GB2466990A

GB2466990A - Refrigerated food storage unit with a baffle plate to disperse air flow evenly across a chilling unit

Info

Publication number: GB2466990A
Application number: GB0900803A
Authority: GB
Inventors: Kenneth Thomas Stewart; Colin William Stewart; Keith Anthony Stewart
Original assignee: Individual
Current assignee: Individual
Priority date: 2009-01-19
Filing date: 2009-01-19
Publication date: 2010-07-21
Also published as: GB0900803D0

Abstract

A refrigerated food storage unit 1 has a refrigeration compartment 7 comprising a chilling unit 17, a tangential fan unit 19, an air circulation duct 21, and a baffle plate 31 which is located between the fan unit and the chilling unit. The baffle plate 31 has a series of apertures [see e.g. Figure 6] which help to disperse concentrated air flows leaving the fan unit 19 thus creating a more uniform chilling of the air as it passes across the chilling unit 17 before being delivered to a food storage compartment 5. The cabinet 3 also has a food storage compartment 5, a transparent display shield 9 covering the food storage compartment and an opening 11 in the display shield adjacent the rear 29 of the cabinet 3 to allow access to the food storage compartment 5. An air intake 23 is located at the front 25 of the unit to allow air to flow into the air circulation duct 21 whilst an air discharge outlet 27 is located at the rear of the cabinet to allow chilled air to exit the circulation duct and pass into the food storage compartment 5. The chilling unit 17 comprises a cooling coil having a plurality of overlapping vertically arranged fins mounted side by side across the entire width of the cabinet. The baffle plate may be of a two part construction [31a, 31b, Figure 6], and may be curved [see Figure 9].

Description

"A Refrigerated Food Storage Unit"

Introduction

This invention relates to a refrigerated food storage unit of the type comprising a cabinet having a food storage compartment, a refrigeration compartment, a transparent display shield covering the food storage compartment and an opening in the display shield adjacent the rear of the cabinet to allow access to the food storage compartment.

Refrigerated food storage units are commonly found in convenience stores and other premises where prepared food is sold. For example, refrigerated food storage units are often used to store foodstuffs such as cold meats and other sandwich fillings that must be kept chilled in order to avoid the foodstuffs becoming spoilt. An example of one such refrigerated food storage unit is that disclosed in European Patent No. EP 1 410 746. A further example of a refrigerated food storage unit is that disclosed in European Patent Application No. EP 1 855 071. Both EP 1 410 746 and EP 1 855 071 disclose a refrigerated food storage unit comprising a cabinet having a food storage compartment, a refrigeration compartment, a transparent display shield covering the food storage compartment so that customers may view the foodstuffs in the food storage compartment and an opening in the display shield adjacent the rear of the cabinet to allow an employee of the convenience store access to the foodstuffs so that they may prepare a sandwich or other food item with the foodstuffs contained in the food storage compartment. The refrigeration compartments comprise a chilling unit, a fan unit and an air circulation duct. The fan unit is used to circulate air over the chilling unit and then deliver that air over the foodstuffs in the food storage compartment. The object is to keep the foodstuffs in the food storage compartment chilled at a temperature of the order of approximately 4°C.

There are however problems with the known refrigerated food storage units. One of the problems with the known refrigerated food storage units is that they tend to be relatively noisy. This is due mainly to the use of radial fans in the refrigerated food storage units. It is possible to reduce the noise produced by the unit by using tangential fans instead of radial fans.

However, there is a problem associated with the use of tangential fans also in that they tend to produce a strong directional airflow and this has a tendency to cause uneven cooling of the foodstuffs. There is a tendency for the refrigerated food storage unit to develop so-called hot spots and cold spots within the food storage compartment in which the temperature is significantly above or below the desired chilling temperature respectively. It is not uncommon for there to be hot spots or cold spots with a variance of � 5 ° from the desired chilling temperature in many of the known types of refrigerated food storage units, It has been found that in conditions where the ambient temperature can be as high at 30°C, hotspots in the food storage compartment in locations most remote from the incoming flow of chilled air can be as high as 12°C. This can cause foodstuffs to spoil and can prove a health and safety risk.

