WO2017093956A1

WO2017093956A1 - An improved hinge, in particular for doors of isothermal containers

Info

Publication number: WO2017093956A1
Application number: PCT/IB2016/057297
Authority: WO
Inventors: Sara SECCHI
Original assignee: Polofin S.R.L.
Priority date: 2015-12-03
Filing date: 2016-12-02
Publication date: 2017-06-08
Also published as: EP3384116B1; PT3384116T; ITUB20156278A1; ES2842284T3; EP3384116A1

Abstract

An improved hinge (2), particularly for doors (4) of any isothermal containers (6), comprising a first hinge element (20) and a second hinge element (22), which are integral with the structure (6) of said isothermal container and said door (4), respectively, or vice versa, one of said two elements (22) being rotatable and axially sliding with respect to the other (20), and wherein: - said first hinge element (20) and said second hinge element (22) comprise two corresponding facing edges (31, 37) with respective cam-shaped profiles (35, 41) cooperating with each other to keep said door (4) in closed condition and automatically bringing it into such a condition due to a spring (24) acting on said first (20) or second element (22) and which can be urged by compression by the opening movement of the door (4), - the cam-shaped profile (35) of said first element (20) comprises two first stretches (50) inclined in opposite direction, which join at a first lower apex (36), - the cam-shaped profile (41) of said second element (22) comprises two second stretches (52) inclined in opposite direction, which join at a second lower apex (39), said hinge (2) being characterized in that said second hinge element (22) has, on the connection stretch (54) of the upper ends (53) of said second inclined stretches (52), in diametrically facing position with respect to said second lower apex (39), a single cavity (38) which can be engaged by the first lower apex (36) of said cam-shaped profile (35) of said first element (20) to bring/keep said door (4) in open configuration.

Description

AN IMPROVED HINGE, IN PARTICULAR FOR DOORS OF ISOTHERMAL CONTAINERS.

The present invention relates to an improved hinge, particularly for doors of any isothermal containers.

Hinges are known, which are to be applied to doors of cold rooms, refrigerated cabinets, deep freezers, blast chillers and any isothermal containers to allow the movement of the door itself about a vertical axis.

A common need in this type of application is associated with the need for the door to be moved automatically in its closing direction in order to avoid the isothermal container from inadvertently remaining open. This is currently obtained by making the hinge with two cylindrical sleeve-shaped elements mounted on a same pin and having the annular surfaces thereof facing, which are cam-shaped with a helical or otherwise inclined shape and are forced to adhere to each other. The upper sleeve is integral with the jamb of the isothermal container while the lower sleeve is integral with the door, and the shaped annular surfaces thereof are arranged so as to keep the door in closed condition and to automatically bring it into that condition each time it is moved away therefrom.

However, in order to allow the door to stably keep the open condition to facilitate the loading and/or unloading of material into/from the isothermal container, it is provided for the lower element of the hinge to have a flat stretch so that when the door is open, the hinge upper element cooperates with this flat stretch and thereby cancels both the effect of the weight of the door and the elastic reaction of the spring, and that is of the two causes which tend to bring the door back in closed condition. A drawback of this known solution consists in the fact that the condition of stably open door is not well defined, but covers a given angular range thereof. This lack of uniqueness of the condition of open door makes associating control and signaling systems of such a condition difficult.

Another drawback consists in the fact that the condition of door open may be kept stably only in the case of perfect verticality of the articulation axis of the hinges, and that is of the perfectly "level" installation of the isothermal container because even slight deviations from this configuration tend to automatically bring the door itself back in closed condition.

US4215449, US3518716, US2008/0276424 and US5138743 describe a hinge with two jointed sleeves which are integral with the container and the door, respectively, and which have two cam-shaped portions cooperating with each other so that the upper sleeve slides axially with respect to the lower one.

In particular, the profile of the lower sleeve in US4215449 has a cam- shaped profile at the front with two inclined stretches which join at the lower apex, and one rear stretch which is completely flat. Therefore, the opening rotation of the door is interrupted at about 1 10° when the tip of the cam- shaped profile of the upper sleeve comes into contact with the completely flat rear stretch. Such a solution is not satisfactory because it does not allow the door to be stably kept in open condition.

