NL2002604C2 - Device for generating an air wall with a standing cooling unit. - Google Patents

Description

DEVICE FOR GENERATING A AIR WALL AT ONE

STANDING COOLING FURNITURE

The invention relates to a device for generating an air wall for thermally separating the air in a relatively cold first room, namely the inner space of a cooling unit, cold store or the like, for cooled offering in self-service of pre-packaged cooled food items, of the air in the relatively warm second space, namely the surrounding space of the cooling furniture or the cooling cell, which two spaces are in communication with each other via a frontal opening extending in a substantially vertical main surface with a height of at most 2 m , which device comprises: a primary blow-in slot, which is positioned on a primary blower unit positioned near one side of the frontal opening and which is arranged substantially parallel to the main face of the frontal opening, and which extends substantially over the entire relevant dimension of the frontal opening. generating an at least more or less flat primary airstr uncle, which is at least approximately oriented towards the opposite side of the frontal opening.

Such a device is known from WO-A-2006/115824.

Cooling furniture, for example standing wall cooling furniture, and cooling cells are often equipped with a slightly cooled air curtain, wherein the air is supplied at the top and is extracted at the bottom, so that the temperature in the area of the shelves and the bottom is at a at a certain temperature, for example in the range 0 ° C - 10 ° C.

2002604! 2

Where the aforementioned wall cooling furniture and variants are placed on it, the passer-by feels the cool air. As the length and concentration of this cooled wall furniture increases, in a supermarket or other sales area, people often feel the cold in their own way and members!

This cold is unpleasant in the summer for those who come from a summer outside temperature and negatively influences the buying behavior of customers.

Another drawback is the associated energy loss, which is associated with this. The cause of the energy loss is, among other things, the cold that usually flows away or leaks away on the underside of the air curtain. The air curtain is in fact not resistant to form a barrier against the cold layers built up below.

Another cause of energy loss is the air swirls, caused by passers-by. This also leaks cold away.

A further adverse side effect is formed by the creation of an external induction layer along the air curtain, with slow air flow from top to bottom and where also warmer air is entrained in the air curtain.

It is also often seen that air curtains are locally closed or cut off by merchandise which has ended up on the suction grille of the air curtain. This also causes cold air to be lost, which is usually supplemented by warmer air, which must be cooled again.

There are manufacturers of wall cooling furniture that have already established this induction layer, such as in WO-A-2006/115824.

Other constructors apply a controlled secondary air flow at the top by sucking in the air 35 for this purpose by means of fans.

Still other constructors want to combat the cold loss by passing this above-mentioned secondary air flow on the underside and the rear of the wall cooling unit, in order to then suck in again at the top and feed it back to the secondary air flow. Anyway, a new secondary air flow will be created against this, with even lower airflow, whereby the described construction can then be repeated.

All these solutions are affected with the disadvantage that the cold losses are and remain noticeable, with associated energy loss.

In view of the above, the invention provides a device of the type mentioned in the preamble, which is characterized in that two secondary entrained air streams Ss1 and Ss2 are added to the primary air stream Sp, on either side thereof, which secondary entrained secondary air flows have substantially the same direction as the primary air flow;

Ts1 <Tp <Ts2, in which: - Ts1 = the temperature of the secondary entrained air stream on the inside, - Tp = the temperature of the primary entrained air stream, - Ts2 = the temperature of the secondary entrained air stream on the outside; The velocity of the air in the primary air flow is 2-30 m / s; the width of the primary blower gap is in the range of 5-20 mm, preferably 8-15 mm; and the length of the blower gap in the air flow direction is in the range of about 50-150 mm; all such that no mixing occurs between the primary air stream Sp and the two entrained secondary air streams Ss1 and Ss2.

35 Depending on the circumstances, the frontal opening of the cooling unit should be closed single or multiple by one or more adapted air walls with an airflow, formed by a 4 air distribution box at the top along the length of the furniture, with a narrow outlet slot, with a width in the range of approximately 5 to 30 mm and wherein the air is pushed to the air distribution box by two air guide plates with a length in the flow direction of at least 10 cm. The air has a speed of 2-35 m / s between these two air guide plates. If the air flow from this air wall, for example, moves from top to bottom, it can then be led to an evaporator, in order to subsequently return to the air wall via the air distribution box at the top via the air distribution box, cooled and then inside the insulated walls of the cooling unit. This return of air can also be guided under and behind the furniture, to eventually go to the air wall via the air distribution box 15.