Various refrigerated food storage units have been proposed that incorporate a tangential fan, German Patent Application No. DE 19548377 describes a cold display counter which has a tangential fan arranged at the front of the cabinet, a chiller and associated guide channels between the fan and the chiller, UK Patent Application No. GB 2112511 and Japanese Patent Application No. JP 7151445 both show an open fronted refrigerated display cabinet with a tangential fan arrangement.

Dutch Patent Application No. NL 8802886, Swiss Patent Application No. CH 658372 and UK Patent Application No, GB 2017285 all disclose various embodiments of refrigerated display cabinets. FR 2859086 shows a hot food storage cabinet which includes a transparent display shield and associated heat exchange unit, a tangential fan and a diffuser. The diffuser is located downstream of both the fan and the heat exchange unit.

One way of attempting to overcome the problem associated with the use of tangential fans is to increase the fan speed and thereby increase the flow of air across the foodstuffs. However, this can increase the amount of noise produced by the fans and furthermore the increased airflow has a tendency to dry out the foodstuffs thereby having a detrimental affect on the organoleptic properties of the foodstuffs.

It is an object therefore of the present invention to provide a refrigerated food storage unit that overcomes at least some of the problems with the known units.

Statements of Invention

According to the invention there is provided a refrigerated food storage unit comprising: a cabinet having a food storage compartment, a refrigeration compartment, a transparent display shield covering the food storage compartment and an opening in the display shield adjacent the rear of the cabinet to allow access to the food storage compartment; the food storage compartment comprising a compartment floor suitable for reception of food in containers; the refrigeration compartment comprising a chilling unit, a fan unit and an air circulation duct; the air circulation duct comprising an air charging inlet located adjacent the front of the cabinet and in fluid communication with both the air circulation duct and the food storage compartment, and an air discharge outlet located adjacent the rear of the cabinet and in fluid communication with both the air circulation duct and the food storage compartment; the fan unit comprising a tangential fan mounted in the air circulation duct adjacent to the air charging inlet, the fan being operable to circulate air in the cabinet by drawing air into the air circulation duct of the refrigeration compartment from the food storage compartment through the air charging inlet, driving the air along the air circulation duct, and forcing the air back out of the refrigeration compartment to the food storage compartment through the air discharge outlet; the chilling unit comprising a cooling coil mounted in the air circulation duct adjacent to the air discharge outlet, the cooling coil having a plurality of substantially parallel, overlapping, vertically arranged fins mounted side by side and extending substantially across the entire width of the cabinet; the refrigeration compartment further comprising a baffle plate mounted in the air circulation duct intermediate and spaced apart from the fan and the chilling unit; the baffle plate comprising a plurality of spaced apart apertures therein for through passage of air, the spaced apart apertures being arranged about the baffle plate to disperse the concentrated flow of air from the fan across the entire width of the air circulation duct downstream of the baffle plate and prior to the air coming into contact with the cooling coil thereby distributing all of the air from the fan evenly across the cooling coil.

By having such a refrigerated food storage unit with a baffle plate mounted in the air circulation duct intermediate and spaced-apart from the fan and the chilling unit, the air coming from the fan is distributed evenly across the width of the refrigerated unit before coming into contact with the chiller unit. This provides a more uniform flow of air throughout the unit, improved refrigeration of the air as it passes over the chiller unit and a more uniform cooling temperature throughout the entire cabinet.

In one embodiment of the invention there is provided a refrigerated food storage unit in which the plurality of apertures are uniform in size and the number of apertures in an area of the baffle plate is chosen to regulate flow of air through the baffle plate in that area.

In another embodiment of the invention there is provided a refrigerated food storage unit in which there are provided a plurality of apertures of different sizes with respect to each other and the size of the apertures in an area of the baffle plate are chosen to regulate flow of air through the baffle plate in that area.