The profile of the lower sleeve in US 3518716 has a cam-shaped profile at the front with two inclined stretches which join at the lower apex, and two notches separated from each other by a rear stretch which is completely flat. In particular, each notch is made on the profile of the lower sleeve so as to define a 120° arc with the lower apex thereof. Therefore, when the door is opened more than 90°, the tip of the cam-shaped profile of the upper sleeve first enters the notch in order to keep a given open position of the door and then, upon a further rotation of the latter, the tip of the cam-shaped profile of the upper sleeve passes the notch and comes into contact with the rear flat stretch.

Such a solution also is not entirely satisfactory because in addition to requiring increased processing of the profile of the lower sleeve, it allows the door to be kept in open condition in a stable manner only when it is at 120°. In addition to hampering the maneuvering spaces about the isothermal containers, such an angular range is not sufficient to ensure the safety of operators, also considering that the doors of isothermal containers are particularly heavy.

Moreover, just due to the position of the notch along the profile of the upper sleeve, the user should open the doors and attempt to position it exactly at 120°; this means that the operator is not capable of easily, quickly and automatically identifying the condition in which the door remains stable in open condition. Not only, the dimensions of the notch do not allow the condition of door kept open to be ensured upon inevitable small stresses thereof.

The profile of the lower sleeve in US 51 38743 has two identical, diametrically facing cam-shaped steps. Such a solution is not satisfactory because it requires increased processing of the profile of the lower sleeve in order to make two cam-shaped steps with lower apexes having equal depth. Such a solution is not satisfactory because, for the automatic closure of the door, and in particular in order to cause it to pass from door in stable open condition to the closed condition, the user should accompany the door itself for a stretch of at least 90° so as to allow the tip of the cam-shaped profile of the upper sleeve to completely extend upwards the corresponding inclined stretch of the cam-shaped profile of the lower sleeve.

It is the object of the invention to eliminate these drawbacks and to make a hinge for a door of a cold room, refrigerated cabinet, deep freezer or "table", a blast chiller and any isothermal container which in addition to being capable of automatically bringing the door in closed condition when the door itself has reached a preset angular position, is also capable of keeping it in a preset and well-defined open condition even if the isothermal container is not perfectly level.

It is another object of the invention to make a hinge which does not involve any additional volume with respect to traditional hinges and which therefore may easily replace them, without resulting in any modification of the parts of isothermal container to which it is applied.

It is another object of the invention to make a hinge which ensures a gentle and regular movement of the door in the step of automatic movement towards the closed condition.

It is another object of the invention to make a hinge which stably keeps the open condition also in the presence of involuntary external stresses and which simultaneously optimizes/minimizes the stress to be applied on the door in order to activate the automatic passage thereof from the stable open condition to the closed one. It is another object of the invention to make a hinge which allows the operator to achieve the condition in which the door is kept open in a quick, easy and automatic manner.

It is another object of the invention to make a hinge in which the stable open condition of the door has an angular range greater than 130°, preferably of 165°, with respect to the closed condition thereof.

It is another object of the invention to make a hinge which has an alternative characterization with respect to traditional ones, both in terms of construction and performance.

It is another object of the invention to make a hinge which can be obtained in a simple, quick manner and with low costs.

All these objects, both individually and in any combination thereof, and other objects which will become apparent from the description below, are achieved, according to the invention, with a hinge, particularly for doors of any isothermal containers, as defined in claim 1 .

The present invention is hereinbelow further clarified in a preferred embodiment thereof, which is described by mere way of non-limiting example, with reference to the accompanying drawings, in which:

figure 1 shows a perspective diagrammatic view of a hinge according to the invention, applied to the door of a cold room,

figure 2 shows a perspective view of the hinge assembled,

figure 3 shows a side view of it,

figure 4 shows it according to the longitudinal section IV-IV in figure 5, figure 5 shows it according to the cross section V-V in figure 3,

figure 6 shows it according to the cross section VI-VI in figure 3, figure 7 shows an exploded side view of it,

figure 8 shows the detail of the two hinge elements, in an exploded and enlarged front view,

figure 9 shows a rear front view of it,

figure 10 shows an enlarged detail of figure 9, and

figure 1 1 shows a perspective view of the lower element only of the hinge.

