AU720769B2 - An improved refrigerated cabinet - Google Patents

Description

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT Name of Applicant: Actual Inventor: Address for Service: Invention Title: ORFORD PTY LTD JOHN HENRY ORFORD CULLEN CO., Patent Trade Mark Attorneys, 240 Queen Street, Brisbane, Qld. 4000, Australia.

AN IMPROVED REFRIGERATED

CABINET

Details of Associated Provisional Application: No. PO5142 filed 18 February 1997 The following statement is a full description of this invention, including the best method of performing it known to

US:

THIS INVENTION relates to an improved refrigerated cabinet. In particular, the invention is directed to a refrigerated display cabinet having means for the reduction or prevention of the formation of condensation on the doors thereof.

BACKGROUND ART Refrigerated cabinets with glass doors are commonly used for displaying refrigerated merchandise in shops. As the glass doors are cooled by the cold air within the cabinet to below the dewpoint of the ambient air, condensation will tend to form on the outside of the glass doors. This condensation not only detracts from the appearance of the display cabinet but also accelerates corrosion of metal fittings on the doors and the cabinet.

Furthermore, as the merchandise within the cabinet is obscured by condensation forming on the glass doors, customers will tend to open the doors more often to view the merchandise, thereby increasing the running costs of the refrigerated cabinet.

The establishment of a flow of warm air over the glass doors is a well known method of removing condensation. Examples of refrigerated cabinets having condensation removing air flow can be found in United States Patents Nos. 3,462,966; 4,009,586; 2,706,387; 3,307,373; 3,025,681 and 2,673,455. Most of the known devices use a fan to blow air from a refrigerating :mechanism on the bottom of the cabinet, upwardly over the door of the refrigerated cabinet. The air is warmed as it 30 passes through the condenser of the refrigerating mechanism, and the warmed air is diverted up the door to minimise and/or prevent the formation of condensation on the door.

There is an increased demand for refrigerated cabinets in which the refrigerating mechanism is situated above the refrigerated space and the door(s) (commonly ooo o known as "top-mounted" refrigerated cabinets). The refrigeration mechanism is typically located behind a display sign above the door(s).

The condenser fan of a conventional top-mounted refrigerated cabinet draws air from the open top of the refrigerating unit. The air is warmed as it passes through the condenser after which it is exhausted from the top of the refrigerating cabinet. The exhausted air is at a higher temperature than the ambient air and may be drawn back into the refrigeration mechanism. This causes the heat exchanger to operate at a higher temperature than necessary and reduces the efficiency of the refrigeration mechanism. This problem is increased where there is little clearance between the top of the refrigeration unit and the ceiling.

As known top-mounted refrigerated cabinets circulate air above the refrigerating unit, there is little air circulation over the doors. Other means are therefore used to minimise or prevent the formation of condensation on the doors, such as electrically heated doors. However, the provision of electrically heated doors on a refrigerated cabinet increases the cost of the cabinet and its running cost, and is therefore undesirable.

It is an object of the present invention to overcome, or at least substantially ameliorate, one or 25 more of the foregoing disadvantages of the prior art by providing an improved top-mounted refrigerated cabinet having means for reducing the formation of condensation thereon on the cabinet doors.

It is another object of the present invention to provide a refrigerated cabinet having an improved air flow to reduce the condensing temperature.

SUMMARY OF THE INVENTION In one broad form, the present invention provides a refrigerated cabinet having at least one upright door; refrigerating means, including a condenser, located at the top of the cabinet; vent means located adjacent the top of the door(s); and means for creating air flow through the vent means to thereby induce movement of air over the door(s).

In a preferred embodiment, the vent means includes a plurality of air vents opening downwardly towards the door(s). The vent means may also comprise a plurality of air vents opening outwardly from the cabinet.

The means for inducing airflow through the vent means is suitably a fan associated with the refrigerating means.

Typically, the refrigerated cabinet includes a display panel situated above the door(s) in front of the refrigerating means. A space is provided behind and below the display panel, to allow air to flow between the refrigerating means and the vent means which is situated between the display panel and the door(s).

In use, air flow is created through the condenser of the refrigerating means, the space behind and below the display panel and the vent means. The flow of air through the vent means results in movement of air over the doors. This movement of air reduces or prevents the formation of condensation on the outer surface of the doors.

The air may be drawn from in front of the c. cabinet, into the vent means, and through the 25 refrigerating means from where it is exhausted to the back and/or top of the refrigerated cabinet.

Alternatively, the air may be drawn from the back and/or top of the refrigerated cabinet, through the refrigerating means and directed out through the vent 30 means.

The flow of air in either direction through the vent means induces or produces movement of air across the S"door(s).

The refrigerated cabinet may include air ducting to direct air between the top and bottom of the cabinet.

The ducting typically includes upper, rear and lower panels which generally form an air duct from the refrigerating means to a lower vent at the bottom of the door(s). The lower vent preferably includes a plurality of apertures opening upwardly towards the door(s). The lower vent may also include a plurality of apertures opening outwardly from the cabinet.