In a further embodiment of the invention there is provided a refrigerated food storage unit as claimed in any preceding claim in which the baffle plate is arcuate in shape. Preferably, the baffle plate has a depth of curvature of the order of 0.1 metres. The length of the baffle plate from end to end is of the order 0.5 metres.

Preferably, the baffle plate will have a depth of curvature of the order of 20% of the length of the baffle plate.

In one embodiment of the invention there is provided a refrigerated food storage unit in which there are provided a pair of baffle plates mounted side by side in the air circulation duct and spaced apart from each other. Preferably, the baffle plates are spaced apart from each other by a gap of the order of 0.025 metres. In the case where a single baffle plate is provided, the baffle plate has a gap of the order of 0.025 metres located centrally in the baffle plate.

In another embodiment of the invention there is provided a refrigerated food storage unit in which the baffle plate is located a distance from the fan of the order of between 60% and 70% of the total distance between the fan and the cooling unit.

In a further embodiment of the invention there is provided a refrigerated food storage unit in which there are provided a plurality of circular shaped apertures formed in the baffle plate. Alternatively, there are provided a plurality of obround shaped apertures formed in the baffle plate. There may be a combination of circular shaped apertures and elongate obround shaped apertures formed in the baffle plate.

In one embodiment of the invention there is provided a refrigerated food storage unit in which the chilling coil is mounted in the air circulation duct spaced apart from and raised above the floor of the air circulation duct.

In another embodiment of the invention there is provided a refrigeration food storage unit in which there is provided a projecting lip located above and projecting outwardly from the air discharge outlet. Ideally, the projecting lip is downwardly depending.

Detailed Description of the Invention

The invention will be more clearly understood from the following description of some embodiments thereof, given by way of example only with reference to the accompanying drawings, in which: Fig. 1 is a cross-sectional view of a refrigerated food storage unit according to the present invention; Fig. 2 is a front view of a refrigerated food storage unit from above with the compartment floor of the food storage compartment removed showing the cooling coil; Fig. 3 is a perspective view of the front and rear vents along with the baffle plate; Fig. 4 is a perspective view of the front vent; Fig. 5 is a perspective view of the rear vent; Fig. 6 is a perspective view of the baffle plate; Fig. 7 is a perspective view of a second embodiment of baffle plate according to the present invention; Fig. 8 is a perspective view of a third embodiment of baffle plate according to the present invention; Fig. 9 is a perspective view of a fourth embodiment of baffle plate according to the present invention; and Fig. 10 is a perspective view of a second embodiment of front vent according to the present invention.

Referring to Fig. I of the drawings, there is shown a cross-sectional view of a refrigerated food storage unit, indicated generally by the reference numeral 1 comprising a cabinet 3 having a food storage compartment 5, a refrigeration compartment 7 and a transparent display shield 9 covering the food storage compartment and an opening 11 in the display shield adjacent the rear of the cabinet to allow access to the food storage compartment. The food storage compartment comprises a compartment floor 13 suitable for reception of food in containers 15.

The refrigeration compartment 7 comprises a chilling unit 17, a fan unit 19 and a air circulation duct 21. The air circulation duct 21 comprises an air charging inlet 23 located adjacent the front 25 of the cabinet 3 and in fluid communication with both the air circulation duct 21 and the food storage compartment 5. The air circulating duct further comprises an air discharge outlet 27 located adjacent the rear 29 of the cabinet and in fluid communication with both the air circulation duct and the food storage compartment 5. The fan unit 19 comprises a tangential fan mounted in the air circulation duct 21 adjacent to the air charging inlet 23. The chilling unit 17 comprises a cooling coil mounted in the air circulation duct 21 adjacent to the air discharge outlet 27. The refrigeration compartment 7 further comprises a baffle plate 31 mounted in the air circulation duct 21 intermediate and spaced-apart from the fan 19 and the chilling unit 17. The baffle plate 31 comprises a plurality of spaced-apart apertures therein (not shown) for through-passage of air.

