled surfaces as shown, reaches the fan 24 it has reduced in temperature to around 70°C. The air is now drawn over cooled surfaces 32 of the upper end 22 of the housing 10 before being directed over cooled surfaces of the sides of the housing 10 back into the lower end 12. As the air travels down the sides of the housing 10, the temperature decreases progressively. Finally, the air, now at around 32°C, is fed back towards the lamp 14.
[0019] In the present cooling system the fan 24 only requirement of the fan 14 is to provide cooling for the lamp 14. The fan 14 does not need to provide cooling to the other ancillary components of the apparatus as they are cooled separately by the water pipes 26. Consequently, the size of the fan can be greatly reduced.
1. An ink curing apparatus having a fully self-contained cooling system, the apparatus
comprising a single housing (10), in one end (12) of which is provided a lamp (14),
characterised by:
the single housing (10) including in the other end (22) a fan (24); and
the apparatus having defined therein a path to direct air emitted from the lamp (14), in use, over cooled surfaces (28, 30) within the housing (10) towards the fan (24), and having further defined therein a further path to direct air over cooled surfaces (32) within the housing (10) from the fan (24) towards the lamp (14).
2. Apparatus according to claim 1, wherein the cooled surfaces (28, 30, 32) within the
housing are cooled by water channelled through at least one pipe (26) within the housing.
3. Apparatus according to claim 1 or claim 2, wherein the cooled surfaces (28, 30) include
surfaces of at least one reflector (16, 18) which at least partially surrounds the
lamp (14).
4. Apparatus according to claim 2 or claim 3, wherein the or each pipe (26) includes
inner (26a) and outer (26b) discrete channels.
5. Apparatus according to claim 4, wherein cold water is directed into the apparatus
through the inner channel (26a) of the or each pipe (26) and hot water is directed
out of the apparatus through the outer channel (26b) of the or each pipe (26).
1. Eine druckfarbenhärtende Vorrichtung, die ein vollkommen in sich geschlossenes Kühlsystem
aufweist, die Vorrichtung umfasst ein Einzelgehäuse (10), in deren einem Ende (12)
eine Lampe (14) bereitgestellt ist, dadurch gekennzeichnet, dass:
das Einzelgehäuse (10) an dem anderen Ende (22) ein Lüfterrad (24) beinhaltet; und
die Vorrichtung in ihrem Inneren einen Pfad festlegt, um während des Betriebs von der Lampe (14) emittierte Luft über gekühlte Oberflächen (28, 30) innerhalb des Gehäuses (10) gegen das Lüfterrad (24) zu lenken, und weiterhin in ihrem Inneren einen Pfad festlegt, um Luft über gekühlte Oberflächen (32) innerhalb des Gehäuses (10) von dem Lüfterrad (24) gegen die Lampe (14) zu lenken.
2. Vorrichtung nach Anspruch 1, wobei die gekühlten Oberflächen (28, 30, 32) innerhalb
des Gehäuses durch Wasser gekühlt sind, dass durch mindestens ein Rohr (26) innerhalb
des Gehäuses geführt wird.
3. Vorrichtung nach Anspruch 1 oder 2, wobei die gekühlten Oberflächen (28, 30) Oberflächen
von mindestens einem Reflektor (16, 18) einschließen, der mindestens partiell die
Lampe (14) umgibt.
4. Vorrichtung nach Anspruch 2 oder 3, wobei das oder jedes Rohr (26) separate innere
(26a) und äußere (26b) Röhrchen einschließt.
5. Vorrichtung nach Anspruch 4, wobei kaltes Wasser in die Vorrichtung durch das innere
Röhrchen (26a) des oder jedes Rohrs (26) geführt wird und heißes Wasser durch das
äußere Röhrchen (26b) des oder jedes Rohrs (26) aus der Vorrichtung herausgeführt
wird.
1. Appareil de durcissement d'encre comportant un système de refroidissement entièrement
autonome, l'appareil comprenant un boîtier unique (10), dans une extrémité (12) duquel
est prévue une lampe (14), caractérisé en ce que :
le boîtier unique (10) comprend un ventilateur (24) dans l'autre extrémité (22) ; et
l'appareil comporte, défini dans celui-ci, un passage pour diriger de l'air émis à partir de la lampe (14), durant l'utilisation, sur des surfaces refroidies (28, 30) à l'intérieur du boîtier (10) vers le ventilateur (24), et comporte en outre, défini dans celui-ci, un passage supplémentaire pour diriger de l'air par-dessus des surfaces refroidies (32) à l'intérieur du boîtier (10) à partir du ventilateur (24) vers la lampe (14).
2. Appareil selon la revendication 1, dans lequel les surfaces refroidies (28, 30, 32)
à l'intérieur du boîtier sont refroidies par de l'eau canalisée à travers au moins
un tuyau (26) à l'intérieur du boîtier.
3. Appareil selon la revendication 1 ou la revendication 2, dans lequel les surfaces
refroidies (28, 30) comprennent des surfaces d'au moins un réflecteur (16, 18) qui
entoure la lampe (14) au moins partiellement.
4. Appareil selon la revendication 2 ou la revendication 3, dans lequel le ou chaque
tuyau (26) comprend des canaux distincts intérieur (26a) et extérieur (26b).
5. Appareil selon la revendication 4, dans lequel de l'eau froide est dirigée dans l'appareil
à travers le canal intérieur (26a) du ou de chaque tuyau (26) et de l'eau chaude est
dirigée hors de l'appareil à travers le canal extérieur (26b) du ou de chaque tuyau
(26).
REFERENCES CITED IN THE DESCRIPTION
This list of references cited by the applicant is for the reader's convenience only. It does not form part of the European patent document. Even though great care has been taken in compiling the references, errors or omissions cannot be excluded and the EPO disclaims all liability in this regard.
Patent documents cited in the description