EP2128369A2

EP2128369A2 - Hinge for wings or doors

Info

Publication number: EP2128369A2
Application number: EP09160265A
Authority: EP
Inventors: Angelo Vanini
Original assignee: Nuova Star SpA
Current assignee: Nuova Star SpA
Priority date: 2008-05-20
Filing date: 2009-05-14
Publication date: 2009-12-02
Also published as: ITBO20080037U1; EP2128369A3

Abstract

A hinge (4) for wings and/or doors (3), in particular doors of electrical appliances (1) such as ovens, dishwashers or the like, comprises a first box-shaped structure which can be fixed to a frame (2), a second box-shaped structure (5) which can be fixed to the door (3) and which has a main direction of extension (B), a connecting lever (6) between the first box-shaped structure and the second box-shaped structure (5), the second structure (5) pivoting at a pin (9) connected to the lever (7) and being able to move with a tilting action about the pin (9) at least between a door (3) closed condition and a door open condition, a spring (12) connected to the second box-shaped structure (5) and designed, when it is elastically deformed, to generate an elastic reaction force which opposes door (3) opening, means (16) for adjusting the intensity of the elastic reaction force.

Description

The present invention relates to a hinge for wings or doors, and in particular to a hinge which can be used to connect doors of electrical appliances, such as ovens, to the respective supporting structures.
In the following description and by way of example only, without limiting the scope of the invention, the present invention is described with reference to an oven.
Hinges of this type usually consist of two separate parts, both having a box-shaped structure and kinematically connected to each other.
More precisely, the first of said parts is fixed to the oven structure at one side of the oven mouth, whilst the second part is fixed to one edge of the door, which in that way is rendered movable, with a tilting action, relative to said oven mouth.
A lever is operatively interposed between the box-shaped structures, a first end of the lever being rigidly connected to the first box-shaped structure and a second end of the lever pivoting, by means of a pin, at the second box-shaped structure.
Therefore, during door rotation, in the direction in which it opens or in the opposite direction in which it closes, the second box-shaped structure rotates about the pin which forms a pivoting axis for the door.
The lever is acted on by elastic elements, interposed between the lever and the box-shaped structure connected to the door.
More precisely the elastic elements operate between this box-shaped structure and a rod positioned inside it. The free end of the rod, that is to say the end not interacting with the elastic elements, pivots at the above-mentioned lever.
During door rotation about its pivoting axis, the elastic elements oppose both the initial movement of the door away from the oven structure, and the subsequent door rotation and its consequent lowering as far as a position in which the oven mouth is completely open. Therefore, said types of hinges continuously apply on the door a force which tends to keep them in their oven mouth closing position.
The door, under the combined action of its own weight which promotes its descent and of the elastic elements which apply a braking action, completes its opening step with a gradual rotation. Therefore, in the configuration in which the door is completely open a condition of equilibrium is established between the torque applied by the weight of the door and the torque applied by the elastic elements and said configuration is stable.
Prior art hinges of the type described had the disadvantage of on each occasion requiring, to adapt to the possible different dimensions and weights of the doors, substitution of the elastic elements so as to guarantee that the equilibrium condition just described is achieved for each door. To overcome said disadvantage, hinge solutions were developed, even by the Applicant, in which the elastic elements, which is most cases consist of helical springs, have their own screw adjusting means, designed to vary their preloading condition by modifying the axial extension of the spring.
Said adjusting means are not without disadvantages. A first disadvantage is the fact that the adjusting screw requires a large number of turns about its axis to make even a minimal change to the axial extension of the spring. This is because, due to adjustment stability requirements, a thread with a reduced angle of inclination has to be used and, therefore, axial movement by the screw with each turn is minimal.
Moreover, the screw adjusting means do not guarantee lasting maintenance of the initial adjustment position set.
Another disadvantage linked to use of the screw adjusting means is the fact that the adjustment itself is extremely laborious and difficult to repeat from one hinge to another.
The present invention therefore has for an aim to overcome the above-mentioned disadvantages by providing a hinge for wings or doors which has a simple structure and practical and effective adjustment.
The technical features of the present invention, in accordance with the above aim, are clear from the content of the claims herein, in particular claim 1 and, preferably, from any of the claims directly or indirectly dependent on claim 1.
The advantages of the present invention are more apparent in the detailed description which follows, with reference to the accompanying drawings which illustrate a preferred, non-limiting embodiment of the invention, in which:

Figure 1 is a schematic perspective top view of an oven fitted with a door which is connected to it by two hinges made in accordance with the present invention;
Figures 2 and 3 are respective schematic perspective views, with some parts cut away or transparent to better illustrate others, of a preferred embodiment of a hinge in accordance with the present invention, in two different configurations for use;
Figure 4 is a schematic partial side elevation view of a hinge in accordance with the present invention in the configuration of Figure 2;
Figure 5 is a schematic partial front elevation view of a hinge in accordance with the present invention in the configuration of Figure 2;
Figure 6 is a schematic partial side elevation view of a hinge in accordance with the present invention in the configuration of Figure 3;
Figure 7 is a schematic partial front elevation view of a hinge in accordance with the present invention in the configuration of Figure 3.