In use, the fan 19 is operable to circulate air in the cabinet 3 by drawing air into the air circulation duct 21 of the refrigeration compartment 7 from the food storage compartment 5 through the air charging inlet 23. The fan unit 19 drives the air along the air circulation duct 21 through the baffle plate 31. The baffle plate 31 disperses the concentrated flow of air from the fan across the entire width of the air circulation duct 21 downstream of the baffle plate and prior to the air coming into contact with the cooling coil 17, thereby distributing all of the air from the fan evenly across the cooling coil 17. As the fan is in continuous operation, the air is forced up through the cooling coil 17 and out of the refrigeration compartment 7 to the food storage compartment 5 through the air discharge outlet 27. The chilled air passes over the food in the containers 15 until it is recirculated by being drawn in to the air charging inlet 23 once again. The direction of flow of air through the cabinet is shown by arrows 32.

Referring to Fig. 2 of the drawings, there is shown a front view of the cabinet from above with the compartment floor of the food storage compartment 5 removed and the cooling coil 17 exposed. The cooling coil of the chilling unit 17 is mounted in the air circulation duct 21 adjacent to the air discharge outlet (not shown). The cooling coil 17 has a plurality of substantially parallel, overlapping, vertically arranged fins 33 mounted side by side and extending substantially across the entire width of the cabinet 3. An evenly distributed air flow as indicated by arrows 32 is shown approaching the fins 33 of the chilling unit 17. The air, passes up between the fins 33 of the coil and is cooled as it passes the fins 33.

Referring to Figs. 3 to 6 inclusive, there is shown a plurality of perspective views of various parts of the refrigerated food storage unit 1. Referring first of all to Fig. 3, there is shown a perspective view of the baffle plate 31, a front vent 35 which forms the air charging inlet 23 and a rear vent 37 which forms the air discharge outlet 27. It can be seen that the air charging inlet 23 comprises a plurality of elongate obround apertures formed along the length of the front vent 35. Furthermore, it can be seen that the air discharge outlet 27 comprises a plurality of obround apertures disposed along the length of the rear vent 37. The baffle plate 31 is provided with a plurality of spaced-apart apertures 39 therein for through-passage of air. The spaced-apart apertures 39 are arranged about the baffle plate to disperse the concentrated flow of air from the fan across the entire width of the air circulation duct downstream of the baffle plate 31 and prior to the air coming into contact with the cooling coil (not shown). The baffle plate 31 in fact comprises a pair of baffle plates 31a, 31b separated by a gap 41 of the order of 0.025 metres.

The air flow between the front vent 35, baffle plate 31 and rear vent 37 is shown diagrammatically with arrows. The size of the arrows is representative of the concentration of the air flow in a particular area, It can be seen from Fig. 3 that there are two main areas of concentration of air flow 43, 45 coming from the front vent 35.

In this case, there is in fact a pair of tangential fans (not shown) and the air flow streams 43, 45 each emanate from one of the tangential fans. The concentrated stream of air 43, 45 comes into contact with the baffle plate 31(a), 31(b) respectively and the concentrated air flow 43, 45 are dispersed by the baffle plates 31(a), 31(b).

The air flow is dispersed evenly across the entire width of the air circulation duct 21 downstream of the baffle plates 31(a) and 31(b) prior to the air flow coming into contact with the cooling coil (not shown). The evenly dispensed air flow is illustrated by arrows 47. The air flow 47 is evenly distributed across the width of the air circulation duct 21 and the air flow 47 is directed towards a cooling coil (not shown) which extends across the width of the refrigerated food storage unit, thereby distributing all of the air flow from the fan unit evenly across the cooling coil. By doing so, the air flow will flow up through the cooling coil between the fins and will be cooled at an even rate and will be discharged from the air discharge outlet 27 from the rear vent 37.