Thus, the air walls can be added to an existing cooled air unit, or the air wall in the refrigerator can be built into the cooling circuit.

In view of the air speed in the air wall, the losses with respect to an air curtain will decrease sharply.

This cooled air wall can also work from bottom to top. This results in a better cold distribution in a standing, cooled wall unit. The cool air in the induction current will be pushed up, unless it is not collected for other purposes.

The invention has a number of important applications, for example: 1) an air distribution box for an air wall, which can be added to an existing cooling furniture.

In addition, the built-in original air curtain will remain in service (see figures 1 to 7); 2) the construction of a standing cooling unit. The air wall is thereby integrated with the cooling furniture. Depending on the construction and the necessity, an air curtain can also be provided here (see figures 8 to 11); 3) the installation of an air distribution box for 5 air wall with cold store with open wall, adjacent to the sales area (see figures 12, 13 and 14).

According to a specific aspect of the invention, the device can have the special feature that the blow-in gap is divided into blow-out channels by partitions extending in the air flow direction. This aspect can in particular be technically significant in the case where use is made of relatively low air speeds.

It is generally noted that the invention is intended for use in connection with cooling furniture or cooling cells. It must therefore be understood that wherever the word "refrigerating furniture" is used, it also includes "refrigerating cell".

The invention will now be explained with reference to the accompanying drawings.

In the drawings: figure 1 shows a vertical section through a known cooling furniture with an air curtain and an entrained secondary air flow; figure 2 shows a section corresponding with figure, to which an air distribution box is added as a device according to the invention; figure 3 shows an auxiliary device according to the invention, intended to be added to an existing cooling furniture; figure 4 shows a vertical section through a device according to the invention that generates two air walls; figure 5 shows a view corresponding with figure 3 of an auxiliary device according to figure 4; figure 6 shows a vertical section through a device that is comparable to the device according to figure 2, but wherein the air streams involved also behave according to the koanda effect.

Figure 7 shows a vertical section of an arrangement that is comparable to that according to figure 4, but wherein the entrained secondary air stream is sucked in and circulated; Figure 8 shows a vertical section through a cooling unit with a device according to the invention in yet another embodiment; figure 9 shows a vertical section through an arrangement according to figure 8, but with a cooled inner circuit and an evaporator and a fan on top; figure 10 shows a vertical section through an arrangement in which the blow-in air gap is situated on the bottom side instead of on the top side and both entrained secondary air flows are used effectively individually; figure 11 shows a vertical section through a variant of the embodiment according to figure 10; Figure 12 shows a partial vertical section, wherein an air distribution box is added to an installed auxiliary device according to figure 3; figure 13 shows a vertical cross-section of an embodiment corresponding to figure 12, wherein a secondary air flow operating in a closed circuit is applied; Fig. 14 is a vertical section, with air flows partially indicated schematically, of a variant with an air wall in a cooling cell, adjacent to a sales area, wherein the air inlet gap is located at the bottom; Fig. 15a is a perspective view, partly in transparent view, of a further embodiment; Figure 15b is a perspective view, partly in transparent view, of yet another embodiment; and figure 16 shows a schematic front view of a cooling furniture with a device according to the invention in accordance with the teachings of figure 15.

Everywhere in the following description of the drawings use has been made, where possible and relevant, of the same reference numerals for the same, or at least functionally corresponding parts.

7

Figure 1 shows a standing wall cooling furniture 22, which is provided with means for generating an air curtain 1, consisting of a more or less flat primary air flow with a small thickness and a high flow rate of 2-30 m / s. Reference numeral 2 denotes an entrained secondary air stream operating on the outside. The air in the entrained secondary air stream 2 is considerably cooled as a result of the low flow velocity of both the air curtain 1 and the entrained stream 2. The cooled air tends to accumulate somewhat in the area indicated by 3 at the front of the furniture 22 near the floor 23. The inner space of the wall cooling furniture 22 comprises a number of shelves designated by the reference numeral 4 for carrying the offer food for sale. Furthermore, the furniture comprises an evaporator 5 and a fan 6 for cooling the flowing air, which circulates in a manner more or less closed in the manner shown in Figure 1. Part of the air in the stream 24 between the insulated rear wall 25 and the inner wall 26 reaches the space in the area of the shelves via openings 27.

