ITRE20120064A1 - DOOR FOR REFRIGERATING FURNITURE - Google Patents

Description

DESCRIPTION

â € œDOOR FOR REFRIGERATED FURNITURE â €

TECHNICAL FIELD

The present invention relates to a refrigerator cabinet door and a refrigerator cabinet comprising said door.

PRE-EXISTING TECHNIQUE

As is known, many foodstuffs are stored in commercial establishments inside special refrigerated cabinets which also have the purpose of displaying the goods to the customer.

Frozen foods in particular are stored in refrigerated cabinets closed with doors that include doors in transparent materials, such as glass, such as to guarantee the thermal insulation of the cabinet and at the same time allow the customer to observe and choose the goods on display.

Generally these doors are of the traditional hinged type, and therefore have the drawback of being bulky when opening, that is, requiring a large empty space in front of the refrigerator cabinet, in order to be opened.

In order to solve this problem of overall dimensions during the opening phase, refrigerating cabinets are also known which comprise doors with sliding doors, which are able to slide in guide means associated with the cabinet itself.

However, these sliding doors have the drawback that their opening requires a relatively high effort on the part of the users.

In fact, the sliding doors are relatively heavy in themselves, especially considering that, having to thermally insulate the refrigerator cabinet, the material that constitutes them is relatively thick. Furthermore, gaskets are generally interposed between the sliding doors and the refrigerator cabinet, which are necessary to thermally insulate the refrigerator cabinet, but which oppose, by friction, a rather high resistance to the relative sliding of the doors on the cabinet.

Another drawback of current sliding doors is that, having to be operated manually by a multiplicity of people in crowded environments such as shops, they can be unhygienic.

An object of the present invention is to overcome the aforementioned drawbacks of the known art, within the ambit of a simple, rational and relatively low cost solution.

These objects are achieved by the characteristics of the invention reported in the independent claim. The dependent claims outline preferred and / or particularly advantageous aspects of the invention.

<EXPOSURE OF THE INVENTION>

in particular, an embodiment of the invention makes available a door for refrigeration cabinets which comprises at least one sliding door able to slide in guide means associated with the cabinet, and a linear actuator able to operate said sliding door.

Thanks to this solution, the opening of the refrigerator cabinet takes place automatically, without manual operations by the operator, who therefore does not make any effort, since the resistance opposed by the weight of the sliding doors and the gaskets is easily won by the linear actuator.

It is hereby specified that a linear actuator generally means a device which comprises a fixed guide part, a movable part able to slide in a rectilinear direction on the fixed guide part, and means able to slide the movable part on the fixed part.

A linear actuator can be for example of the screw / nut screw type, ie it can comprise a nut screw integrally associated with the mobile part, a threaded shaft screwed into the nut screw and rotatably associated with the fixed part, and a motor able to rotate the threaded shaft. In this way, the rotation of the threaded shaft produces the linear sliding of the nut screw and therefore of the moving part associated with it.

Alternatively, a linear actuator can be of the belt or chain type, i.e. it can comprise a belt or a chain wound in a closed circuit around two toothed wheels associated with the fixed part, anchoring means adapted to constrain the movable part to a section of said belt or chain, and a motor adapted to rotate at least one of the two toothed wheels. In this way, the rotation of the toothed wheel drags the belt or chain, generating the linear movement of the mobile part anchored to it.

According to another alternative, a linear actuator can be a so-called linear electric motor, for example of the type which comprises an electromagnet supported by the movable part and a conductor, for example a metal plate, supported by the fixed guide part. In this way, the electromagnet generates an electromagnetic field which causes the generation of an induced magnetic field in the conductor. This magnetic field is opposite to the original field and, due to the repulsion between the two fields, causes the translation of the moving part.

According to a preferred aspect of the invention, the linear actuator of the door in question is however a linear actuator with permanent magnets.

