GB2190994A

GB2190994A - Ultraviolet irradiation device

Info

Publication number: GB2190994A
Application number: GB08707352A
Authority: GB
Inventors: Jong Willem Errit De; Michael Werner
Original assignee: Philips Gloeilampenfabrieken NV
Current assignee: Koninklijke Philips NV
Priority date: 1986-04-04
Filing date: 1987-03-27
Publication date: 1987-12-02
Also published as: SE8701354L; AT400107B; NL8600861A; BE1000049A3; GB8707352D0; DE8704271U1; SE8701354D0; GB2190994B; ATA79787A

Abstract

An ultraviolet irradiation device has a housing (1) in which a number of juxtaposed low-pressure mercury vapour discharge lamps (2,3,4,5) are arranged which emit ultraviolet radiation during operation. The lamps have lamp bases at one end only, the lamps being, for example, "PL" type lamps, and holders (9) for the lamp bases are located side by side towards one end of the housing (1). <IMAGE>

Description

SPECIFICATION Ultraviolet irradiation device The invention relates to an ultraviolet irradiation device having a housing in which a number of juxtaposed low pressure mercury vapour discharge lamps emitting ultraviolet radiation during operation are arranged.

A device of this type is known from German Gebrauchsmuster 8203064 and is used for medical or biological purposes, particularly as a facial irradiator for direct pigmentation of the human skin (tanning without erythema) in which the face or the upper part of the body is exposed for some time to long wave ultraviolet radiation (UV-A radiation). The device comprises a synthetic material housing which is open on the front side and which accommodates a number of parallel arranged tubular lamps. The discharge vessel of each lamp is provided at both ends with a lamp base having current connection pins which are secured in oppositely located lamp holders present near the two ends of the housing.

The housing of the known device requires comparatively many lamp holders and has an extensive wiring system for the connection to the electric stabilisation ballasts and the starters. Such ballasts are provided, for example, in a base connected to the housing. In another embodiment these components are incorporated in the housing itself. In the known device a relatively large number of ballasts is required for which extra measures are necessary to inhibit intense heat development during their operation.

The invention has for its object to provide an irradiation device in which the number of required ballasts and lamp holders is reduced, which can be manufactured in a simple manner and is easy to handle.

To this end an irradiation device of the type described in the opening paragraph according to the invention is characterized in that the lamps are provided with a lamp base at only one end, the discharge vessel of a lamp comprising at least two parallel juxtaposed tube parts which are connected together, said lamp bases being mounted in holders which are located side by side towards one end of the housing.

The irradiation device according to the invention is compact and has a relatively high radiation efficiency. The number of required lamp holders, compared to the known device, is greatly reduced. Mounting is simple. In a practical embodiment the lamp holders are combined on one chassis.

The housing of the irradiation device requires relatively few ballasts and starters and the use of an extensive and complicated wiring system for connecting the lamp holders to starters, stabilisation ballasts and the mains is avoided. Furthermore, because the lamps have their bases at one end only, they can easily be mounted by a user into the holders. The housing of the device according to the invention has a simple shape.

The said lamps may comprise, for example, a U-shaped discharge tube comprising two parallel tube parts joined by a U-bend or they may be in the form of "PL"-lamps described in USP 4,374,340. In a further embodiment the lamp comprises four parallel co-planar tube parts which are connected together by means of coupling joints. Such a lamp is also provided with the said lamp base and is described in USP 4,374,340. The inner wall of the discharge vessel of the lamps is provided with a luminescent layer emitting ultraviolet radiation and comprising, for example, a luminescent material based on lead activated barium disilicate emitting UV-A radiation. For purposes other than for tanning the device is provided with lamps having a luminescent layer emitting UV-B radation (for example, for treating skin diseases) or with a layer emitting UV C radiation (for example, for biological uses).

In a particular embodiment the tube parts of the lamps are co-planar. Alternatively, the lamps may be arranged in a sight curve. In both cases, a large radiating surface is achieved.

In a further embodiment of the irradiation device according to the invention a reflector is present behind the lamps in the housing. The efficiency of the irradation device is then high.

An embodiment of the device according to the invention will now be described in greater detail with reference to the accompanying drawing.

This drawing shows the irradiation device in the form of a UV-A table solarium suitable for irradiation of the face or of the upper part of the body.

The device comprises a synthetic material housing 1 which is open on its front side and which can be placed on, for example, a table by a user. The housing accommodates four vertically positioned low pressure mercury vapour discharge lamps 2, 3, 4 and 5 ("PL"lamps) which emit UV-A radiation (315-400 nm) during operation. Each lamp has a discharge vessel with two parallel and juxtaposed tube parts (for example, 2a and 2b) which are connected together by means of a coupling joint (2c) near the upper end. The electrodes (6, 7) are present at the lower end of the tube parts (2a, 2b) so that a U-shaped discharge path is present during operation of the lamp. Relatively cool areas in the discharge vessel are present at the upper ends of the tube parts for controlling the mercury vapour pressure during operation of the lamp, which notably in a compact housing is very advantageous.

Each lamp (2, 3, 4 and 5) has only one lamp base, 8 which is located on the lower side of the lamp. Such a lamp base provides electrical connection with the electrodes 6 and 7, and may comprise a starter, and is described in USP 4,374,340. The lamp bases are connected and carried in respective holders cooperating therewith, such as 9, which are arranged side by side on a chassis located at the lower end of the housing. A reflector 10 is present behind the lamps in the housing.

The eight tube parts of the four lamps may be co-planar, as shown, or may be arranged in a slight curve plane, the reflector 10 being shaped accordingly.

-Because lamp holders at the upper end of the housing are not required the housing is comparatively shallow.

The lamps 2 through 5 have a length of approximately 30 cm. The total length of the discharge path is then approximately 55 cm.

The tube parts have an internal diameter of approximately 16 mm. The inner wall of the two tube parts is coated with a luminescent layer comprising a luminescent material based on lead-activated barium disilicate. The lamps have a power of 24 W.

Claims

1. An ultraviolet irradiation device having a housing in which a number of juxtaposed lowpressure mercury vapour discharge lamps emitting ultraviolet radiation during operation are arranged, characterized in that the lamps are provided with a lamp base at only one end, the discharge vessel of a lamp comprising at least two parallel juxtaposed tube parts which are connected together, said lamp bases being mounted in holders which are located side by side towards one end of the housing.

2. An irradiation device as claimed in Claim 1, characterized in that the tube parts of the lamps are co-planar.

3. An irradiation device as claimed in Claim 1, characterized in that the lamps are arranged in a slight curve.

4. An irradiation device as claimed in Claim 1, 2 or 3, characterized in that a reflector is present behind the lamps in the housing.

5. An ultraviolet irradiation device substantially as hereinbefore described with reference to, and as shown in, the accompanying drawing.