As shown in the drawings, the hinge according to the invention, indicated globally with numeral 2, is applicable to a door 4 of an isothermal container, which in this particular case consists of a cold room 6. More particularly, the hinge forms the upper articulation element of door 4 to the structure of the cold room 6. It is applied for example, to the upper edge of door 4, close to a vertical corner thereof, and engages in an upper restraint blade 8 secured to the upper horizontal panel 10 of the cold room 6.

Moreover, hinge 2 cooperates with a different articulation element below, formed by a block 12 applied to the lower edge of door 4 at the vertical corner thereof and engages with a lower support blade 8' secured to the lower horizontal panel 14 of the cold room 6.

Hinge 2 according to the invention essentially comprises a parallelepiped shell or hinge body 16 to be incorporated in the thickness of door 4 and to be secured to the upper edge thereof by means of a horizontal bracket 18, which is integral with the shell itself.

There is accommodated in shell 16 the mechanism of the hinge, which comprises an upper element 20, a lower element 22, a spring 24 and a lower end plug 26. The upper element 20 comprises a pin 28, for example made of steel, and having a square-section upper portion 29 intended to engage with a corresponding square hole 30 made in the upper restraint blade 8, which is integral with the cold room 6, and a cylindrical portion 32 intended to be inserted into an axial hole made in the lower element 22 of the hinge.

Pin 28 is integral with an annular sleeve 34 intended to cooperate with the lower element 22 of the hinge, which is also formed by a similar annular sleeve 21 .

Conveniently, at least the parts of the sleeves 34 and 21 mutually in contact are made of plastic material with increased sliding and resistance to wear features. In particular, both the upper sleeve 34 and the lower sleeve 21 advantageously are made of polyoxymethylene-based acetal resin with increased sliding and resistance to wear features, preferably of DELRIN^® by DU PONT.

Advantageously, also pin 28 may be made of such a plastic material and in this case, preferably may be co-molded with the upper sleeve 34.

The upper annular edge of the upper sleeve 34 substantially is flat, orthogonal to the axis of pin 28, while the lower annular edge 31 thereof comprises a cam-shaped front profile 35 and a significantly flat rear profile 33. In greater detail, the cam-shaped profile 35, which extends over about 180° of the extension of the lower annular edge 31 has two symmetrical stretches 50 inclined in opposite direction, preferably having significantly spiral orientation, which are joined at the bottom in a kind of lower apex 36. The significantly flat rear profile 33 instead extends over the remaining 180° of the extension of the lower annular edge 31 . The lower sleeve 21 of the hinge has the axial cavity intended to be crossed by the cylindrical portion 32 of pin 28 of the upper element 20.

The lower sleeve 21 has an upper annular edge 37 which comprises a cam-shaped profile 41 which is complementary to the cam-shaped profile 35 of the lower annular edge 31 of the upper sleeve 34. In particular, the cam- shaped profile 41 of the lower sleeve 21 comprises two symmetrical stretches 52 inclined in opposite direction, preferably having significantly spiral orientation, which are joined at the bottom in a second lower apex 39 which preferably is defined by a kind of overturned saddle.

The upper ends 53 of the two inclined symmetrical stretches 52 in the lower sleeve 21 are connected at the back, that is over the other 180° of extension of the rear annular edge 37, by a stretch 54 which has, in position diametrically facing/opposite to the second lower apex 39, one cavity 38 alone which can be engaged by the first lower apex 36 of the cam-shaped profile 35 of the upper element 20 to bring/keep said door 4 in an open configuration of at least 130°, preferably of 165°, with respect to the corresponding closed configuration.

Conveniently, cavity 38 is defined on the upper annular edge 37 of the lower sleeve 21 so as to form the stroke end position for the opening movement of door 4.

Preferably, the middle of cavity 38 along the rear annular edge 37 of the lower sleeve 21 is diametrically opposite to the middle of the second lower apex 39.

Advantageously, the connection stretch 54 of the upper ends 53 substantially is flat. Preferably, cavity 38 is positioned in the middle of the connection stretch 54 interposed between the upper ends 53 of the two inclined symmetrical stretches 52.

