GB2190742A

GB2190742A - Moisture controller for a UV monitor

Info

Publication number: GB2190742A
Application number: GB08709215A
Authority: GB
Inventors: John David Bridgen
Original assignee: Hanovia Ltd
Current assignee: Hanovia Ltd
Priority date: 1986-04-29
Filing date: 1987-04-16
Publication date: 1987-11-25
Also published as: GB8709215D0; JPS6336816A; GB8610420D0

Abstract

A UV-Monitor and a UV- irradiation container 1 have means to maintain the outside surface of a window 8 of the container free from moisture. In one embodiment, a dessicant 10 is provided in a port 2 surrounding the window and on which the UV monitor (Fig. 4, not shown) is mounted. In another embodiment (Figs. 5 and 6, not shown), pressurized, dry, oil-free air is directed into the UV monitor and port. <IMAGE>

Description

SPECIFICATION Moisture controller The invention relates to a moisture controller.

According to the invention there is provided a container comprising a viewing port and means to maintain the port substantially free of moisture on a side remote from the interior of the container.

The means may comprise dessicating means. This is a relatively simple yet effective way to control moisture.

The dessicating means may comprise a body of dessicant which substantially conforms to the internal configuration of a boundary wall of the port; with this arrangement the central area of the pkort can be left free for monitoring the interior of the container, through the port.

The dessicating means may be removably held in the port by securing means. By this arrangement the dessicating means can be removed and replaced by a fresh one when it is spent.

The complementary releasable locking means may be screw-threads.

The apparatus may be in combination with apparatus for monitoring the intensity of a light source with the container, the monitoring apparatus comprising complementary means for mounting on the port.

The mounting apparatus may include means to maintain the apparatus substantially free of moisture.

The means of the monitor may comprise a dessicant.

The monitoring apparatus may be adapted for connection with a supply of dry gas.

The source of dry gas may comprise a source of dry, oil free air.

The air may be at 3-5 p.s.i. above atmospheric pressure.

The apparatus may have a boss complementary with the port and may provide a path for air from the source to the port.

The invention may extend to a container as hereinbefore defined in conjunction with a UVmonitor adapted for mounting on the port and for maintaining the port substantially free of moisture, on a side remote from the interior of the container.

The invention may further extend to a UVmonitor adapted for mounting on the port and for maintaining the port substantially free of moisture, on a side remote from the interior of the container.

Apparatus embodying the invention is hereinafter described, by way of example, with reference to the accompanying drawings.

Figure. 1 is an exploded perspective view showing a viewing port of a container according to the invention; Figure. 2 is an end elevation of a monitor for mounting on the port; Figure. 3 is a transverse sectional elevation of a part of the monitor of Fig. 2 which is mounted on the outlet port; Figure. 4 is a view of the interior of the monitor; Figure. 5 shows a view of the interior of a second UV-monitor according to the invention; and Figure. 6 shows a view in the direction of arrow 'A' in fig. 5.

Referring to Figs 1-6 of the drawings, there is shown part of a container 1 which is in the embodiment shown for water which is to be sterilised by a UV-source (not shown) aiso within this container. Such a container 1 is often used continuously, the water to be sterilised passing continuously through it. In order to check on whether sterilisation is being effected efficienty it is usual to monitor the radiation emitted by the UV-source. To provide for such monitoring, the container 1 has a viewing port 2 in a boundary wall 3 thereof, the port 2 comprising a boss 4 integral with the wall 3 and which provides a mount for a UV-monitor 5 which can be mounted on the boss 4 for receiving radiation from the UVsource and (continuously) monitoring same.

The boss 4 is cylindrical, has an upstanding guide lug or peg 6, and a circumferential groove or recess 7 in its outer cylindrical boundary surface. Internally the boss has a window 8, of quartz, where UV-radiation is being monitored, a groove 9 in which is received a removable dessicating means 10 in the form of a toroid of permeable material enclosing a mass of dessicant such as silica gel crystals, and a locking ring 11 which is a metal annulus with a screw threaded periphery which mates with complementary screw threads 12 of the boss 4 at the end opposite the quartz window 8.

In use, a fresh toroid 10 of dessicant is held in place in the boss 4 by locking ring 11, and the UV-monitor 5 is then mounted on the boss 4 by offering it up thereto with the groove 14 and lug 6 aligned, with the screws 16 retracted. The monitor 5 is then pushed onto the lug 6, towards the container 1, until it is fully home with screws 16 over the groove 7. They are then screwed down into the groove to lock the monitor releasably onto the container 1. The monitor 5 and container 1 are then correctly aligned, with no attenuation of the light radiated from the source, the lug and groove ensuring this.UV radiation thus travels from the source, through the window 8, through the boss 4, through an iris 17 of the monitor 5 and is reflected by metal plate reflectors 18 to a convertor 19 which converts the radiation into electrical energy, which can then be measured, checked and thus provides a monitor for the intensity of the radiation emanating from the source.

