Air curtain device

Abstract: The application relates to an air curtain device comprising a housing (2), plate parts (4,5,6,7) arranged in the housing (2) and defining at least one flow duct leading to an outflow opening in a wall of the housing (2). The plate parts (4,5,6,7) are herein connected to form a rigid profile beam (3) which forms a chassis for the device. The device comprises a number of fan units (10,11,12), wherein the profile beam (3) comprises openings in the plate parts and the fan units (10,11,12) are mounted on the outside against the profile beam (3) at the position of the openings.

Description: The invention relates to an air curtain device of the type which is usually arranged close to, in particular above an opening in a wall and is intended to form an air screen in order to keep atmospheres on either side of the wall separate as far as possible. Such an air curtain device comprises a housing wherein plate parts are arranged which define at least one flow duct leading to an outflow opening in a wall of the housing. Fed to the flow duct, for example by means of fans, is air which comes out of the outflow opening and forms said screen. In known air curtain devices the various components are mounted on the housing (see EP-A-0 611 924). Particularly in the case of more complicated air curtain devices with more flow ducts the access to the different components is difficult, which makes maintenance as well as manufacture difficult. It is moreover difficult to construct the housing sufficiently rigidly. The invention has for its object to provide an air curtain device of the stated type which does not have these drawbacks. With the air curtain device according to the invention this object is achieved with the step of claim 1. The rigid profile beam forms a support core, which supports all components. The housing can hereby be built up from parts which are supported by the profile beam. The housing parts can be removed in simple manner without affecting the structural integrity of the device so that the components can be made easily accessible. The advantage is achieved during manufacture that the device is built up from the profile beam, so that the different assembly operations can be performed without hindrance from surrounding components. The step of claim 2 is preferably applied. The profile beam absorbs all forces of any significance so that the direct transmission to the suspension members results in an efficient construction. A favourable further development is characterized in claim 3. The fan units can in this manner be mounted directly on the profile beam, so that no extra assembly supports or the like are necessary. A favourable embodiment is characterized in claim 4. The inclining plate parts provide together with the vertical plate parts a very torsion rigid construction of the profile beam. Use of the step of claim 5 further increases the torsion rigidity so that relatively light plate material will suffice. The invention is further elucidated in the following description with reference to the annexed figures. Fig. 1 shows a cross section of an embodiment of an air curtain device according to the invention. Fig. 2 shows a partly broken away perspective view of a slightly different embodiment. The air curtain device 1 of fig. 1 comprises a housing 2, in the bottom wall of which is arranged a suction grid 13. Likewise situated in the bottom wall is a grid 16 which is embodied as rectifier and forms a blow-out opening for three air flows 17, 18, 19. A suction grid 15 is likewise formed in the right-hand side wall of the housing 2 in fig. 1. The central core of the device 1 is formed by a profile beam 3 which is constructed from a number of mutually connected plate parts. In the embodiment shown the core 3 comprises two vertical plate parts 4 which are arranged at a mutual distance and form a duct through which air coming from the fan 11 is transported to the grid 16. The profile beam 3 further comprises bent plate parts 5, 6 connected to these vertical plate parts 4. Each plate part 5, 6 forms a plate part extending obliquely downward and upward from halfway along a vertical plate part 4. The plate parts extending obliquely upward are connected at their top edge to a plate 7, which is likewise connected to the top edges of the vertical plate parts 4. The mutually connected plates 4, 5, 6 and 7 form the profile beam 3 which forms the support core of device 1, or forms the chassis thereof. To this profile beam 3 are connected all the components of the device which are supported thereby. Some of the important components of the device 1 are the fans 10, 11 and 12. These fans 10, 11 and 12 are mounted at the position of openings formed in the respective plate parts 5, 6 and 7. The fans thus connect directly onto the ducts formed between the various plate parts. The fan 11 communicates with the above mentioned duct between the vertical plates 4 and generates an air flow which leaves the grid 16 as air flow 18. The fan 10 generates an air flow in the duct between the lower part of plate 5 and the left-hand plate 4 which leaves the grid 16 as air flow 17. In mirror-symmetrical manner the fan 12 generates an air flow which leaves the grid 16 as air flow 19. The manner in which the other components are connected to the support core formed by profile beam 3 are not all shown in detail, but a skilled person in the field can choose from numerous options known to him. The air curtain device shown in fig. 1 is particularly intended for arrangement adjacently of the top of an opening in a wall of a freezer cell. In fig. 1 this wall is herein situated on the left-hand side. Cold air escaping from the freezer cell is drawn in via grid 13 by the fans 10 and 11. The air drawn in by fan 10 is immediately blown out from grid 16 as air flow 17. The air drawn in by fan 11 passes over the heat exchanger 14, wherein this air can be slightly heated. The middle air flow 18 can therefore have a slightly higher temperature than the air flow 17. The fan 12 draws in air via grid 15 from the space in which device 1 is mounted. This air is for example at room temperature. The three air flows 17, 18, 19 form in per se known manner a screen between the freezer cell and the adjoining area at room temperature, which greatly limits the exchange of air between the two spaces and thereby loss of cold air from the freezer cell. Use of the middle air flow 18 with heated, dry air from the freezer cell prevents mist from being created due to mixing of the air from the adjoining area with the cold air from the freezer cell. Above the grid 15 in the front wall of housing 2 is formed a cover 25 in the inside of which electrical and electronic components are mounted for controlling the fans 10-12 and optionally the supply of heat-bearing medium to the heat exchanger 14 or electric power if it is an electric heating element. The device 1 can be suspended on supports which engage on suspension members 27, which are directly connected to the profile beam 3 by means of threaded rods 28. The forces acting on profile beam 3 are thus transmitted directly to the suspension members 27, so that the parts of the housing 2 itself are no longer required to perform any supporting function. As shown, the wall parts of housing 2 are covered with heat insulating material. The air curtain device 30 shown in fig. 2 has in principle a construction corresponding with that of fig. 1. Three adjacent air flows are also generated herein. The profile beam 31 is constructed from a number of plate parts which again define air ducts. The plate parts can be mutually connected by spot welds to form the profile beam 31. Alternatively, the plate parts can be mutually connected by blind rivets. Three rows of fans 32 are arranged in lengthwise direction of device 30, wherein each row provides one of the said conditioned air flows. In order to suspend the device 30 C-profiles 33 are arranged on both sides of the housing, which face upward with a slot-like opening. In a manner not further shown the profiles 33 are directly connected to profile beam 31 so that the forces are transmitted over the shortest possible path to the profiles 33. The device 30 hangs on threaded rods which are fixed to a frame 35 which rests on supports 36 fixed to a wall. The threaded rods engage in the profiles 33 in that a nut screwed onto the threaded rod grips in each case under the mutually facing flanges of the C-profiles 33. Instead of assembly of the electronic and electrical components to the movable cover as shown in fig. 1, in the device 30 these components are arranged on a panel 37 which is accessible behind a cover 38. The panel 37 can be mounted such that this can be pivoted outward through the opening formed when cover 38 is opened, in order to acquire access to the fans 32. Because the profile beam 31 forms the supporting construction which is directly connected to the supports, the wall parts of the housing can be mounted releasably in simple manner so that, when the device requires servicing, these plate parts can be removed rapidly and all essential components of the device become easily and quickly accessible. The invention is also advantageous in the manufacture of the device since assembly of the device from the component parts takes place working from inside to outside, so that for example the housing parts making access to the components difficult are only arranged after all assembly operations have been carried out. These parts therefore cause no problems during assembly. Although the invention is particularly suitable for use in an air curtain device with several air flows, in view of the complexity of such a device and the plurality of components thereof, the invention can also be advantageously applied in single air curtains. The ease with which the housing wall parts can be removed to enable access to the interior of the device is also of essential importance for single air curtain devices in order to limit assembly costs and maintenance costs.

