GB2409032A

GB2409032A - Light transmission device for monitoring the cleanliness of a pipe

Info

Publication number: GB2409032A
Application number: GB0328799A
Authority: GB
Inventors: Douglas Ferguson Morrison; David Anthony Pleasants
Original assignee: Individual
Current assignee: Individual
Priority date: 2003-12-11
Filing date: 2003-12-11
Publication date: 2005-06-15
Also published as: GB0328799D0

Abstract

A device and method for monitoring the cleanliness of a pipe are disclosed. The device comprises a source of electromagnetic radiation 26, such as an LED, a detector 28, such as a photocell, adapted to sense light transmitted though the pipe 12 from the source 26, and control means 22, which actuates an indicator when the intensity of the sensed electromagnetic radiation falls below a pre-determined threshold intensity, thereby indicating that the pipe needs cleaning. The device is particularly useful for monitoring the cleanliness of beer lines. The transmission of light is measured in a direction that is transverse to the flow of fluid along the pipe. The indicator may be an audible indicator such as an electric buzzer 17, or a visual indicator such as an LED 18 or LCD display 16.

Description

Title- Improvements relating to the Cleaning of Pipes This invention

relates to the cleaning of pipes, and in particular to devices and methods for monitoring the cleanliness of pipes such as beer lines.

Pipes are used in many fields of technology for conveying a fluid. For example, public houses and wine bars sell beer and other beverages that are stored in barrels or other containers and pumped to a dispensing tap through pipes that are commonly referred to as beer lines.

Beer lines need to be cleaned on a regular basis in order to maintain the quality of the beer or other beverage that is transported through the beer lines and supplied to the customer. Conventionally, it is the responsibility of a landlord, manager, or other employee to clean the beer lines at regular intervals, eg every seven days. Relatively recently, monitoring devices have been developed which automatically detect that cleaning is taking place. Such devices then wait, for a pre-determined length of time after cleaning, before sounding an alarm to remind the person responsible to clean the beer lines again. The alarm will typically sound until the device detects that the beer line is being cleaned once more.

However, such devices do not take account of different circumstances that might effect the regularity with which a particular beer line should be cleaned.

The beer line is cleaned, or at least is supposed to be cleaned, according to a predetermined schedule. This means that the beer line may be cleaned less frequently than is actually desirable or in some circumstances more frequently than is actually necessary. The former case may lead to inadequate maintenance of hygiene, while the latter may be wasteful.

There has now been devised an improved device and method for monitoring the need to clean a pipe which overcome or substantially mitigate the above- mentioned and/or other disadvantages associated with the prior art.

According to a first aspect of the invention, there is provided a device for monitoring the cleanliness of a pipe, which device comprises a source of electromagnetic radiation, a detector adapted to sense electromagnetic radiation transmitted through the pipe from the source, and control means which actuates an indicator when the intensity of the sensed electromagnetic radiation falls below a pre-determined threshold intensity, thereby indicating that the pipe needs cleaning.

The device according to the invention is advantageous over the prior art principally because the cleanliness of the pipe is monitored directly, and so the device according to the invention provides a more accurate and reliable indication of when cleaning is necessary. The pipe can therefore be maintained with a standard of cleanliness that is greater than a predetermined minimum standard. Where the device is used with pipes that supply beverages to a dispensing point, the quality of the beverage can be maintained at an acceptable standard, thereby reducing the likelihood of customer dissatisfaction. In particular, because the indicator may be actuated only when the sensed intensity falls below a predetermined threshold, the device initiates cleaning as soon as cleaning is actually necessary, and not too early or too late as may be the case when cleaning is carried out according to a fixed schedule.

Although the device according to the invention may be utilised in many different fields, the device according to the invention is intended principally for use with pipes for carrying beverages, such as beer. In particular, the device according to the invention is preferably adapted for use with pipes, commonly referred to as "lines" or "beer lines", that transport beverages from a storage container, which is most likely a barrel or the like, to a dispensing tap.