Advantageously, the upper ends 53 of the two inclined symmetrical stretches 52 substantially are flat.

Advantageously, cavity 38 is shaped like a recess, that is like a depression which is not particularly accentuated. Conveniently, cavity 38 may have a central base 60 (which preferably corresponds to the deepest area thereof) which substantially is horizontal and is interposed between two inclined or conveniently curved stretches 65 (cfr fig. 10), or may have a completely arched profile.

Conveniently, the recessed depth 49 of cavity 38 (and preferably of the deepest area thereof), which is defined with respect to the upper ends 53, is lower, and preferably is significantly lower, than the one of the second lower apex 39. In particular, cavity 38 is recessed by 1 to 2 mm, preferably by about 1 .2 to 1 .6 mm, with respect to the upper ends 53 of the two inclined symmetrical stretches 52, while the second lower apex 39 is recessed by at least 10 mm, preferably by about 12 to 16 mm, with respect to the upper ends 53 of the two inclined symmetrical stretches 52. Preferably, the recessed depth of the second lower apex 39 with respect to the upper ends 53 is at least ten times higher than the one of cavity 38.

Advantageously, the maximum distance 59 between the inner facing profiles 57 of the inclined stretches 52 is less than the chord 61 underlying the annular extension of cavity 38 (cfr fig. 1 0). Preferably, distance 59 between the inner facing profiles 57 of the inclined stretches 52 corresponds to about half of said chord 61 . Conveniently, the first lower apex 36 of the upper sleeve 34 has a significantly smaller lower contact surface 69 than the annular extension 61 of cavity 38 in order to ensure the stability of the condition in which door 4 is kept open. Preferably, the contact surface 69 of the first lower apex 36 of the upper sleeve 34 is smaller than the annular extension of the horizontal central base 60 of recess 38.

The lower edge of sleeve 22 instead is involved by an annular projection 40 which contours the axial cavity crossed by the cylindrical portion 32 of pin 28 and is intended to engage inside spring 24.

The lower sleeve element 22 is also involved by a pair of outer longitudinal ribs 42, which cooperate with grooved guides 44 obtained in the hinge body 16 and serving to avoid the rotations of the lower element 21 about the axis thereof, while allowing it axial movements along the inner cavity of the body itself.

Spring 24, which is partly compressed between the lower sleeve element 22 of the hinge and the end plug 26, resting on the bottom of shell 16, serves the function of pressing said lower sleeve element 22 against sleeve 34 of the upper element 20 so as to keep the two cam-shaped profiles 35, 37 of the two elements themselves adhering to each other.

The arrangement of the various parts is such that when door 4 of the cold room 6 is closed, spring 24 is slightly preloaded, while the lower apex 36 of the cam-shaped profile 35 of the hinge upper element 20 is slightly offset with respect to the saddle-shaped lower tip 39 of the cam-shaped profile 37 of the hinge lower element 22 so as to force door 4 to keep the closed condition thereof due to the preloading of spring 24. The opening manoeuver of the door results in a rotation thereof about the vertical axis passing through the pin 28 of hinge 2 and through a lower pin 46, which is integral with the lower support blade 8' and engages an axial hole made in the lower block 12.

During this opening movement, the upper element 20 of the hinge remains fixed with respect to the restraint blade 8 due to the square shape of the upper stretch 29 of pin 28 thereof and of the square hole 30 of the upper restraint blade 8, and it cannot rotate with door 4, while the lower element 21 of the hinge rotates with door 4, given the engagement of the longitudinal ribs 42 thereof in the grooved guides 44 of shell 16.

This rotation of the lower element 22 of hinge 2 with respect to the upper element 20 induces a related sliding movement of the two paired cam- shaped profiles 35, 37, with subsequent axial movement of the lower sleeve 21 of the hinge with respect to the upper sleeve 34, and subsequent compression of spring 24.

During this rotation movement of the lower sleeve 21 with respect to the upper sleeve 34, apex 36 of the latter slides along the cam-shaped profile 37 of the first until, at an open position greater than 130° of door 4, preferably of 165°, said apex 36 reaches recess 38 in the upper edge of sleeve 22 and ensures also the open position of door 4 is stably kept.