Claims: Air curtain device (1, 30) comprising a housing characterised in that plate parts (4-7) are arranged in the housing (2) and define at least one flow duct leading to an outflow opening (16) in a wall of the housing, wherein the plate parts are connected to form a rigid profile beam (3, 31) which forms a chassis for the device. Device as claimed in claim 1, wherein suspension members (27) for suspending the device engage onto the profile beam (3, 31). Device as claimed in any of the foregoing claims comprising a number of fan units (10-12), wherein the profile beam (3, 31) comprises openings in the plate parts and the fan units are mounted on the outside against the profile beam at the position of the openings. Device as claimed in any of the foregoing claims, wherein the profile beam (3, 31) comprises a central vertical duct bounded by two vertical plate parts (4) and two side ducts which are bounded by plate parts (5, 6) extending obliquely downward from halfway along the vertical plate parts. Device as claimed in claim 4, wherein the profile beam (3, 31) further comprises two plate parts (5, 6) extending obliquely upward from halfway along the vertical plate parts (4) and a plate part (7) connecting the top edges of these plate parts (5, 6) and the top edges of the vertical plate parts (4).

Inventors: LIGTENBERG PETRUS JOSEPHUS J H, LIGTENBERG, PETRUS JOSEPHUS JOANNES HUBERTUS
Applicants: BIDDLE F H BV, F.H. BIDDLE B.V.
Application year: 1995
Main classification: F24F9
IPC codes: F24F9