CLOSING SYSTEM FOR COLD ROOMS

Abstract: This system is comprised of an insulated access door (6), which makes for the closure of the cold room (4) in coming into contact with the door frame (1) fixed onto the entrance (2) of said cold room (4), and a quick opening door made up of a moveable sheet (8) and the corresponding means of activation (9, 10). These means of activation are to be fixed to the exterior of the cold room (4). There is also a longitudinal slit (7) fixed onto the door frame (1) so that the sheet (8) can pass, this sheet (8) being able to effect the closure either in front of or behind the insulated door (6). The system includes a stopper device (7) which can close the slit (7) in order to minimise the temperature loss through same, and some means (71 and 161) of heating the slit (7) and some guides (16) on which the sheet (8) moves to its open or closed position.

Description: AIM OF THE INVENTION This invention refers to a closing system for refrigerated cold rooms; this being for the type that includes an insulated access door that makes the seal when coming into contact with the door frame which is installed at the entrance to the cold room; and a quick opening door designed to minimise the changes of temperature whilst the insulated door remains open. Certain construction characteristics are present which allow the quick opening door to be integrated into the insulated door frame and make the closure of the cold room together with it; however the means of activating it are to be found on the exterior. BACKGROUND TO THE INVENTION The refrigerated cold rooms have at the openings of the entrance, a door frame around their edge onto which the insulated access door closes. One of the problems to be solved in these types of refrigerated cold rooms is that when the insulated access door is opened temperature changes occur on the inside of the cold room. These temperature changes can give rise to different disadvantages, such as the deterioration of the products which are being preserved, temperature oscillations which can be serious for the goods that are being stored and the increase in the energy consumption by the refrigeration equipment. Some of the most used solutions in order to solve this problem are based on the use of plastic curtains made up of a series of layers of plastic strips in the automation of the insulated door, which does not have a high opening and closing speed, and in the use of doors with a high opening speed, both allow access to the cold room and at the same time, reduce the exposure time of the cold room to the temperature of the outside due to the high opening-closing speed. The curtain of strips are sited in the opening of the entrance to the cold room and form a barrier behind the insulated access door; these curtains when pushed by people, fork lift trucks or any other element allow entrance or egress to the cold room. The main problems with these curtains are the ease with which they tear on being trapped by the transport fork lift trucks and that on passing through they offer resistance by rubbing against the products which can cause said products to fall, especially when these are piled up, for example onto fork lift trucks. The quick opening doors are made up of flexible or rigid sheet, which is moved by some method of action which produces the opening or closing of the access opening. These quick opening doors can be installed irrespective of the way which the sheet moves either vertically or laterally and using differing systems of detection and automation. The installation of these quick opening doors is carried out either on the inside of the cold room, behind the insulated access door or equally on the outside of the cold room. In the first case the detection and activating components and mechanism of the quick opening door will be on the inside of the cold room, making the final cost of the system considerably more expensive, especially in the case of low temperature cold rooms. In the case of the quick opening door located on the outside of the cold room, in front of the insulated door, it is essential to erect some type of ante chamber which has the insulated door in its interior, likewise the closure system for same, and therefore its installation is made considerably more complicated. DESCRIPTION OF THE INVENTION Patent N° FR-A-2.747.182 refers to a system of closure (a lock) for the cold room in which the use of a quick door is provided, said system being in accordance with the preamble of claim 1. The door is made up of an element of lamination with some cross members to reinforce it, as explained, located in front of or behind the insulated access door to the lock or to the cold room, driven by a driving mechanism and having capacity to be rolled up on a drum. The said system and drum being installed on the outside of the closure and of the cold room to which it gives access. In order to solve the problems mentioned, the closure system of the cold rooms has been thought up. It exploits the advantages of the quick opening automatic doors, it allows the installation of the activation to be carried out on the outside of the cold room. The closing strip is between the insulated access door and the cold room or vice versa and it makes use of the door frame of the insulated door for the guidance of the quick door. In accordance with the invention, as defined in claim 1, this closure system is of the type which can be understood as: a surrounding door frame on the entrance to the cold room, an insulated access door which acts on the exterior side of the door frame fashioning the closure of the cold room and a sheet which, activated at the right moment, brings about the opening or closing of the access opening to the cold room, the laminate and its motorization forming the assembly of a quick opening door designed to minimise the temperature variation in the interior of the cold room whilst the insulated access door of same remains open. The system of the invention is such that the surrounding door frame of the entrance opening to the cold room has a front section and a back section which protrude from the cold room wall, the laminate sheet of the quick opening door sliding by one or several slits located in any point of the doorframe threshold. The take up system for the laminate sheet is suitably installed by means of a support structure on the outside of the cold room, parallel to