The duct forms a flow path from near the display panel at the top of the refrigerated cabinet to the lower vent situated below the door(s). The air is generally constrained to flow through the duct. Air may be drawn in through the upper vent and the refrigerating means (where it is warmed) and channelled down the rear of the cabinet and under the cabinet to exit from the lower vent. The air then flows upwardly over the doors. Alternatively, the air flow may be reversed so that the movement of air over the doors is generally downward.

Such ducting increases the amount of air flowing across the door(s), and therefore increases the amount of condensation that can be removed from the door(s) due to the action of both vents. Further, the ducting allows the refrigerated cabinet to be built into a wall or be used in various situations where the space between the cabinet and the ceiling and/or wall is limited.

In order that the invention may be more fully understood and put into practice, a preferred embodiment thereof will now be described with reference to the 25 accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a schematic sectional side elevation of a refrigerated cabinet in accordance with a first 30 embodiment of the present invention; Figure 2 is a schematic sectional side elevation of the upper part of the refrigerated cabinet of Figure 1; Figure 3 is a schematic sectional side elevation

S

of the refrigerated cabinet of Figure 1; Figure 4 is a perspective view of the vent means shown in Figures 1, 2 and 3; 55.5o5 Figure 5 is a schematic sectional side elevation of a second embodiment of the refrigerated cabinet of the present invention; and Figure 6 is a sectional side elevational of the refrigerated cabinet of Figure DESCRIPTION OF PREFERRED EMBODIMENT As shown in Figures 1 to 4, a refrigerated cabinet 10 of a first embodiment of this invention houses a refrigerated space 14. A refrigerating mechanism 12 (known in the art and shown schematically as a blank box) is situated above the refrigerated space 14, and is adapted to cool the refrigerated space 14. The refrigerating mechanism 12 includes a fan 18 for moving air through a condenser 34 of the refrigerating mechanism 12.

The refrigerated space 14 is closed by a door 16 which is typically made of glass, thus allowing the contents of the refrigerated space 14 to be viewed from the outside without opening the door 16. A display panel is mounted above the door 16 for advertising purposes, and hides the refrigerating mechanism 12 from view.

In the illustrated embodiment, the condenser 34 is located at the front of the refrigeration mechanism and '"the fan 18 is mounted on the inside of the condenser. A space 21 is provided between the display panel 20 and the condenser at the front of the refrigerating mechanism 12.

A vent fitting 22 is located between the display 20 and the door 16, and preferably extends forward of the door 16. As shown more clearly in Fig. 4, the vent fitting 22 includes apertures 24 located on a forward face 28 of the air inlet 22, and apertures 26 located on a lower face S- These apertures communicate with the space 21 at the front of the condenser 34.

The vent fitting 22 also includes a number of end portions 32 which may be used to attach the fitting 22 oeooo 35 to the housing In use, the fan 18 draws air through the vent fitting 22, the space 21 and the condenser 34 (where it is warmed). The air is then exhausted by the fan 18 from the upper and rear portions of the refrigerated cabinet 10, as shown in Figures 1 and 2.

Alternatively, the flow of air may be in the reverse direction as shown in Figure 3. Namely, air is drawn from the upper and rear portions of the refrigerated cabinet 10 and is blown through the condenser of the refrigerating mechanism 12 by the fan 18. The warmed air passes through the space 21 between the refrigerating mechanism 12 and the display 20, and is exhausted through the vent fitting 22.

In either case, the flow of air through the vent fitting 22 induces movement of air over the door 16. The apertures 26 located on the lower face 30 of the vent fitting 22 are preferably arranged to extend at least as wide as the door 16, so that the induced current of air flows across the whole width of the door 16.

Figures 5 and 6 illustrate a cabinet having additional air ducting 40. The ducting 40 is suitably formed by a cabinet top cover 42, and sheeting 44 spaced from the back and bottom of the refrigerated space 14.

In use, the fan 18 draws air through the vent fitting 22, the space 21 and condenser 34 as shown in Figure 1. The air is then exhausted to the rear of the :'.refrigerating mechanism 12. As the cabinet cover 42 25 effectively seals the top of the refrigerated cabinet the air is constrained to flow through the ducting 40 at the rear and underside of the refrigerated cabinet 10. A vent fitting 46, which may be similar to vent fitting 22 shown in Figure 3, is located adjacent and below the doors 16. The vent fitting 46 is provided with apertures at its .top. The air is expelled through the apertures upwardly along the surface of the door 16 as shown in Figure Alternatively, the induced air flow may be in the reverse direction, as shown in Figure 6. Namely the 35 fan 18 draws air from the rear of the refrigerating mechanism 12 and blows the air through the condenser 34 into the space 21 and out through vent fitting 22. The fan draws air through the lower vent fitting 46 and along the channelling 40 under and behind the refrigerated cabinet The air flow from the vent fitting 22 and air flow into vent fitting 46 induce a current of air flowing down the door 16.

