The present invention relates to an air refrigeration unit.
Among the various types of air refrigeration unit currently commercially available, one is substantially constituted by a cabinet, composed of a frame and of covering panels, in which an evaporator is conveniently arranged between the other refrigeration devices and a series of two fans.
A duct is defined in the cabinet, which contains the evaporator and the fans and is suitable for conveying air from a room and for returning it thereto after treating it.
A seperate duct suitable for drawing external replacement air is also currently defined in said duct so as to terminate upstream of the evaporator.
However, since the outlet of said seperate duct is arranged upstream of the evaporator, i.e. in a region where the suction effect of the series of fans is scarcely felt, and since said evaporator constitutes an element which induces a high load loss on the air flow as passes through it,the drawn replacement air flow-rate is extremely low and thus insufficient.
In order to solve this problem, an additional fan has been arranged in the seperate duct, but this obviously entails an increase in cost for the entire apparatus.
The aim of the present invention is to provide an air refrigeration unit which solves the problem described above in known types.
A consequent primary object is to avoid resorting to an auxiliary fan for the external replacement air.
Another object is to provide a refrigeration unit which is not more complicated than current units.
Not least object is to provide an air refrigeration unit which can be used with conventional machines and facilities.
This aim, these objects and others which will become apparent hereinafter are achieved by an air refrigeration unit of the type which comprises: a box-like body composed of a supporting frame and covering panels; a refrigeration circuit comprising an evaporator; a battery of fans; a duct defined in the box-like body for conveying ambient air to and from the space to be conditioned; whereby the evaporator is arranged at a median position between the battery of fans and the other devices of the refrigeration circuit, and; whereby the evaporator and the battery of fans are arranged in the duct for conveying ambient air, said unit being characterized in that a further seperate duct is defined in the unit which connects the region downstream of the evaporator to an opening for drawing outside replacement air.
Further characteristics and advantages of the invention will become apparent from the detailed description of an embodiment thereof, illustrated only by way of non-limitative example in the accompanying drawings, wherein:
With reference to the above figures, the air refrigeration unit according to the invention comprises a frame 1 made of metallic elements defining a parallelepipedal box-like body 2 which is conveniently closed by covering panels, which are not illustrated.
The various air treatment elements are arranged in said body 2.
In particular, an evaporator 3 is arranged transversely and in an inclined position in a median region inside a duct 4 defined in said structure. The intake opening 5 of the evaporator 3 is arranged in a median lateral region in a position directly underlying an operation and control panel 6.
Said duct 4, which is substantially L-shaped, ends above the evaporator 3 in the region wherein a battery of two fans 7 is arranged, the delivery outlets 8 of said fans being directed upward and thus being suitable for returning the treated air into the room.
The other refrigeration devices, generally indicated by the reference numeral 10, are arranged below said evaporator 3 and are divided therefrom by means of a wall 9 which delimits the duct 4.
According to the invention, a seperate duct 12, having a substantially rectangular cross-section and arranged vertically, is defined on the side opposite to said intake opening 5 in the unit between the walls 11 of the channel system 4 and the covering panels.
Said seperate duct 12 is connected, in a downward position, by means of a flexible connecting hose 13, to an opening 14 which is defined in the bottom in the region of the devices 10 and is adapted for drawing outside replacement air.
In an upward position, said seperate duct 12 has a lateral hole at which a cylindrical filter 15 is arranged; said filter connects said seperate duct to the region downstream of the evaporator 3 immediately upstream of the axial suction inlet of one of the fans 7.
The fact that the outlet of the seperate duct 12 is in the region downstream of the evaporator 3, i.e. in a region wherein the air suction produced by the fans 7 is felt considerably, causes an amount of replacement air sufficient to provide a sufficient replacement in the room to be drawn through said outlet.
With this arrangement of the seperate duct 12 it is therefore no longer necessary to use an additional fan as provided in current types.
In practice it has thus been observed that the air refrigeration unit according to the invention has achieved the intended aim and objects, the disadvantages observed in known types having been eliminated by defining in said unit a particular duct suitable for drawing replacement air.
The air refrigeration unit can be manufactured without particular problems by modifying the current structures and is more economical than known types by virtue of the fact that it does not have the additional fan.
In practice, the materials employed, so long as they are compatible with the contingent use, and the dimensions may be any according to the requirements.