the frame side which is provided with the slit for the laminated sheet to pass. The installation of the take up system of the laminate sheet, likewise has motorization on the outside of the cold room, preventing these elements from having to bear the attacks that are suffered on the inside of the cold room. In order to minimise the temperature variation by means of the slit along which the sheet passes, the system has been planned to include a stopper device to facilitate its closing. Said stopper device can be made up of some materials having similar characteristics to the sheet, by a device which is activated by the insulated access door or by the sheet itself, or equally by a device automatically activated by outside elements or by some flexible profiles installed in the slit itself and which permanently act on the sides of the sheet without preventing its movement. The system has been planned to include some means of heating. There are intended to avoid the formation of ice both on the mentioned slit and equally on the sheet guides, since this could prevent the correct working of the quick access door. DESCRIPTION OF THE DRAWINGS In order to complement the description that is being made and with the aim of helping to give a greater understanding of the nature of the invention a set of drawings is attached to this description. The drawings also form an integral part of same, and are as an illustrative basis and are not limiting to that which is being represented. Figure 1 shows a front view of a cold room provided with the closure system which is the object of the invention and in which the sliding track of the insulated access door has been partially shown. In this figure two sections have been carried out of the door frame in order to allow the heating means of the slits and the side tracks to be seen. Figure 2 shows a sectioned view in perspective of the closure system, by a vertical plan, which passes through the middle area of the entrance to the cold room. Figure 3 shows a schematic view of the bars of the stopper device provided one on each side of the flexible sheet and slightly away from the vertical part of the door frame. Figure 4 shows a detail of a variant of the slit stopper device in order for the sheet to pass. Figure 5 shows a detail of another variant of the slit stopper device in order for the sheet to pass. PREFERRED EMBODIMENT OF THE INVENTION As can be seen in the attached drawings of the closure system which is the object of the invention, there is a door frame (1) installed on the entrance opening (2) defined on the wall (3) of a cold room, whose interior is marked with the reference (4). A section of the front of the door frame (1) protrudes, towards the outside of the cold room (4), from the plan defined by the wall (3), to which a guide is found fixed (5) on which the insulated access door is moved (6), which governs the establishing of the closure of the cold room (4) when coming into contact with the door frame(1). On the upper part of the door frame (1) there is, on the part which protrudes from the wall (3), a longitudinal slit (7) so that the flexible sheet can pass (8) which works in association with a revolving drum (9) onto which it can roll or unroll depending on the direction that the motor (10) which controls it is turning. The sheet (8), the drum (9) and the motor (10) fashion a quick opening door whose objective is to reduce to the minimum the change in temperature on the inside of the cold room (4) whilst the insulated access door (5) remains open. When the sheet unrolls (8) it closes the entrance (2). This is placed further inside in respect of the front surface of the door frame and therefore behind the position that the door occupies (6) in the closed position. The motor (10), which rolls the sheet (8) onto the drum (9), can be activated by different systems, which have not been represented because their description is not considered of interest. As can be seen from the figures, and especially in figure 2, the drum (9) is placed outside of the cold room (4) and the mechanical support elements (11) are suitably separated in respect of the guides, so that the sheet (8) slides on the inside of the cold room (4) to avoid losses from conduction, producing a break of the thermal bridge between said elements. Given that this slit (7) for the passage of the sheet (8) connects the inside of the cold room (4) with the exterior, a stopper device that closes said slit (7) is fixed onto the door frame (1) when the insulated access door (6) is closed, thus minimising the temperature variation. This slit (7) is capable of having some heating elements (71) on its inside which avoid the formation of ice caused by the temperature difference present from the interior to the exterior of the cold room. In the example carried out which is shown in figures 2 and 3, the slit (7) stopper device is represented schematically by two parallel bars (14) which are located on the upper side of the door frame (1), one on each side of the slit (7) and, therefore, one on each side of the sheet (8). At least one of these bars (14) can be moved by the action of the activation mechanism (15) which causes the two bars to come together (14) and hence the closure of the slit (7). In the variant carried out which is shown in figure 4, the slit (7) stopper device is represented by two profiles (12) fixed onto the sides of the sheet (8). In the variant carried out which is shown in figure 5, the stopper device is fashioned by some flexible profiles (13) fixed to the sides of the slit and that work in a permanent manner on the sheet (8) without hindering its movement. On the vertical sides of the door frame (1) some guides are found (16) in order to guide the sheet (8) along its path to the open or closed position. These guides can have some method of heating (161) provided in order to avoid, if it is necessary, the formation of ice in same. It is not considered necessary to make the description more complete as any expert in this subject can understand the scope of the invention and the advantages that derive from it. The terminology used in the drafting of this description is always to be taken in the widest sense and is not limiting. The materials, shape, size and arrangement of the elements are capable of being varied if and when it does not assume a modification of the essential nature of the invention, defined by the following claims.