Figure 2 shows a standing wall cooling furniture 28, the basic configuration of which corresponds to the structure according to Figure 1. In accordance with the teachings of the invention, however, an air distribution box 29 has been added to the relevant furniture, which is adapted to generate an air wall in the form of a fast 30 (2 - 30 m / s) airflow 30 with a small thickness (initial thickness 5-20 mm), which is located on the outside with respect to the slow air curtain 1.

The air distribution box 29 comprises a fan 31, which extracts the air wall 30 at the bottom via an air channel 8, and blows it out again via a primary blower slit 32, such that a more or less closed circuit is formed. The velocity of the air in this primary air stream 30 is approximately 15 to 20 m / s. The width of the blower gap 32 in the plane of the drawing is in the order of magnitude of 10 - 12 mm. Its length in the direction of flow is in the range of about 50 - 150 mm.

The entrained secondary flow on the outside is indicated by the reference number 2 'to distinguish the entrained air stream 2 according to figure 1, which after all flows substantially slower.

Attention is drawn to the fact that the air duct 8 is bounded by the thermally insulating rear wall 25 and an additional thermally insulating wall 33. As a result, cold losses and hence energy losses are kept as small as possible.

Figure 3 shows the top of the air distribution box 29.

Figure 4 shows the configuration according to Figure 2, but with an extension with an additional forced secondary outer flow 9, which forms part of an additional more or less closed air circuit. As the figure shows, the streams of the air curtain 1, the primary air stream 30, the secondary air stream 9 and the outermost entrained secondary air stream 2 in the area of the opening 34 of the furniture 22 move substantially mutually parallel.

Compared to the configuration according to figure 2, the effective thermal insulation, to be expressed as the heat resistance between the relatively warm outer space and the relatively warm inner space, i.e. in the area of the shelves 4, in the furniture 22, will be even greater in the configuration according to figure 4 which is already better than in the configuration according to figure 2.

Figure 5 shows that the multiple air distribution box 35 comprises not only the fan 31 for the primary air flow 30, but also an additional fan 36 for the outer secondary fan.

Figure 6 shows a configuration in which a cooling unit 37 is also provided with a lighting frieze 9. As the drawing clearly shows, the air curtain 1 leaves its normal linear path as a result of the suction of an induction air flow through the primary air flow 30 according to the teachings of the invention. There is thus a dual effect, namely on the one hand the suction as entrained air flow and on the other hand the koanda effect, whereby the air curtain 1 starts to behave like such an air flow. Since the configuration otherwise corresponds to that according to Figure 2, the description of the remaining components is omitted here.

Figure 7 shows a configuration in which the second entrained air stream 10 is sucked in together with the first entrained air stream 9 and circulated. The amount of air drawn in at the bottom must be discharged through an air outlet 12, so that the balance is guaranteed.

Figure 8 shows a configuration in which the air is cooled by an evaporator 5 placed at the top in the furniture, together with an associated pressure fan 13. Cold air is led down through an adjustable opening 14 for cooling the 4 supported food items.

Figure 9 shows a configuration related to that of Figure 8, but having a cooled inner circuit, comprising an evaporator 38 and a fan 39, both of which are arranged at the top.

Figure 10 shows a configuration with a standing cooled wall cooling furniture, according to which configuration the primary flow in the air wall according to the invention flows from bottom to top. The entrained secondary air stream 16 flowing on the inside also flows up, whereby the possibly "falling" cold air also flows upwards. This air flow then passes through the static evaporator 17. The cooled air coming from the evaporator 17 automatically sinks down and reaches the space with the shelves 4 via the openings 27. In this configuration the pressure fan 13 is shown on the bottom. There is no technical reason for this in itself; it could be placed on top with the same effect.

The entrained secondary air stream 18 located on the outside also moves upwards. At the top, this air can be used to cool the condenser of a cooling group 19 located there. This increases the COP of the installation even further.