This type of linear actuator has the advantage of being rather simple, inexpensive and easy to manufacture. Furthermore, said permanent magnet linear actuator is silent and therefore suitable for applications in crowded environments.

An example of a permanent magnet actuator can comprise a fixed guide part provided with a series of permanent magnets arranged along the sliding direction, and a mobile part provided with at least one electric winding, crossed by an electric current, for the generation of a field. variable magnetic, which interacts with the magnetic field of the permanent magnets of the fixed part and determines the translation of the moving part.

Alternatively, a preferred aspect of the invention provides that said linear actuator with permanent magnets comprises a fixed part able to be integrally constrained to the refrigerator cabinet, a movable part slidingly coupled to the fixed part and able to be integrally constrained to the sliding door, a first series of permanent magnets placed on one of said parts and developing in the sliding direction, and a second series of permanent magnets, facing said first series of magnets and carried by a rotor element able to rotate with respect to the first series of permanent magnets .

In particular, the first series of permanent magnets can be integral with the moving part, while the rotor element can be associated with the fixed part and be coupled to an electric motor able to set it in rotation.

Thanks to this solution, the magnets of the second series are placed in rotation with respect to the magnets of the first series, so as to generate a magnetic interaction that causes the moving part to slide with respect to the fixed part.

Not including electric windings, this type of linear actuator heats up less than the usual linear electric motors, making it therefore particularly suitable for applications in refrigerated cabinets.

According to another aspect of the invention, said linear actuator can be directly covered with heat-insulating material.

In this way it is possible to protect the linear actuator from the low temperatures of the refrigerator cabinet, in particular avoiding phenomena of differentiated expansion of the components which could damage the actuator or compromise its operation.

A further aspect of the invention provides that the door may include a push-button panel suitable for controlling the linear actuator, to operate the sliding of the sliding door.

Thanks to this solution, the door can be activated in a very simple and convenient way.

Alternatively, the linear actuator could be controlled by a proximity sensor, for example by a photocell.

Thanks to this solution, contact of the operatorâ € ™ s hand with any element of the door would not be necessary, considerably improving the hygiene of the invention and therefore making it particularly suitable for applications in crowded environments.

Another aspect of the invention provides that the door can comprise a pair of the aforementioned sliding leaves, each of which is operated in sliding by a respective of said linear actuators.

Thanks to this solution, only one sliding door of the refrigerator cabinet can be opened individually, in order to limit its energy consumption.

A further aspect of the invention provides that said sliding doors are arranged on parallel and staggered planes.

Thanks to this solution it is advantageously possible to open only one sliding door at a time.

A further aspect of the invention provides that said doors are individually adapted to slide between a closing configuration of the piece of furniture, in which they are side by side, and an opening configuration of the piece of furniture, in which they are substantially superimposed on each other.

In this way the doors are able to move one overlapping the other, so as not to protrude beyond the refrigerator cabinet and therefore limiting the overall dimensions of the door to a minimum when opening.

Another embodiment of the invention makes available a refrigerator cabinet which comprises the door described above.

This embodiment substantially achieves the same advantages listed above, in particular the advantages relating to door automation.

An aspect of this second embodiment provides that the piece of furniture may comprise a compartment suitable for accommodating the linear actuator, said compartment being covered, internally and / or externally, by a heat-insulating material.

This aspect provides an alternative solution to protect the linear actuator from the low temperatures of the refrigerator cabinet, and therefore to avoid damage or malfunction of the actuator itself.

BRIEF DESCRIPTION OF THE DRAWINGS

Further characteristics and advantages of the invention will become evident by reading the following description provided by way of non-limiting example, with the aid of the figures illustrated in the attached tables.

Figure 1 is an axonometric view of the refrigerator cabinet.

Figure 2 is the section according to plane II-II of figure 1.

Figure 3 is the section according to plane II-II of figure 1 with a door in the opening configuration.

Figure 4 is the section according to plane II-II of figure 1 with the other door in the opening configuration.