The closing manoeuver of door 4 is performed with a rotation thereof and subsequent disengagement of apex 36 from recess 38.

Once this disengagement is performed, and once the cam-shaped profiles 35, 37 start cooperating with each other, the elastic reaction of spring 24 tends to automatically bring door 4 back to the closed condition of the cold room 6.

It is apparent from what is said that the hinge according to the invention is more advantageous than traditional hinges to be applied to the doors of cold rooms, refrigerated cabinets, deep freezers, blast chillers and other isothermal containers, and in particular:

- it ensures the door is kept in open condition, and rather automatically brings it back to such a condition even if it should be slightly moved away from that condition upon unavoidable stresses,

- it allows the condition in which the door is kept in open condition to be identified by the user in a simple and quick manner,

- it allows the door to be easily brought back by the user from the open condition to the closed condition without the need to accompany it for a stretch of at least 90°,

- it allows the door to stably keep an open condition of at least 130°, preferably of 165°, even if the isothermal container is not level,

- it has shape and volume similar to the ones of traditional hinges for any isothermal containers and may replace them without resulting in any additional volume,

- it ensures a gentle and regular movement of the door both in the movement it performs to reach the closed condition and in the movement it performs to reach the open condition,

- the processing required to make it is simple because each of the two elements of the hinge itself has one cam-shaped profile alone.

Claims

C L A I M S

1 . An improved hinge (2), particularly for doors (4) of any isothermal containers (6), comprising a first hinge element (20) and a second hinge element (22), which are integral with the structure (6) of said isothermal container and said door (4), respectively, or vice versa, one of said two elements (22) being rotatable and axially sliding with respect to the other (20), and wherein:

- said first hinge element (20) and said second hinge element (22) comprise two corresponding facing edges (31 , 37) with respective cam-shaped profiles (35, 41 ) cooperating with each other to keep said door (4) in closed condition and automatically bringing it into such a condition due to a spring (24) acting on said first (20) or second element (22) and which can be urged by compression by the opening movement of the door (4),

- the cam-shaped profile (35) of said first element (20) comprises two first stretches (50) inclined in opposite direction, which join at a first lower apex (36),

- the cam-shaped profile (41 ) of said second element (22) comprises two second stretches (52) inclined in opposite direction, which join at a second lower apex (39),

said hinge (2) being characterized in that said second hinge element (22) has, on the connection stretch (54) of the upper ends (53) of said second inclined stretches (52), in diametrically facing position with respect to said second lower apex (39), a single cavity (38) which can be engaged by the first lower apex (36) of said cam-shaped profile (35) of said first element (20) to bring/keep said door (4) in open configuration.

2. A hinge according to claim 1 , characterized in that said cavity (38) comprises a recess.

3. A hinge according to one or more of the preceding claims, characterized in that said cavity (38) has a substantially arched profile.

4. A hinge according to one or more of the preceding claims, characterized in that said cavity (38) has a substantially horizontal central bottom (60) interposed between two oblique stretches.

5. A hinge according to one or more of the preceding claims, characterized in that said cavity (38) has a substantially horizontal central bottom (60) interposed between two curved stretches (65).

6. A hinge according to one or more of the preceding claims, characterized in that the middle of said cavity (38) is diametrically opposite to the middle of said second lower apex (39) of the cam-shaped profile (41 ) of said second element (22).

7. A hinge according to one or more of the preceding claims, characterized in that said connection stretch (54) of the upper ends (53) of said second inclined stretches (52) is substantially flat.

8. A hinge according to one or more of the preceding claims, characterized in that the bottom (60) of said cavity (38) is defined at the middle of said connection stretch (54) which joins the upper ends (53) of said second inclined stretches (52).

9. A hinge according to one or more of the preceding claims, characterized in that the bottom (60) of said cavity (38) is positioned centrally between the upper ends (53) of said second inclined stretches (52).

10. A hinge according to one or more of the preceding claims, characterized in that the upper ends (53) of said second inclined stretches (52) are substantially flat.