Referring specifically to Fig. 5, the rear vent 37 comprises an outwardly and downwardly depending lip 49 mounted above the air discharge outlet 27. The lip 49 causes the outgoing chilled airflow to be directed downwardly towards the food (not shown).

Referring specifically to Fig. 6 of the drawings, there is shown an enlarged view of the middle baffle plate 31, comprising a pair of baffle plates 31(a), 31(b). Each baffle plate 31(a), 31(b) can be divided into a number of zones 51, 53. In zones 51, there is provided a plurality of circular apertures 55 evenly spaced in the zone 51. In zones 53, there is a plurality of elongate obround shaped apertures 57 substantially parallel with respect to each other. These zones 51, 53 are arranged so that the incoming airflow (not shown) is dispersed evenly across the entire width of the baffle plate 31(a), 31(b). Thereby evenly dispersing the incoming airflow across the entire width of the cabinet. This is achieved by varying the amount of air that is allowed flow through zones 51, 53 by altering the size, shape and/or number of the apertures. The less apertures in a zone, the less air will flow through that zone. In this way, the flow of air through the baffle plate can be controlled.

Referring to Fig. 7 of the drawings, there is shown an alternative construction of baffle plate indicated generally by the reference numeral 71, where like parts have been given the same reference numerals as before. The baffle plate 71 in fact comprises a pair of baffle plates 71(a), 71(b) separated by a gap 41. Each baffle plate 71(a), 71(b) is divided into a plurality of zones 51, 53. In this embodiment, instead of elongate obround shaped apertures in zones 53, the baffle plate 71 is provided with a plurality of circular holes 73 in the zones 53. However, there are fewer holes 73 in the zones 53 than there are holes 55 in zones 51. In the embodiment shown, the holes 73 are of the same diameter as the holes 55.

Referring to Fig. 8 there is shown an alternative embodiment of baffle plate, indicated generally by the reference numeral 81, where like parts have been given the same reference numerals as before. The baffle plate 81 in fact comprises a pair of baffle plates 81(a), 81(b) each having a plurality of zones 51, 53 along the length thereof.

The baffle plates 81(a) and 81(b) are separated by a gap 41. The baffle plates 81(a) and 81(b) have the same number of apertures in zones 53 as there are in zones 51, however the apertures 83 in zones 53 are of different diameter, in this case smaller, than the diameter of the apertures 55 in zones 51. This will have the affect of altering the airflow incident on the baffle plate and dispersing the airflow so that it is evenly distributed across the width of the baffle plate 81(a), 81(b).

Referring to Fig. 9 of the drawings, there is shown an alternative construction of baffle plate indicated generally by the reference numeral 91, where like parts have been given the same reference numerals as before. The baffle plate 91 comprises a pair of baffle plates 91(a), 91(b) separated by a gap 41. Each baffle plate 91(a), 91(b) is divided into a plurality of zones 51, 53, each having a plurality of apertures therein. The apertures 55 in the zone 51 are similar in dimensions to the apertures 93 in zones 53, however there are fewer apertures 93 in zones 53 than there are apertures 55 in zones 51. In this respect, this is similar to the embodiment shown in Fig. 7. The baffle plates 91(a), 91(b) are arcuate in shape and have a distance, D, between the free ends of the plates of approximately 0.5m (500mm). The baffle plates 91(a), 91(b) have a maximum depth of curvature, C, of the order of 0.lm (100mm). The baffle plates 91(a), 91(b) are spaced apart from each other by a gap of the order of 0.025m (25mm). The arcuate shaped baffle plates 91(a), 91(b) have been found to be particularly effective at dispersing incoming airflows 43, 45 shown diagrammatically by arrows 43, 45, into an even airflow distributed across the width of the air circulation duct.