The transmission of electromagnetic radiation is preferably measured in a direction that is transverse to the flow of fluid along the pipe.

The source of electromagnetic radiation and the detector of transmitted electromagnetic radiation are preferably disposed on opposite sides of the pipe. The electromagnetic radiation that is emitted by the source and sensed by the detector is of a wavelength to which the pipe and any fluid contents thereof are at least partially transparent. For convenience, the electromagnetic radiation preferably has a wavelength within the visible spectrum. Therefore, the source of electromagnetic radiation is most preferably a visible light source, such as a suitable LED. In some arrangements, a plurality of sources and detectors may be disposed around the pipe.

The detector that senses the transmitted electromagnetic radiation preferably converts the intensity of sensed electromagnetic radiation into a voltage signal.

The detector may comprise a photocell, such as a Cadmium Sulphide (CdS) photocell, or a photo-transistor, such as a silicon photo-transistor.

The control means is preferably a processing unit such as a microprocessor, and is preferably adapted to receive a voltage signal from the detector that corresponds to the intensity of transmitted light sensed by the detector. The control means may calculate the relative intensity of the sensed electromagnetic radiation from the voltage signals received from the detector.

In this case, the control means actuates an indicator when the intensity of the calculated intensity falls below a pre-determined threshold intensity.

Alternatively, the control means may simply actuate an indicator when the voltage signal received from the detector passes through a pre-determined threshold voltage which corresponds to the pre-determined threshold intensity.

Suitable indicators include audible indicators, such as an electric buzzer, and visual indicators, such as an LED or an LCD display. Where an LCD display is used, the LCD display preferably also communicates other information to the user. Such information might include the number of days since the pipe was last cleaned, the date of the last clean, and/or the duration of the last clean.

The LCD display may be remotely connected to the monitoring device, as discussed below, so as to be easily visible to the user.

The device preferably includes means for storing intensity or voltage data.

The control means may also include means for outputting stored and/or real- time data to an external device, such as a laptop computer or a remote LCD display. The stored and/or real time data may be outputted to an external device directly or via a suitable network. Suitable networks include a Local Area Network (LAN), a Wide Area Network (WAN) and the internet. A monitoring device is preferably provided for each beverage that is served in a particular establishment and, in this case, the devices are preferably able to communicate with one another as well as an external device via the network.

The device preferably includes means for setting the threshold intensity for a particular pipe and fluid. This may involve manually monitoring the cleanliness of the pipe to a minimum acceptable level and selecting the intensity at that level as the threshold. Alternatively, the threshold may be set at a particular proportion of the intensity measured when the pipe is clean, or a particular deviation from that intensity.

The device according to the invention preferably includes an internal pipe adapted to form part of the pipe with which the device is to be used. The internal pipe preferably has a pair of open ends such that the device can be inserted into an opening in an existing pipe. Most preferably, an existing pipe is cut and the pair of open ends of the internal pipe are connected to the open cut ends of the existing pipe. Alternatively, the device according to the invention is adapted to operably engage the existing pipe with which the device is to be used without interrupting the existing pipe.

According to a further aspect of the invention, there is provided a method of monitoring the cleanliness of a pipe, which method comprises the steps of: 1' (a) providing a source of electromagnetic radiation adjacent a portion of the pipe that is at least partially transparent to the electromagnetic radiation; (b) sensing electromagnetic radiation transmitted across the pipe from the source; and (c) actuating an indicator when the intensity of the sensed electromagnetic radiation falls below a pre-determined threshold intensity, thereby indicating that the pipe needs cleaning.

The method according to the invention preferably utilises a detector as described above to sense electromagnetic radiation transmitted through the walls of the pipe from the source, and preferably utilises control means as described above to actuate an indicator when the intensity of the sensed electromagnetic radiation falls below a pre-determined threshold intensity.

Most preferably, the method according to the invention utilises a device as described above.