Figure 5 is a longitudinal section of one of the linear actuators with the leaf in the closed configuration.

Figure 6 is the section of figure 5 with the door in the opening configuration.

Figure 7 is the section according to plane VII-VII of figure 5.

<DETAILED DESCRIPTION>

With particular reference to these figures, the numeral 10 globally indicates a refrigerator cabinet, of the type suitable for display in commercial activities such as shopping centers and food shops. Said refrigerator cabinet 10 comprises a front face, which comprises an opening 11 which allows access to the refrigerated compartment inside the cabinet 10. This opening 11 is designed to be closed by a door 20. The door 20 comprises a pair of sliding doors 21 and 22, which are able to slide on respective guide means associated with the refrigerator cabinet 10. The doors 21 and 22 are preferably made of glass, or other transparent material, to allow the customer to observe and choose the goods displayed inside the refrigerator cabinet 10.

The sliding doors 21 and 22 are arranged on two parallel and staggered levels. In this way, the doors 21 and 22 are able to slide individually between a closing configuration of the cabinet, in which they are substantially side by side (Figures 1 and 2), and an opening configuration of the cabinet, in which the doors 21 and 22 are substantially overlapping (Figures 3 and 4). In this way, the opening 11 can only be partially opened, in practice substantially half, in order to limit energy dispersion when opening the refrigerator cabinet 10.

As illustrated in figures 2 to 4, each sliding door 21 and 22 is adapted to be operated in sliding by a respective linear actuator 30. The linear actuators 30 can be received and hidden inside an associated cover 12 to the refrigerator cabinet 10.

In general, each linear actuator 30 comprises a fixed part 31, fixed integrally to the refrigerator cabinet 10, for example by means of brackets 13, and a movable part 32 slidingly associated with the fixed part 31 and fixed integrally to the respective sliding doors 21 and 22 by means per se known in the art, for example fixing screws.

In the exemplary and non-limiting embodiment shown in the figures, the linear actuators 30 are both associated with the sliding leaves 21 and 22 at their upper edge and in a side-by-side position, so that one of them is arranged towards the inside of the refrigerator cabinet 10 while the other is arranged towards the outside.

Both linear actuators 30, or at least the one facing towards the inside of the refrigerator cabinet 10, can be advantageously coated, integrally or partially, with a heat-insulating material, which is able to protect them from the low internal temperatures of the refrigerator cabinet 10.

Alternatively, both linear actuators 30, or at least the one facing the inside of the refrigerator compartment, could be accommodated and protected inside a compartment specifically obtained in the refrigerator cabinet 10, for example in the protective casing 12, which is advantageously lined internally and / or externally with heat-insulating material, for example expanded polystyrene or polyurethane foams.

According to other embodiments, the linear actuators 30 could be associated with the respective sliding doors 21 and 22 at the upper edges, but not in a side-by-side position, but above the doors themselves.

Going into more detail, the linear actuators 30 used in this embodiment are linear actuators with permanent magnets, i.e. of the type described below with the aid of Figures 5 to 7.

The movable part 32 of each linear actuator 30 comprises a sliding bar, which is provided with grooves suitable for sliding on special rails 33 suitably made in the fixed part 31. In this way, the rails 33 also act as guide means for the relative sliding door.

A first series of permanent magnets 34 is integrally associated with the mobile part 32, for example by means of glue or screws. Said first series of magnets 34 is arranged along the sliding direction and the magnets 34 are spaced apart and have alternating polarity. : one magnet with external face with positive polarity (+) and one magnet with external face with negative polarity.

The fixed part 31 of each linear actuator 30 comprises a rotor element 35, facing the first series of magnets 34, which comprises a second series of permanent magnets 36. In particular, the rotor element 35 comprises a shaft 351 on which A support 352 is keyed to house the second series of magnets 36. The shaft 351 is coupled to an electric motor 353 by means of a relative reducer 354. The electric motor 353 is connected to an electric power supply and is controlled by a push-button panel 37 installed on the refrigerator cabinet 10 (see fig. 1).