In the embodiments shown, the baffle plates 31, 71, 81, 91 have been shown as two-part baffle plates. This is due to the fact that there are typically provided a pair of tangential fans in the refrigerated food storage unit. However, it will be understood that units having a single tangential fan, or indeed more than one tangential fan may be provided depending on the width of the refrigerated food storage unit. It is envisaged that there would be provided a baffle plate for each tangential fan located in the refrigerated food storage unit. However, a single continuous baffle plate that extends across the entire width of the cabinet 3 could also be provided, It is envisaged that instead of providing a plurality of plates with a gap therebetween, a single plate with a cut-out to provide an air passageway though the baffle plate could be provided in its stead. The single plate would have the cut-out stamped out of the body section. The single plate could be bent into an arched configuration similar to that shown in Figure 9 or could simply be provided in a single continuous arc across the entire width of the cabinet.

Furthermore, in the embodiments shown, both circular and obround race-track shaped apertures are provided. It is envisaged that other shaped apertures could be provided such as square, rectangular, pentagonal or hexagonally shaped apertures and a combination of various different shapes of apertures could be provided on the one baffle plate.

Referring to Figure 10 of the drawings, there is shown an alternative embodiment of front vent, indicated generally by the reference numeral 101, where like parts have been given the same reference numeral as before. The front vent 101 has a pair of air inlet zones 103, 105 adjacent either end of the front vent and a central air inlet zone 107 adjacent the centre of the front vent 101. There are further provided a pair of sealed zones 109, 111, one of which is located intermediate one of the pair of air inlet zones 103 and the central air inlet zone 107 and the other of which is intermediate the other of the pair of air inlet zones 105 and the central air inlet zone 107. The apertures in the central air inlet zone 107 are smaller than the apertures in the other air inlet zones 103, 105.

In this way, as air is delivered across the food, it will not be drawn towards the air inlet directly over the tangential fan but rather will be drawn in adjacent the sides of the cabinet and into the centre of the cabinet. This further spreads the flow if air across the food in the food storage compartment. It is envisaged that holes could be provided in the sealed sections 109 and 111 which are directly above the tangential fans (not shown) however it is envisaged that the holes in the sealed sections 109, Ill would be smaller and/or fewer in number than the holes in the air inlet zones 103, 105. Furthermore, the holes in the sealed zone 109, 111 would be smaller and/or fewer in number than the holes in the central air inlet zone 107.

The position of the baffle plate 31, 71, 81, 91 relative the fan unit 19 and the chilling coil 17 in particular is of significant importance. As can be seen in Fig. 1, the baffle plate 31 is located approximately two thirds of the depth of the unit from the front 25 of the cabinet 3. Preferably, the baffle plate 31 is located a distance from the fan of the order of 60% and 70% of the total distance between the fan and the cooling unit.

Ideally, the baffle plate is located a distance from the fan of the order of 67% of the total distance between the fan and the cooling unit. In this way, the concentrated streams of airflow emanating from the fan will be allowed to partially disperse before impacting on the baffle plate 31 and the baffle plate 31 will be able to further disperse the airflow evenly across the entire width of the cabinet 3 prior to the airflow coming into contact with the cooling coil 17. This ensures that there is an evenly distributed airflow across the coil 17 and the efficiency of the cooling effect of the coil on the air is maximised by the air spending the maximum amount of time in contact with the cooling coil fins before being discharged through the air discharge outlet 27. The result is a more evenly cooled airflow distributed across the food in the food storage compartment.

Testing of the refrigerated food storage unit according to the present invention has shown a significant reduction in incidences of hot and cold spots in the cabinet.

Furthermore, the maximum deviation from the desired temperature has been found to be � 2°C which represents approximately a 60% reduction in the deviation from the desired temperature of the known units. This obviates the possibility of foodstuffs spoiling prematurely, removes the health and safety risk and provides an improved refrigerated storage unit.

In the specification the terms "comprise, comprises, comprised and comprising" or any variation thereof and the terms "include, includes, included and including" or any variation thereof are considered to be totally interchangeable and they should all be afforded the widest possible interpretation and vice versa.