It should be noted that although air flows between the vent fitting 22 and vent fitting 46, the amount of air that is recirculated is only a small portion of the total air in the system and therefore does not affect the performance of the refrigerating mechanism 12.

Further, the air is cooled as it flows across door 16.

The ducting 40, including top cover 42, sheeting 44 and vent fitting 46, may all be fittings, either separate or integrated, which can be retrofitted to the first embodiment.

In the top-mounted refrigerated cabinet of this invention, the condenser fan induces movement of air over the outer face of the door 16. The current of air along the outer face of the door 16 minimises and/or prevents the formation of condensation on the door and also helps to remove any condensation present. Even a small amount of air movement over the door is effective in reducing condensation. By this arrangement, it is no longer **necessary to heat the air supplied to the outer surface of the door 16, nor to electrically heat the door 16.

S" 25 Further, the present invention alleviates the need to provide a fan at the bottom of the door 16 to supply a current of air to the outer surface of the door 16, as in the prior art.

Another advantage of the described arrangement is that the amount of exhausted air which is recirculated into the cabinet is reduced. The reduction of recirculated (warmed) air results in the air passing through the condenser being at a cooler temperature, increasing heat exchange efficiency and reducing stress on the 35 refrigerating mechanism.

The embodiments of Figs. 5 an 6 are also advantageous where there is restricted clearance above and/or behind the refrigerated cabinet.

The foregoing describes only some embodiments of the invention, and modifications which are obvious to those skilled in the art may be made thereto without departing from the scope of the invention as defined in the following claims.

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Claims (13)

1. A refrigerated cabinet having at least one upright door; refrigerating means, including a condenser, located at the top of the cabinet; first vent means located adjacent the top of the door(s), and means for creating air flow through the vent means to thereby induce movement of air over the door(s).

2. A refrigerated cabinet as claimed in claim 1, wherein the first vent means includes a plurality of air vents opening downwardly towards the door(s).

3. A refrigerated cabinet as claimed in claim 1 or 2, wherein the first vent means includes a plurality of air vents opening outwardly of the cabinet.

4. A refrigerated cabinet as claimed in any preceding claim, wherein the means for creating air flow is a fan adapted to draw or blow air through the condenser.

5. A refrigerated cabinet as claimed in claim 4, wherein, in use, the fan draws air from in front of the cabinet door(s), through the first vent means, and through the condenser, from where it is exhausted to the back and/or top of the refrigerated cabinet.

6. A refrigerated cabinet as claimed in claim 4, wherein in use, the fan draws air in from the back and/or top of the refrigerated cabinet, and blows the air through ."the condenser and out through the first vent means to the front of the door(s).

7. A refrigerated cabinet as claimed in any S* preceding claim, further comprising a display panel located above the door(s), and spaced in front of the condenser to permit air flowing to or from the condenser to pass behind and under the display panel. 35 8. A refrigerated cabinet as claimed in any preceding claim, further comprising second vent means located below the door(s), and ducting at the rear and underside of the refrigerated cabinet to provide an air passage from the condenser to the second vent means.

9. A refrigerated cabinet as claimed in claim 8 when appended to claim 4, wherein in use, the fan blows air through the ducting to the second vent means, the second vent means having a plurality of air vents to direct the air upwardly over the door(s). A refrigerated cabinet as claimed in claim 8 when appended to claim 4, wherein in use, the fan induces a flow of air from in front of the door(s), through the second vent means and the ducting.

11. A refrigerated cabinet having a refrigerated space, at least one glass door providing access to the refrigerated space, a display panel mounted above the door(s) and spaced therefrom, a refrigerating mechanism mounted above the refrigerated space and behind the display panel, the refrigerating mechanism having condensing means spaced behind the display panel to allow air communication between the condensing means and the front of the door(s), the refrigerating mechanism also having a fan associated with the condensing means, and vent member located above the door(s) and 25 having a plurality of apertures directed downwardly and/or outwardly over the door(s), wherein in use, the fan blows or draws air through the condensing means to induce a flow of air in front of the door.

12. A refrigerated cabinet having a refrigerated space, at least one door providing access to the refrigerated space, refrigerating means located above the refrigerated space, the refrigerating means including a condenser in air communication with the front of the doors, and means for creating airflow through the condenser to thereby induce movement of air over the door(s).

13. A refrigerated cabinet as claimed in claim 12, further comprising a display panel mounted above the door(s) and spaced in front of the refrigerating means.

14. A refrigerated cabinet as claimed in claim 13, further comprising a vent member mounted between the display panel and the door(s), the vent member having a plurality of apertures therein directed downwardly and/or outwardly over the door(s).

15. A refrigerated cabinet substantially as hereinbefore described with reference to the drawings. DATED this seventeenth day of February 1998 ORFORD PTY LTD By their Patent Attorneys Cullen Co. 99 *9 *o *oo