The magnets 36 of the second series are arranged aligned along the axis of the rotor element 35, in parallel rows and arranged circumferentially around said rotation axis, so as to have polarity out of phase by a predetermined angle. For example, in the embodiment shown by way of non-limiting example in Figures 5 to 7, the support 352 has a hexagonal axial section. On this support with hexagonal section 352, the magnets 36 of each row are arranged on a respective face, side by side and with alternating polarity. The polarities of the magnets 36 lying on the same face are also opposite with respect to the respective magnets of the adjacent face, resulting therefore out of phase by 60 °.

In light of the above, the operation of door 20 is as follows.

By operating the electric motor 353 through the push-button panel 37, the rotor element 35 is set in rotation and with it the second series of magnets 36. The magnets 36 of the second series interact, in rotation, with the magnets 34 of the first series which are fixed on the mobile part 32. Thanks to the forces of mutual repulsion and attraction, generated by the magnets of the first and second series 34 and 36, the translation of the mobile part 32 is generated, and at the same time of the respective leaf 21 or 22, along the direction of sliding in one direction, for example in the opening direction. By activating, by means of the push-button panel 37, the rotation of the rotor element 35 in the reverse direction, the sliding of the mobile part 32 in the closing direction is commanded.

As an alternative to the push-button panel 37, the operation of the electric motor 353 can be controlled by proximity sensors, for example photocells, installed integral with the refrigerator cabinet 10, in this case the opening of each sliding door 22 and 23 is controlled by the presence of a body, for example the operator's hand, near the door 20 itself, while the removal of the said

Claims (12)

CLAIMS 1. Door (20) for a refrigerator cabinet (10) comprising at least one sliding door (21, 22) able to slide on guide means (33) associated with the cabinet (10), characterized in that it comprises a linear actuator (30) adapted to slide said sliding door (21, 22). Door (20) as per claim 1, wherein said linear actuator comprises a linear actuator (30) with permanent magnets. 3. Door as per claim 2, wherein said linear actuator (30) with permanent magnets comprises a fixed part (31) able to be integrally fixed to the furniture (10), a movable part (32) slidingly coupled to the fixed part (31 ) and able to be solidly constrained to the sliding door (21, 22), a first series of permanent magnets (34) placed on one of said parts (31, 32) and developing in the sliding direction, a second series of magnets permanent magnets (36), facing said first series of magnets (34) and carried by a rotor element (35) able to rotate with respect to the first series of permanent magnets (34). 4. Door (20) as per claim 3, in which said first series of magnets (34) is integral with the mobile part (32), and the rotor element (35) is associated with the fixed part (31) and It is coupled to an electric motor (353) adapted to set it in rotation. 5. Door (20) according to any one of the preceding claims, in which said linear actuator (30) is covered with heat-insulating material. 6. Door (20) as in any one of the preceding claims, comprising a push-button panel (37) adapted to control the linear actuator (30), to operate the sliding of the sliding door (21, 22). 7. Door (20) as in any one of the preceding claims, comprising a proximity sensor adapted to control the linear actuator (30), to activate the sliding of the sliding door (21, 22). Door (20) according to any one of the preceding claims, comprising a pair of said sliding doors (21, 22) each operated in sliding by a respective linear actuator (30). 9. Door (20) as per claim 8, in which said sliding doors (21, 22) are arranged on parallel and staggered planes. 10. Door (20) as per claim 9, in which said sliding doors (21, 22) are individually adapted to slide between a closing configuration, in which they are substantially side by side, and an opening configuration, in which they are substantially superimposed. Refrigerator cabinet (10) comprising a door (20) according to any one of claims 1 to 10. Refrigerator cabinet (10) as per claim 11, comprising a compartment suitable for accommodating at least one linear actuator (30) of the door (20), said compartment being covered with a heat-insulating material.