Another feature of the present invention is based on the observation that different beverages passing along the beer line exhibit different light transmission characteristics. After appropriate calibration, the transmission may therefore be used to distinguish between different beverages and cleaning fluid. Recordal of the transmission level as a function of time can therefore provide a record of the usage of the pipe (in terms of the different types of beverage that are passed along it, and the frequency and duration of the cleaning operations).

Thus, the method according to the invention preferably includes the steps of comparing the measured transmission levels with transmission levels for a plurality of different fluids, and determining the nature of the fluid present in the pipe as a function of time.

The invention will now be described in greater detail, by way of illustration only, with reference to the accompanying drawings, in which Figure 1 is a front view of a monitoring device according to the invention which is coupled to a beer line; Figure 2 is a schematic diagram of the monitoring device; and Figure 3 is a graph illustrating the variation in the intensity of light, T. transmitted from a light source to a photocell, which both form part of the monitoring device, over time, t, during use.

Referring firstly to Figure 1, the monitoring device comprises a generally rectangular housing 10, an LCD screen 16, an alarm 17, an LED indicator 18 and an internal pipe 12 (not visible in Figure 1) that extends along the length of the device and terminates at each end with a connector 14. The housing 10 is moulded in a plastics material and comprises two cooperating halves that together define an internal enclosure through which the pipe 12 extends.

Each of the connectors 14 is adapted to engage an open end of a beer line 20.

In order to install the monitoring device, an existing beer line 20 is cut and each of the connectors 14 is engaged with one of the open ends of the cut beer line 20. The connectors 14 form a sealed connection between the pipe 12 of the monitoring device and the beer line 20 such that the pipe 12 forms part of the beer line 20.

Referring now also to Figure 2, the pipe 12 of the monitoring device is a cylindrical tube of extruded plastics material that is transparent to visible light.

The internal enclosure of the monitoring device contains a microprocessor 22, an LED 26 and a photocell 28. The monitoring device is powered from the mains supply using a low voltage DC transformer. However, the internal enclosure includes a battery 24 to provide backup power for the monitoring device.

The LED 26 and photocell 28 are disposed at opposite sides of the pipe 12 so that at least some of the light emitted by the LED 26 is transmitted through the walls and fluid content of the pipe 12, and is received by the photocell 28. The electrical resistance of the photocell 28 varies inversely proportionally with the intensity of the light received by the photocell 28. In this way, the microprocessor 22 receives voltage data from the varying resistance of the photocell 28, which in turn corresponds to the intensity of light transmitted from the LED 26 to the photocell 28.

The microprocessor 22 receives, stores and processes the voltage data received from the photocell 28, and controls the LCD screen 16, the alarm 17 and the indicator LED 18 accordingly, as described more fully below. The monitoring device is also provided with an output serial port 30 (not visible in Figure 1) which can be used to output either stored, or realtime, data from the microprocessor 22 to an external device, such as a laptop computer (not shown in the Figures), via a direct connection or a suitable network, such as a Local Area Network (LAN), a Wide Area Network (WAN) or the internet.

The microprocessor 22 is calibrated for a particular beverage when the pipe 12 is clean, and then alerts the user that the beer line 20 needs cleaning when the intensity of light transmitted from the LED 26 to the photocell 28 falls below a pre-determined threshold intensity that is determined during calibration. The user is alerted that the beer line 20 needs cleaning by the LCD screen 16, the alarm 17 and the indicator LED 18.

The alarm 17 is actuated continuously whilst the intensity of light transmitted from the LED 26 to the photocell 28 is below the threshold cleaning intensity, thereby encouraging a fast response from the person responsible. The indicator LED 18 is a three colour LED, and is controlled by the microprocessor 22 to emit different coloured light to indicate the status of the monitoring device and the beer line 20. Green light is emitted so long as the transmitted intensity exceeds the threshold cleaning intensity and the beer line 20 is not yet in need of cleaning. A red light is emitted when the transmitted intensity is less than the threshold cleaning intensity and the beer line is in need of cleaning.