With reference to Figure 1, the numeral 1 denotes as a whole an oven comprising a frame 2 to which a door 3 is connected by two hinges 4, which allow the door to rotate with a tilting action about a first horizontal axis A.
With reference to Figures 2 and 3, each hinge 4 comprises a first box-shaped structure, not illustrated, which is fixed to the oven 1 frame 2, and a second box-shaped structure 5 which is fixed to the door 3. The first box-shaped structure and the second box-shaped structure 5 are kinematically connected by a connecting lever 6.
The second box-shaped structure 5 has a substantially C-shaped cross-section and extends longitudinally along its own axis B, hereinafter also indicated as the main direction of extension of the second structure 5.
The connecting lever 6 comprises a first arm 7, designed to be rigidly connected to the first box-shaped structure, and a second arm 8 which is connected to the second box-shaped structure 5.
For the connection between the second arm 8 and the second box-shaped structure 5, the hinge 1 comprises a first pin 9 passing through a respective hole made at the end of the second arm 8 and coaxial with the axis A.
The hinge 1 also comprises a rod 10 positioned longitudinally inside the second box-shaped structure 5 and connected to its lower end 5a, by means of a second pin 11 parallel with the first pin 9 and passing through a respective hole made in an intermediate stretch of the second arm 8 of the lever 6.
Inside the second box-shaped structure 5 there is a helical spring 12, extending longitudinally in line with the rod 10, parallel with the axis B, and operating with a pulling action, as described in more detail below.
A first, lower end 12a of the helical spring 12 is connected to a hole made in the rod 10 and the second, upper end 12b of the spring, longitudinally opposite the first, lower end 12a, is connected to a hooking element 13 positioned at an upper end 5b of the second box-shaped structure 5.
As illustrated in the accompanying drawings, the spring 12 hooking element 13 has two longitudinally opposite end portions 13a, 13b which stably engage by resting on two respective slots 14 made in the same number of opposite lateral walls 15a, 15b of the second box-shaped structure 5. The lateral walls 15a, 15b, together with an intermediate wall 15c which is at a right angle to them, form said C-shape of the structure 5.
The hooking element 13 has a substantially flat shape and has the above-mentioned end portions 13a, 13b with a substantially quadrangular cross-section.
Between its two end portions 13a, 13b the hooking element 13 has an indented central body 13c, having two hollows designed for laterally holding the upper end 12b of the helical spring 12.
As is clearly illustrated in Figures 4 and 6, the slot 14 is approximately L-shaped, therefore having two arms 14a, 14b positioned transversally relative to each other. In detail, each slot 14 has a first arm 14a angled parallel with the above-mentioned direction B, and a second arm 14b substantially at a right angle to the first arm 14a and, therefore, angled transversally relative to the direction B.
For the hinge 4, the hooking element 13 forms means 16 for adjusting the spring 12 elastic reaction force.
For the hinge 4, the spring 12 constitutes an elastic element designed to generate a reaction force which opposes door 3 opening.
In practice, starting from a door 3 closed condition, not illustrated in the accompanying drawings, after door 3 operation by an operator, the hinges 4 cause at first a relatively rapid door 3 opening rotation covering a predetermined angular travel and then a gradual slowed opening, until a door 3 completely open condition is reached, illustrated in Figure 1.
The door 3, under the combined action of its own weight, which promotes its tilting descent, and the braking action caused by a moment M1 of force applied by the helical spring 12, completes its opening step with gradual rotation as far as the position illustrated in Figure 1.
The moment M1 is generated by the elastic reaction force applied by the spring 12 after the deformation induced on the spring 12 during door 3 opening.
To adjust the intensity of the moment M1 and consequently its braking action on the door 3 according to both the characteristics of the spring 12 and/or its state of wear, and according to the weight and dimensions of the door 3, the means 16 for adjusting the intensity of the spring 12 elastic reaction force are provided.
In particular, the adjusting means 16 comprise the hooking element 13 which can move between two different limit positions, a first illustrated in Figures 2, 4 and 5, and a second illustrated in Figures 3, 6 and 7.
The passage of the hooking element 13 between said two limit positions causes a variation in the position of the element 13 and the second box-shaped structure 5 relative to each other and, in particular, a change in the longitudinal extension of the spring 12 along its axis B. Said change in the longitudinal extension of the spring 12 involves a simultaneous variation in the elastic deformation of the spring 12.
In detail, as illustrated in Figures 4 and 5, the hooking element 13 is positioned vertically, meaning that the plane which it identifies is substantially parallel with the main direction of extension B of the second box-shaped structure 5. In its first limit position, the hooking element 13 has its end portions 13a, 13b with quadrangular cross-section engaged in the respective arms 14a of the slots 14 made in the walls 15a and 15b of the box-shaped structure 5.
The hooking element 13 is kept stably in its first position by the pulling action applied by the spring 12 in the direction shown by the arrow F, said pulling action keeping the end portions 13a, 13b in contact with the lower edge of the arms 14a of the slots 14.
Starting from the first position just described, with the use of a suitable lever tool, the hooking element 13 is rotated and translated until it adopts its second limit position, illustrated in Figures 6 and 7.
In said second position, the hooking element 13 is positioned horizontally, meaning that the plane which it identifies is substantially perpendicular to the main direction of extension B of the second box-shaped body 5. In said second limit position, the hooking element 13 has its end portions 13a, 13b with quadrangular cross-section engaged in the respective arms 14b of the slots 14 made in the walls 15a and 15b of the box-shaped structure 5.
Similarly to what was described with reference to the first position, the hooking element 13 is also kept stably in its second position by the pulling action applied by the spring 12 in the direction shown by the arrow F, said pulling action keeping the end portions 13a, 13b in contact with the lower edge of the arms 14b of the slots 14.
Use of the hinge in accordance with the present invention advantageously allows simple, effective and intuitive adjustment of the spring preloading between two different configurations.
Advantageously, the use of two hinges in accordance with the present invention allows the possibility of adjusting one hinge differently to the other, therefore increasing the possible adjustments of the overall force acting on the door of the electrical appliance.
Advantageously, if the hinge in accordance with the present invention is mounted on an electrical appliance and is initially used with the hooking element 13 in its second position in which the helical spring 12 adopts a configuration with less deformation, with use, following deterioration of the mechanical characteristics of the spring 12, the element 13 may advantageously be moved to its first position so that the spring 12 is brought to its configuration with greater deformation, meaning that the spring at least partly recovers its initial elastic reaction capacity.

