GB2447628A

GB2447628A - Ultrasonic nebulising system for evaporating the waste water created by a refrigerated cabinet during defrost

Info

Publication number: GB2447628A
Application number: GB0705172A
Authority: GB
Inventors: Kevin Gulliver; Richard Harding; Chris Woollett
Original assignee: Individual
Current assignee: Individual
Priority date: 2007-03-17
Filing date: 2007-03-17
Publication date: 2008-09-24
Also published as: GB0705172D0

Abstract

An ultrasonic nebulising system using a series of switched low voltage alternating current (AC) controlled transducers 'M' inside an atomising chamber 'C' to evaporate and vent, with the assistance of a fan 'J', through an outlet to atmosphere 'D' the waste water discharged from a refrigerated display cabinet during defrost. The system can be used as a direct replacement for a conventional drip tray and rod heating element. Alternatively, the system may be used as a direct replacement for a pump unit. Preferably, the number of ultrasonic nebulising modules fitted to the atomising chamber is proportional to the discharge rate of water produced during defrosting. The switching of the transducers may be controlled by a horizontally mounted float switch with a pivoting actuator magnet and reed switch, a vertically mounted float switch 'G' with a magnet and reed switch, or an optical liquid level sensor. Preferably, the outlet is ducted to allow the nebulised water particles to pass through a condenser coil to reduce the discharge pressure of a compressor unit. Direct current (DC) controlled transducers may be fitted to the atomising chamber. An ultraviolet lamp 'F' may be fitted to the outlet vent for sterilisation purposes. Preferably, the refrigerated display cabinet comprises a chilled or freezer cabinet suitable for food, drinks or medication. In use, the system provides an efficient energy saving method for dealing with the problem of evaporating the waste water discharged from a refrigerated cabinet after a defrost cycle; the system provides a self contained direct replacement for the heating element and evaporation drip tray that is typically found in commercial refrigerated display cabinets.

Description

BOND ULTRASONIC NEBULISER SYSTEM

DESCRIPTION

BACKGROUND OF THE INVENTION

001. Throughout this description the Bond Ultrasonic Nebuliser system will be referred to as uThe BUN sYstem" 002. The BUN system is predominately marketed at the Supermar$cet sector and other independent retailers as an alternative to traditional refrigerated cabinet drainage.

STATEMENT OF INVENTION

003.The BUN system was primarily invented as a self contained direct replacement of a heating element and evaporation tray / drip tray that is typically used fl refrigerated display cabinets to evaporate waste water discharged after the cabinet has completed a defrost cycle 004. The BUN system was invented and tested as an energy efficient means of dealing with the problem of water displacement (003) throughout the refrigerated display cabinet market. This includes Multi deck, Half Glass Door, Well, Full Glass Door, Roll In cabinets, Deli counters on remote and integral applianc, low and high temperature

ADVANTAGES

005. Heaters traditionally fitted to refrigerated cabinets for evaporation purposes are based around 900 watt to I Kilowatt. The BUN system operates using 10% of the energy required to run these traditional rod heaters.

INTRODUCTION TO DRAWlNc3s

006. Figure 1 shows a basic example of the atomisation chamber construction venting to atmosphere.

007. Figure 2 shows a basic example of the atomisation chamber construction venting to atmosphere with the addition of an ultra violet light.

008. Figure 3 shows a basic example of the atomisation chamber construction being ducteci back over the condenser coil.

009. Figure 4 shows a basic example of the atomisation chamber construction being ducted back over the condenser coil with the addition of an ultra violet light.

010. Key to reference letters on drawing: (A) Cabinet drainage (B) Atomising chamber inlet (C) Atomising chamber (0) To Atmosphere (E) Atomising chamber Outlet vent (F) Ultraviolet light (G) Float switch (H) Nebulisecj water particles (I) Direction of Air flow (J) Fan (K) Atomising chamber Drainage outlet (L) Transducer drive circuit board (M) Transducer (N) Transformer (0) Atomising chamber inlet vent (P) Power supply (Q) Duct

DETAILED DESCRIPTION

011. The BUN system uses a vessel as an atomisation chamber (C)to collect the water that is discharged through the atomising chamber inlet (B) from the refrigerated display cabinets drainage system (A) during the cabinets defrost period. The water discharged form the cabinet is melted ice (demineralised water) that has formed on the evaporator coil during normal operation.

012. The atomising chamber (C) used to collect the water is sized accordingly against the drainage output (A) requirement of the refrigerated display cabinet.