The invention is in no way limited to the embodiments hereinbefore described but may be varied in both construction and detail with the scope of the claims.

Claims

Claims 1) A refrigerated food storage unit comprising: a cabinet having a food storage compartment, a refrigeration compartment, a transparent display shield covering the food storage compartment and an opening in the display shield adjacent the rear of the cabinet to allow access to the food storage compartment; the food storage compartment comprising a compartment floor suitable for reception of food in containers; the refrigeration compartment comprising a chilling unit, a fan unit and an air circulation duct; the air circulation duct comprising an air charging inlet located adjacent the front of the cabinet and in fluid communication with both the air circulation duct and the food storage compartment, and an air discharge outlet located adjacent the rear of the cabinet and in fluid communication with both the air circulation duct and the food storage compartment; the fan unit comprising a tangential fan mounted in the air circulation duct adjacent to the air charging inlet, the fan being operable to circulate air in the cabinet by drawing air into the air circulation duct of the refrigeration compartment from the food storage compartment through the air charging inlet, driving the air along the air circulation duct, and forcing the air back out of the refrigeration compartment to the food storage compartment through the air discharge outlet; the chilling unit comprising a cooling coil mounted in the air circulation duct adjacent to the air discharge outlet, the cooling coil having a plurality of substantially parallel, overlapping, vertically arranged fins mounted side by side and extending substantially across the entire width of the cabinet; the refrigeration compartment further comprising a baffle plate mounted in the air circulation duct intermediate and spaced apart from the fan and the chilling unit; the baffle plate comprising a plurality of spaced apart apertures therein for through passage of air, the spaced apart apertures being arranged about the baffle plate to disperse the concentrated flow of air from the fan across the entire width of the air circulation duct downstream of the baffle plate and prior to the air coming into contact with the cooling coil thereby distributing all of the air from the fan evenly across the cooling coil.
2) A refrigerated food storage unit as claimed in claim I in which the baffle plate is arcuate in shape.
3) A refrigerated food storage unit as claimed in claim 2 in which the baffle plate has a depth of curvature of the order of 20% of the length of the baffle plate.
4) A refrigerated food storage unit as claimed in any preceding claim in which there is provided a gap of the order of 0.025 metres located centrally in the baffle plate.
5) A refrigerated food storage unit as claimed in any preceding claim in which the baffle plate is located a distance from the fan of the order of between 60% and 70% of the total distance between the fan and the cooling unit.
6) A refrigerated food storage unit as claimed in any preceding claim in which the plurality of apertures are uniform in size and the number of apertures in an area of the baffle plate is chosen to regulate flow of air through the baffle plate in that area.
7) A refrigerated food storage unit as claimed in any of claims 1 to 5 in which there are provided a plurality of apertures of different sizes with respect to each other and the size of the apertures in an area of the baffle plate are chosen to regulate flow of air through the baffle plate in that area.
8) A refrigerated food storage unit as claimed in any preceding claim in which the baffle plate has a depth of curvature of the order of 0.1 metres and a length from end to end of the order of 0.5 metres.
9) A refrigerated food storage unit as claimed in any preceding claim in which there is provided a pair of baffle plates mounted side by side in the air circulation duct and spaced apart from each other.
10) A refrigerated food storage unit as claimed in claim 9 in which the pair of baffle plates are spaced apart from each other by a gap of the order of 0.025 metres.
11) A refrigerated food storage unit as claimed in any preceding claim in which there are provided a plurality of circular shaped apertures formed in the baffle plate.
12) A refrigerated food storage unit as claimed in any preceding claim in which there are provided a plurality of obround shaped apertures formed in the baffle plate.
13) A refrigerated food storage unit as claimed in any preceding claim in which the chilling coil is mounted in the air circulation duct spaced apart from and raised above the floor of the air circulation duct.
14) A refrigerated food storage unit substantially as hereinbefore described with reference to and as illustrated by the accompanying drawings.