Claims: Closure system for refrigerated cold rooms; of the type that is made up of a surrounding door frame (1) to be fixed onto the entrance opening (2) of the refrigerated cold room (4), an insulated access door (6) for establishing the closure of the cold room (4) on coming into contact with the door frame (1), and a sheet (8) which on being extended or rolled up by supporting and driving means (9-11) is respectively positioned in a closed or an open position of the cold room (4), said sheet (8) with its supporting and driving means on the outside of the cold room (4) constituting a quick acting door which is designed to minimise the temperature losses whilst the insulated access door (6) remains open; characterised in that the surrounding door frame (1) integrates a part which, in position, protrudes from the wall (3) of the cold room and has a long slit (7)on at least one of its sides, in order for the flexible sheet (8) to pass, said sheet; when in the closed position, being situated on an intermediate plane relative to the door frame (1), either in front of or behind the access door (6) which sheet (8) and being guided, in use, by at least one groove (16) made on the internal side of the door frame (1). Closure system, according to claim 1, characterised in that said surrounding door frame, when located in the opening (2) of the entrance to the cold room (4), has a part at the front and another part at the back which protrudes from the wall (3) of the cold room, the flexible sheet (8) sliding along one or several grooves (16) situated at any point of the internal side of the door frame to which it has access through the slit (7). Closure system according to claim 1, characterised in that the part of the door frame which protrudes from the wall (3) is a front part, having vertical guiding grooves (16), directly opposite the continuation of the slit (7) in order to guide the side edges of the sheet (8): Closure system, according to one of claims 1 to 3 characterised in that the supporting and driving means is made up of a drum (9) in association with a motor (10), which are installed on a support structure (11), on top of the door frame (1) and suitably separated in respect of the at least one guiding groove (16) along which the sheet (8) slides along. Closure system, according to one of claims 1 to 4 characterised in that a stopper device is included which is in charge of closing the slit (7), minimising the temperature variation by means of same, when the cold room (4) is closed by means of the insulated access door (6). Closure system, according to claim 5 characterised in that the stopper device is made up of some profiles (12) common to the sheet (8). Closure system, according to claim 5 characterised in that the stopper device is made up of some flexible profiles (13) fixed to the sides of the slit (7) and which work permanently on the sheet (8) without preventing its movement. Closure system, according to claim 5 characterised in that the stopper device of the slit (7) is made up of two parallel bars (14), at least one of which is mobile, activated by an actuator mechanism governed by external elements, by the access door (6) or by the sheet itself (8), separating or drawing together said bars (14) respectively determining the opening or closing of the slit (7). Closure system, according to one of claims 1 to 3 characterised in that at least one of the guiding grooves (16) for the guided movement of the sheet (8) has some means of heating (161) intended to prevent the formation of ice on said guiding grooves. Closure system, according to claim 1 characterised in that the slit (7) has some means of heating (71) aimed to prevent the formation of ice onto same.

Inventors: IGLESIAS BALLESTER MIGUEL ANGE, IGLESIAS BALLESTER, MIGUEL ANGEL
Applicants: IGLESIAS BALLESTER MIGUEL ANGE, IGLESIAS BALLESTER, MIGUEL ANGEL
Application year: 2000
Main classification: F25D23
IPC codes: F25D23