013. The base of the atomlslng chamber (C) has a series of ultrasonic transducers (M) mounted to it.

The number of transducers (M) used in each unit is proportional to the size of the atomising chamber (C) and the cabinets drainage (A) output.

014. A float switch I water level sensor ((3) is also attached to the base of the atomising chamber (C), ensuring that the fransduce, (M) always have adequate water coverage and are only in operation when required.

015. Once the float switch (G) has been activated by an adequate amount of water the power supply (P) energises the drive circuit boards (L) via the transformer (N). The drive circuit boards (1) now energise the transducers (M) and the process of nebubsation begins (020).

016. During the process of nebulisatjon a low wattage blow fan (J) creates air turbulence (I) across the top of the atom ising chamber (C) which causes the nebulised water particles (H) to vent Out of the atomising chamber (C) through the outlet valve (E) and evaporate into the atmosphere (D) quickly and efficiently.

017. The nebulieed water particles (ii) can be directed through the condenser coil of the refrigerated cabinet for increased performance and improved life expectancy of the compressor unit (022).

018. The base of the atomising chamber (C) is fitted with a small drainage outlet (K) for maintenance Purposes.

019. Dependa on the type of refrigerated cabinet the system is fitted to the fan (J) can be replaced with a draw blade to extract the nebuliseci water particles (H) through a duct (Q) and then on to the condenser as per (017). This arrangement is shown in figure 3 and 4.

020. Figure 2 and 4 show the addition of an ultraviolet fight (F) which provides ultraviolet sterilisation to any Stored water.

IECHINCAL UNDERSTANDING OF HOW IT WORKS

021. The BUN system uses ultrasonic nebulising modules and transducers to create Nebulising.

These modules are electronic oscillator Circuits that power the transducers at high frequency. The transducers are matched at their resonant frequency and generate a mechanical vibration. Water inside the atomisatjon chamber is in direct contact with the vibrating faces I plates of the transducers.

This causes the water to vibrate. Because of fts mass, the water is unable to follow the high frequency oscillation of the transducers and cavitation occurs. When this process begins below the surface of the water, refractej capillary waves are generated, throwing off a cool dense cloud / mist of water particles.

022. To prevent the evaporated water particles from condensing back to a liquid form, a low wattage fan is use to blow out the evaporated water through a vent or Is drawn through a ducting system, out of the atomising chamber.

023. The dense cloud! mist of nebulised water particles created as a result of nebulising has a cooling effect whIch If harnessed can be re-directed to flow across the face of the condenser coil. This cooling effect will help the condenser reject the heat gained from the load within the refrigerated area. This will therefore due to the pressure I temperature relationship of the refrigerant reduce the discharge pressure from the compressor, therefore prolonging it's life and reducing it's running cost.

Claims

(LAJMS 1. An ultrasonic nebuhsing system, using a series of switched

low voltage AC controfled transducers inside an atomising chamber to evaporate and vent, fan assisted, through an outlet to atmosphere the waste water discharged from a refrigerated display cabinet during defrost, as a direct replacement of a rod heating element and drip tray.
2. An ultrasonic nebuliser system according to claim 1, in which the system is a direct replacement of a pump unit.
3. An ultrasonic nebuiiser system according to claim 1, in which the number of Ultrasonic Nebulising modules fitted to the atomising chamber is proportional to the discharge rate of water produced during the defrost.
4. An ultrasonic nebuliser system according to claim 1, in which the switching of the transducers is controlled by a horizontally mounted float switch with pivoting actuator magnet and reed switch.
5. An ultrasonic nebuliser system according to claim 1, in which the switching of the transducers is controlled by a vertically mounted float switch with magnet and reed switch.
6. An ultrasonic nebuliser system according to claim 1, in which the switching of the transducers is controlled by an optical liquid level sensor.
7. An ultrasonic nebuliser system according to claim I * in which the outlet is ducted to allow the nebuijsed water particles to pass through the condenser coil to reduce the discharge pressure of the compressor unit.
8. An ultrasonic nebuliser system according to claim 1, in which DC controlled transducers are fitted to the atomising chamber.
9. An ultrasonic nebuliser system according to claim 1, in which an ultraviolet lamp is fitted to the vent for sterilisation purposes.
10. An ultrasonic nebuliser system according to claim 1, in which the term refrigerated display cabinet is defined as chilled and frozen cabinets, remotely and integrally operated, used for food, drinks or medication purposes.