Figure 11 shows a configuration that can be considered as a variant of the configuration according to Figure 10. Instead of the static evaporator 17, a ventilated evaporator 5 with a low-pressure fan 6 is used. The closed air circuit has approximately the same shape in this embodiment as in the configuration according to Figure 10.

Figure 12 shows an arrangement in which an air distribution box 29 according to figure 3 substantially connects to the wall 40 of a cooling cell 41, adjacent to a sales space 42.

In this embodiment too, a entrained secondary outer air stream 20 is produced in the manner shown.

Figure 13 shows a variant of the arrangement 25 according to Figure 12, wherein it is diagrammatically indicated that an outer entrained air stream 21 forms part of a closed circuit, comprising a blower unit 43 on the top, a suction unit 44 on the bottom, which suction unit via a diagrammatically shown bypass line 46 with a fan 45 is connected to the blower unit.

Fig. 14 schematically shows a variant with an air wall, which is based on a fast thin primary air flow 30 according to the invention, in the access opening of a cooling cell 41, adjacent to a sales space 42, which flow 30 moves upwards. The arrangement is closely related to that according to figures 10 and 11. This relationship is also reflected in the pattern of the secondary flows 16 and 18 shown.

In the configurations according to the above-discussed embodiment according to the invention, the relevant air streams were transported via elongated air blow-in slits, the length of which roughly corresponded to the relevant dimension of the relevant cooling furniture. Smaller channels could also be used to save energy to bring and remove cold air to the relevant location. This also applies to the air distribution. This could mean that it is sufficient to place units left and right with respect to the furniture. It is also not necessary under all circumstances to provide several layers of insulation in the furniture. Omission of this makes the construction of a piece of furniture simpler and cheaper, albeit probably with a slightly lower return.

Figures 15a and 15b show variants of cooling furniture to which air wall devices according to the invention have been added.

Figure 16 shows a front view of a cooling unit with a device according to the invention, which is provided with shelves 4 for carrying products to be offered for sale.

According to the invention, it is possible to use the air wall singly to thermally separate the relatively warm ambient air from the relatively cold air in the inner space of a cooling furniture or cold store. If the temperature difference over this single air wall is small, there will be a slight heat loss.

In the case where two parallel air walls according to the invention are placed, the heat losses per applied air wall will decrease even further.

If a secondary air flow in the same direction is used for a single air wall or two 12 or more parallel air walls, which is fed by sucked in air, an extremely small heat loss is achieved. Such extensions 5 must be weighed against the necessary power of the pressure fan to be used for each forced air flow.

If one wishes to place an air distribution box for air walls on the top of the wall cooling furniture, the elongated lighting frieze may stand in the way. In that case it is possible to remove the lighting box and position the outlet of the air distribution box there and then to place the lighting box thereon. In that case it is necessary in most cases to ensure that the direction of the air blow-in slit is adjustable, namely such that the primary air flow ends at the bottom edge of the furniture. The intention here is to separate the cooled internal air flow circuit from the air wall.

The advantages of the invention can be summarized as follows: 1) There is a large effective heat resistance at the location of the vertical opening, as a result of which energy losses are greatly limited.

2) The temperature in the interior of the refrigerator can be better maintained within narrow limits.

3) The construction according to the invention is simple, cheap and effective.

4) A cooling unit can suffice with a smaller cooling installation and therefore be cheaper.

5) Existing cooling furniture can be supplemented with a unit according to the invention, as a result of which no replacement of existing and still usable cooling furniture is necessary.

6) It is possible to achieve a higher COP by using air from a entrained, secondary air stream for cooling a condenser.

7) The invention is also applicable to sales from cold stores.

8) The structure according to the invention can also be applied in the case where a lighting frieze is located within the cooled space.