Finally, an amber light is emitted when the transmitted intensity is increasing, indicating that the beer line is being cleaned.

The LCD screen 16 is controlled by the microprocessor 22 to display realtime and stored information regarding the beer line 20. During normal use, the LCD screen 16 displays an indication of the cleanliness of the beer line 20, an estimation of when the next cleaning operation is expected to be due, the number of days since the last cleaning operation was carried out, and the date and duration of the last cleaning operation. When the transmitted intensity falls to a level less than the threshold cleaning intensity, the LCD screen will indicate that cleaning is now due, and when the transmitted intensity increases as the beer line is cleaned, the LCD screen will display an indication of the improving cleanliness of the beer line 20 and the duration of the current cleaning operation.

Figure 3 illustrates a typical variation in the intensity of light, T. transmitted from the LED 26 to the photocell 28 over time, t, during normal use. At time A, the pipe 12 and beer line 20 are clean, and the beer line 20 is charged with a particular beverage. The microprocessor 22 takes a reading of the intensity of light transmitted from the LED 26 to the photocell 28 at regular intervals, eg every 60 seconds.

During normal use of the beer line 20, the measured light intensity T will gradually fall. This may be due to increased opacity (eg cloudiness) of the beer or other beverage passing through the beer line 20 and/or deposition of material on the internal surface of the pipe 12 of the monitoring device. The reduction in the transmitted intensity is shown in Figure 3. Eventually, at time B. the transmitted intensity will equal the cleaning threshold intensity 30. The microprocessor 22 will then alert the user that the beer line 20 needs cleaning by activating the alarm 17, the indicator LED 18 and the LCD screen 16, as described above. On commencement of cleaning of the beer line 20, at time C, the intensity of light transmitted will increase, because the cleaning fluid will generally be more transparent that the beverage with which the beer line 20 was charged, and will continue to increase as the beer line 20 is cleaned.

Once the transmitted intensity has increased above the cleaning threshold intensity 30, the alarm 17 will be deactivated. The LCD screen 16 and indicator LED 18 will indicate that cleaning is in process.

The intensity of light transmitted will increase up to a maximum intensity, at time D, that corresponds to a clean beer line 20 and pipe 12. The microprocessor 22 will then inform the user via the LCD screen 16, and indicator LED that the beer line 20 is clean, as described above. The beer line and pipe 12 is then flushed with water to remove the cleaning fluid from the beer line 20 and pipe 12. Finally, at time E, the beverage is returned to the beer line 20 so that normal use can recommence once the beer line 20 and pipe 12 have been fully charged with the beverage, at time F. I'd /