The toroid 10 of dessicant absorbs moisture in the boss 4, keeping the window 8 moisture and mist-free. This in turn means that there is no scatter of absorption of the UV-radiation being monitored, so that a true reading can be made by the monitor 5. Moreover, in order to ensure that the metal reflector plates 18 are themselves maintained moisture free, there is a moisture absorber 20 in the form of an envelope of dessicant such as silica gel crystals internally of the monitor, held removably in place round the convertor 19. It is ensured that the crystals are both ends of th sachet to provide maximum exposure thereof to the atmosphere in the monitor. This again provides for an accurate reading. The absorber 20 can be replaced by a fresh one when it is spent.

The dessicant 10 can be removed by unscrewing the locking ring 11. Moreover, it can be replaced with a fresh one, or by a mask 21 for UV should the monitor not be used.

Referring now to Figs. 5 and 6 of the drawings, in which like parts are referred to by like reference numerals as compared with Fig. 4, there is shown a UV-monitor 5 which is used for monitoring the UV radiation from a container like the one described with reference to the first embodiment, not shown, which has a boss 13 which is a close-sliding fit over a boss 4 of the container. In this embodiment, the 'O'-ring is ommitted and there is no quartz window 8. The interior of the UV-monitor 5 is connected with a source of gas, in this case dry air which is oil free, and a pressure of 3-5 p.s.i. above atmospheric pressure by a tube or conduit 21 secured to the body 5 by a screw-threaded union 22. The tube 21 opens into the interior of the UV-monitor 5.

In use, the UV-monitor 5 is mounted by its boss 13 onto the boss of the container so that UV light passes from the contaioner in the direction of arrow 'X' to be reflected by the reflectors 18 and impinges on the convertor 19, as described hereinbefore. In order to keep the window 'W' moisture free, the dry, oil free air is passed under pressure into the interior of the UV-monitor via the tube or conduit 21. The air enters the optics assembly and pressurises the internal volume. The air escapes from the interior of the UV-monitor via an iris or hole 23 in an aperture plate 24 in the boss 13, and impinges on the external surface of the irradiation container or chamber.

This has the effect of preventing any moisture forming on the window 'W' surface of the container when the temperature of the container drops below the dew point, thus rendering the monitoring system free of adverse low temperature variations, and therefore ensuring accurate readings of UV-intensity emanating from the UV-source in the container.

Claims

CLAIMS:

1. A container comprising a viewing port and means to maintain the port substantially free of moisture on a side remote from the interior of the container.

2. A container according to Claim 1, the means comprising dessicating means.

3. A container according to Claim 2, the dessicating means comprising a body of dessicant which substantially conforms to the internal configuration of a boundary wall of the port.

4. A container according to Claim 3, the dessicating means being removably held in the port by securing means.

5. A container according to Claim 4, the securing means comprising a lockable ring having releasable locking means complementary to locking means of the port.

6. A container according to claim 5, the releasable complementary locking means comprising screw threads.

7. A container according to Claim 1, in combination with apparatus for monitoring the intensity of a light source with the container, the monitoring apparatus comprising complementary means for mounting on the port.

8. A container according to Claim 7, the monitoring apparatus including means to maintain the apparatus substantially free of moisture.

9. A container according to Claim 8, the means of the monitor comprising dessicant.

10. A container according to Claim 7, the monitoring apparatus being adapted for connection with a supply of dry gas.

11. A container according to Claim 10, the source of dry gas comprising a source of dry, oil free air.

12. A container according to claim 11, the air being at 3-5 p.s.i. above atmospheric pressure.

13. A container according to Claim 12, the apparatus having a boss complementary with the port and providing a path for air from the source to the port.

14. A container, substantially as hereinbefore described with reference to the accompanying drawings.

15. A container according to any preceding claim, in conjunction with a UV-Monitor adapted for mounting on the port and for maintaining the port substantially free of moisture, on a side remote from the interior of the container.

16. A UV-Monitor adapted for mounting on the port and for maintaining the port substantially free of moisture, on a side remote from the interior of the container.

17. A UV-Monitor, substantially as hereinbefore described with reference to the accompanying drawings.