1 1 . A hinge according to one or more of the preceding claims, characterized in that the depth, which is defined with respect to the upper ends (53) of said second inclined stretches (52), of the bottom of the cavity (38) is significantly less than the one of the second lower apex (39) of said second cam-shaped profile (41 ).

12. A hinge according to one or more of the preceding claims, characterized in that said cavity (38) is obtained on the edge (37) of said second element (22) so as to define the stroke end for the opening movement of the door (4).

13. A hinge according to one or more of the preceding claims, characterized in that said cavity (38) has an upper lateral extension (61 ) at the maximum distance (59) between the inner facing profiles (57) of said second inclined stretches (52).

14. A hinge according to one or more of the preceding claims, characterized in that the bottom of said cavity (38) has a lateral extension which is greater than the contact surface defined on the tip (69) of the first lower apex (36) of the cam-shaped profile (35) of said first element (20).

15. A hinge according to one or more of the preceding claims, characterized in that said second hinge element (22) has an upper edge (37) which cooperates with a corresponding lower edge (31 ) of said first element (20), said upper edge (37) of said second hinge element (22) exclusively consists of: - said two second stretches (52) inclined in opposite direction which join at a second lower apex (39),

- a substantially flat connection stretch (54) of the upper ends (53) of said second inclined stretches (52), and

- one cavity (38) alone which is defined on said connection stretch (54) in position diametrically opposite to said second lower apex (39).

16. A hinge according to one or more of the preceding claims, characterized in that said second inclined stretches (52) of said second lower hinge element (22) are complementary to the first inclined stretches (50) of said upper first hinge element (20).

17. A hinge according to one or more of the preceding claims, characterized in that it comprises a hinge shell (16) which is integral with the door (4) and in that:

- said first hinge element (20) is accommodated in said shell (16) and is constrained in rotation to the structure (6) of said isothermal container,

- said second hinge element (22) is accommodated in said shell (16), is integral in rotation with said shell (16) and is axially sliding both with respect thereto and with respect to said first element (20),

- said spring (24) is accommodated in said shell (16).

18. A hinge according to one or more of the preceding claims, characterized in that said first hinge element (20) comprises an annular sleeve (34) intended to cooperate with a corresponding annular sleeve (21 ) of said second element (22) of the hinge, said two facing edges (31 , 37) of said first (20) and second hinge element (22) being defined in the corresponding annular sleeves (34, 21 ) of said elements (20, 22).

19. A hinge according to one or more of the preceding claims, characterized in that said first hinge element (20) also comprises a pin (28) which is integral with the structure (6) of said isothermal container and is provided with a cylindrical portion (32) intended to be inserted into an axial hole made in the sleeve (21 ) of the second hinge element (22).

20. A hinge according to the preceding claim, characterized in that said pin (28) of said first hinge element (20) is co-molded with said annular sleeve (34).

21 . A hinge according to one or more of the preceding claims, characterized in that the facing edges (31 , 37) of said sleeve portions (34, 21 ) of said first element (20) and of said second hinge element (22) are made of plastic material with increased sliding and resistance to wear features.

22. A hinge according to one or more of the preceding claims, characterized in that said first hinge element (20) and said second hinge element (22) comprise sleeve portions (34, 21 ) made of polyoxymethylene- based acetal resin.

23. A hinge according to one or more of the preceding claims, characterized in that in condition of hinge mounted and closed door (4), said spring (24) is kept in preloaded condition.

24. A hinge according to one or more of the preceding claims, characterized in that in condition of hinge mounted and closed door, the first lower apex (36) of the first element (20) is slightly offset with respect to the second lower saddle-shaped apex (39) obtained in the second element (22), in the sense of inducing the closing of the door (4) due to the effect of the preloading of said spring (24).

25. A hinge according to one or more of the preceding claims, characterized in that said second element (22) comprises at least one outer longitudinal rib (42) which cooperates with a corresponding grooved guide (44) obtained on the hinge body (16) in order to avoid the rotations of said second element (22) about the axis thereof, while simultaneously allowing it axial movements along the inner cavity of the body itself.

26. An isothermal container, preferably a cold room, comprising a containment structure (6) and a door (4) which is articulated to said structure (6) by means of a hinge according to one or more of the preceding claims.