Claims

Claims 1. A device for monitoring the cleanliness of a pipe, which device

comprises a source of electromagnetic radiation, a detector adapted to sense electromagnetic radiation transmitted through the pipe from the source, and control means which actuates an indicator when the intensity of the sensed electromagnetic radiation falls below a pre-determined threshold intensity, thereby indicating that the pipe needs cleaning.
2. A device as claimed in any Claim1, wherein the transmission of electromagnetic radiation is measured in a direction that is transverse to the flow of fluid along the pipe.
3. A device as claimed in Claim 2, wherein the source of electromagnetic radiation and the detector of transmitted electromagnetic radiation are disposed on opposite sides of the pipe.
4. A device as claimed in any preceding claim, wherein the electromagnetic radiation that is emitted by the source and sensed by the detector is of a wavelength to which the pipe and any fluid contents thereof are at least partially transparent.
5. A device as claimed in Claim 4, wherein the electromagnetic radiation has a wavelength within the visible spectrum.
6. A device as claimed in Claim 5, wherein the source of electromagnetic radiation is an LED.
7. A device as claimed in any preceding claim, wherein a plurality of sources and detectors are disposed around the pipe.
8. A device as claimed in any preceding claim, wherein the detector that senses the transmitted electromagnetic radiation converts the intensity of sensed electromagnetic radiation into a voltage signal.
9. A device as claimed in Claim 8, wherein the detector comprises a photocell.
10. A device as claimed in Claim 9, wherein the photocell is a Cadmium Sulphide (CdS) photocell.
11. A device as claimed in Claim 8, wherein the detector comprises a photo-transistor.
12. A device as claimed in Claim 11, wherein the photo-transistor is a silicon photo-transistor.
13. A device as claimed in any preceding claim, wherein the control means is a microprocessor.
14. A device as claimed in Claim 13, wherein the microprocessor is adapted to receive a voltage signal from the detector that corresponds to the intensity of transmitted light sensed by the detector.
15. A device as claimed in Claim 14, wherein the microprocessor calculates the relative intensity of the sensed electromagnetic radiation from the voltage signals received from the detector.
16. A device as claimed in Claim 14, wherein the microprocessor actuates an indicator when the voltage signal received from the detector passes through a pre-determined threshold voltage which corresponds to the predetermined threshold intensity.
17. A device as claimed in any preceding claim, wherein the indicator is an audible indicator.
18. A device as claimed in Claim 17, wherein the audible indicator is an electric buzzer.
19. A device as claimed in any one of Claims 1-16, wherein the indicator is a visual indicator.
20. A device as claimed in Claim 19, wherein the visual indicator is an LED.
21. A device as claimed in Claim 19, wherein the visual indicator is an LCD display.
22. A device as claimed in Claim 21, wherein the LCD display also communicates other information to the user.
23. A device as claimed in Claim 21 or 22, wherein the LCD display is remotely connected to the monitoring device.
24. A device as claimed in any preceding claim, wherein the device includes means for storing intensity or voltage data.
25. A device as claimed in any preceding claim, wherein the control means includes means for outputting stored and/or real-time data to an external device.
26. A device as claimed in Claim 25, wherein the external device is a laptop computer or a remote LCD display.
27. A device as claimed in Claim 25, wherein the stored and/or real time data is outputted to an external device directly or via a network.
28. A device as claimed in Claim 27, wherein the network a Local Area Network (LAN), a Wide Area Network (WAN) or the internet.
29. A device as claimed in any preceding claim, which includes the means for setting the threshold intensity for a particular pipe and fluid.
30. A device as claimed in any preceding claim, which includes an internal pipe adapted to form part of the pipe with which the device is to be used.
31. A device as claimed in Claim 30, wherein the internal pipe has a pair of open ends such that the device can be inserted into an opening in an existing pipe.
32. A device as claimed in Claim 1, which is adapted to operably engage the existing pipe with which the device is to be used without interrupting the existing pipe.
33. A method of monitoring the cleanliness of a pipe, which method comprises the steps of: (a) providing a source of electromagnetic radiation adjacent a portion of the pipe that is at least partially transparent to the electromagnetic radiation; (b) sensing electromagnetic radiation transmitted across the pipe from the source; and (c) actuating an indicator when the intensity of the sensed electromagnetic radiation falls below a pre-determined threshold intensity, thereby indicating that the pipe needs cleaning.
34. A method as claimed in Claim 33, which includes a further step of comparing the measured transmission levels with transmission levels for a plurality of different fluids, and determining the nature of the fluid present in the pipe as a function of time.
35. A method as claimed in Claim 33 or 34, wherein the source of electromagnetic radiation is provided by positioning a device according to Claim 1 adjacent to the pipe.
36. A pipe to which is fitted a device as claimed in any one of Claims 132.
37. A pipe as claimed in Claim 36, which is for the transport of beverages.
38. A pipe as claimed in Claim 37 which is for the transport of beverages from a storage container to a dispensing tap.
39. A pipe as claimed in any one of Claims 36-38, wherein the device includes an internal pipe, and the device is fitted by cutting the existing pipe and inserting the open ends of the internal pipe into the cut ends of the existing pipe.
40. A method of monitoring the cleanliness of a pipe substantially as hereinbefore described.
41. A device for monitoring the cleanliness of a pipe substantially as hereinbefore described with reference to the drawings.