Claims

A hinge for wings and/or doors (3), in particular for electrical appliances (1) such as ovens, dishwashers or the like, of the type comprising
- a first box-shaped structure which can be fixed to a frame (2),

- a second box-shaped structure (5) which can be fixed to the door (3) and has a main direction of extension (B),

- a connecting lever (7) between the first box-shaped structure and the second box-shaped structure (5), said second structure (5) pivoting at a pin (9) connected to the lever (7) and being able to move with a tilting action about the pin (9) at least between a door (3) closed condition and a door open condition,

- at least one helical spring (12) operatively connected to the second box-shaped structure (5) and designed, when it is deformed, to generate an elastic reaction force which opposes door (3) opening,

- means (16) for adjusting the intensity of said elastic reaction force, the hinge being characterised in that the adjusting means (16) comprise a helical spring (12) hooking element (13), the hooking element (13) being able to move between two limit positions in which the helical spring (12) adopts the same number of respective different deformed configurations.
The hinge according to claim 1, in which the helical spring (12) extends longitudinally parallel with the main direction of extension (B) of the second box-shaped structure (5), the hinge being characterised in that the hooking element (13) operatively engages with the helical spring (12) and is designed to change the longitudinal extension of the spring as it passes from one of said two positions to the other.
The hinge according to claim 2, characterised in that the hooking element (13) has two respective longitudinal end portions (13a, 13b) having a substantially quadrangular cross-section.
The hinge according to claim 3, in which the second box-shaped structure (5) has two opposite lateral walls (15a, 15b), characterised in that each of the walls (15a, 15b) has a respective slot (14) in which one of the longitudinal end portions (13a, 13b) of the hooking element (13) stably engages.
The hinge according to claim 4, characterised in that the slot (14) is at least approximately L-shaped, each arm (14a, 14b) of said L-shape forming a respective housing for the end portion (13a, 13b) with quadrangular cross-section, the positioning of said end portion (13a, 13b) in one or the other of the arms (14a, 14b) alternatively defining, for the hooking element (13), said two limit positions.
The hinge according to claim 5, characterised in that the arms (14a, 14b) of the L-shaped slot are angled so that one is substantially parallel with the main direction of extension (B) of the second box-shaped body (5) and the other is substantially transversal to said direction (B).
The hinge according to claim 6, in which the hooking element (13) has a substantially flat shape, characterised in that the end portions (13a, 13b) of the hooking element (13) stably engage in the arms (14a) which are angled parallel with the main direction of extension (B), thus defining a first limit position of the hooking element (13) in which the helical spring (12) adopts a configuration with greater deformation, and in contrast the end portions stably engage in the arms (14b) which are angled transversally relative to the direction (B), thus defining a second limit position of the hooking element (13) in which the helical spring (12) adopts a configuration with less deformation.