Mentioned literature WO-A-2006/115824 10 2002604 4

Claims (20)

1. Device for generating an air wall for thermally separating the air in a relatively cold first room, namely the inner space of a cooling unit, cooling cell or the like, for the cooled presentation in self-service of pre-packaged cooled food items from the air into the relatively warm second space, namely the surrounding space of the cooling furniture or the cooling cell, which two spaces are in communication with each other via a frontal opening extending in a substantially vertical main surface with a height of at most 2 m, which device comprises : a primary blower gap connecting to a primary blower unit positioned near one side of the frontal opening and positioned substantially parallel to the main face of the frontal opening, which blower extends substantially over the entire relevant dimension of the frontal opening for generating an at least one more or less flat primary air flow, which is at least approximately oriented is to the opposite side of the frontal opening, characterized in that two secondary entrained air streams Ss1 and Ss2 are added to the primary air stream Sp, on either side thereof, which secondary entrained air streams have substantially the same direction as the primary air stream ; Ts1 <Tp <Ts2, where: - Ts1 = the temperature of the secondary entrained airflow on the inside, 30. Tp = the temperature of the primary airflow, 2002604 * - Ts2 = the temperature of the secondary entrained airflow on the outside; the velocity of the air in the primary air flow is 2-30 m / s; The width of the primary blower gap is in the range of 5-20 mm, preferably 8-15 mm; and the length of the blower gap in the air flow direction is in the range of about 50-150 mm; 10 such that no mixing occurs between the primary air stream Sp and the two entrained secondary air streams Ss1 and Ss2. 2. Device as claimed in claim 1, wherein the blow-in gap is divided into blow-out channels by partitions extending in the air flow direction. 3. Device as claimed in claim 1 or 2, comprising a suction unit positioned on the opposite side of the frontal opening with a substantially prismatic suction slit, which extends substantially parallel to the blower slit and has substantially the same length as the primary blower slit, to which extraction gap extraction fan means connect. 4. Device as claimed in claim 3, wherein the primary blow-in slit is connected via a conduit to the extraction slit, in which blower means are arranged, which are both the primary blow-in-blower means and the blow-off-blower means, such that the air wall forms part of a substantially closed circuit. 35 5. Device as claimed in any of the foregoing claims, wherein the primary and the entrained secondary air flows move in the vertical direction. 6. Device as claimed in any of the foregoing claims, wherein at least one of the secondary air flows is an entrained air flow. 7. Device as claimed in claim 3, wherein the extraction gap has such a width and is arranged such that it essentially extracts only the primary air stream Sp. 8. Device as claimed in claim 3, wherein a number of regularly distributed passive control valves for equal, constant airflows are added to the extraction gap, such that at each longitudinal position the same airflow passes, such that the air in the airflow concerned at each longitudinal flow position flows almost along a straight path. 20 Device as claimed in any of the foregoing claims, wherein the position and direction of the blower gap is adjustable. Device as claimed in claim 1, comprising at least two mutually parallel blow-in slots. The device of claim 4, wherein the conduit is thermally insulated. 30 12. Device as claimed in any of the foregoing claims, adapted to be added to a cooling cabinet or to be built into a cold store with an open wall, adjacent to a retail space. 35 The device of claim 12, which device is integrated with a cooling unit. Device as claimed in any of the foregoing claims, wherein a curved air curtain of an existing cooling furniture runs inter alia according to the koanda effect with respect to the primary air flow. 5 Device as claimed in claim 5, wherein the cooling furniture is provided with a static evaporator serving as a cooling element, wherein the internal secondary air flow supplies air to the evaporator. 10 Device as claimed in claim 12, wherein the cooling furniture is provided with an evaporator with a fan, which evaporator with fan is placed on the bottom or the top. 15 17. Device as claimed in claim 9, wherein at least two horizontal air blow gaps are placed on the underside and the air coming from the most outwardly placed air gap is blown outwards at least more or less in the horizontal direction at the horizontal side. 18. Device as claimed in claim 16, wherein the air originating from the outer blowing air gap is supplied to the condenser of a cooling installation for cooling thereof, such that an increased COP is obtained, for example an increase of 3 to 8. 19. Device as claimed in any of the foregoing claims, wherein the resulting external entrained air stream is sucked off at a cooling cell and is returned via fan means to a supply distribution box with blow-out gap, such that the relevant air stream forms part of a substantially closed circuit. 20. Device as claimed in any of the foregoing claims, wherein the air flows are supplied and discharged via at least one air distribution box, which is connected to an associated channel with substantially rectangular cross-sectional shape, such that it is possible to place fan means in one box places on one side on the cooling unit and a cooling unit with a cooling group and an evaporator on the other side, or both can be accommodated in one cabinet that can be placed on top of the cooling unit. 10 ★★★ -k + 2 0 0 2 6 0 4 *