HINGE FOR OVEN DOORS OR THE LIKE Technical Field

The present invention relates to a hinge for oven doors or the like. Background Art In the field of the production of hinges for ovens or other similar devices, one of the main problems is linked to the structural complexity of said hinges, which inevitably affects production costs.

Hinges for doors of ovens or other similar devices are constituted generally by a first arm, to be fixed to the door for closing the chamber of the oven, and a second arm, which is articulated in some way to the first arm and is designed to be fixed to the structure of the oven.

A mechanism (generally also comprising a spring with a high elastic constant) is interposed between the first arm and the second arm and is adapted to allow the rotation of the first arm on the second arm according to a controlled motion, ensuring positions of stable equilibrium for the door when it is closed onto the chamber of the oven and when it is open thereon, as well as on intermediate positions.

The mechanism that manages the relative movement of the two arms of the hinge is generally very complicated, since it is constituted by many components, some of which also have a complex geometry.

This structural complexity of the hinges affects production costs significantly, in terms of cost for the provision of the individual components, in terms of cost of the equipment for providing such components, and in terms of assembly costs. It should also be noted that, as regards assembly, known hinges generally have a drawback.

This drawback is linked to the fact that the spring of the mechanism of the hinge, which as mentioned has a high elastic constant, tends to keep the first arm closed on the second arm (typically at an angle of approximately 90°), so as to match the configuration of the door closed onto

the chamber of the oven.

During assembly, this configuration of the hinge does not allow to fix it to the oven, since the first arm must be inclined with respect to the second arm by an angle comprised between 90° and 180°, in order to allow easy insertion of the end head of the second arm in a corresponding locking seat provided on the oven.

In view of the great force required to overcome the resistance of the spring and turn the first arm with respect to the second arm, many manufacturers are equipped with dedicated tools for "opening" the hinges during the assembly step.

Other manufacturers provide the hinge with a fork-like element which is pivoted, on the sides of the fork, to the second arm, surrounding part of the arm.

The fork-like element is used as an element for locking the rotation of the first arm on the second arm as an effect of the spring, since during the assembly step it is turned, interposing itself between the two arms.

The locking element, in addition to increasing the complexity of the structure, has the drawback of increasing the lateral space occupation of the second arm, with size problems which are not easy to solve, if one considers the need to try to reduce the dimensions of the hinge components (while of course maintaining the same mechanical strength). Disclosure of the Invention

The aim of the present invention is to provide a hinge for doors of ovens or the like which solves the problems noted in known types. Within this aim, an object of the present invention is to provide a hinge for doors of ovens or the like which is structurally simple.

Another object of the present invention is to provide a hinge for doors of ovens or the like which allows easy association of the door with the structure of the oven during assembly. Another object of the present invention is to provide a hinge for doors

of ovens or the like which can be manufactured with known low-cost equipment.

This aim and these and other objects, which will become better apparent hereinafter, are achieved by a hinge for doors of ovens or the like, of the type which comprises:

- a first elongated arm, to be fixed to the structure of the door of the oven;

- a second arm, which is pivoted to said first arm and is designed to be fixed to the structure of the oven; - a mechanism which is adapted to manage the relative angular position of said first arm on said second arm; characterized in that said second arm has an internal space which is open upward and in that said mechanism is constituted by:

- a slider which can perform a translational motion substantially in the longitudinal direction of said first arm by association with guiding means formed on said first arm;

- a linkage which is pivoted respectively to said second arm and to said slider, said linkage being arranged partly within said space formed in said second arm; - an intermediate body, which is pivoted to said slider on the same axis on which said linkage is pivoted to said slider, said intermediate body having a cam-like coupling with said second arm which is suitable to ensure a stable balance position of said first arm on said second arm which corresponds to the position in which the door is closed onto the chamber of the oven;

- elastic means, which are rigidly coupled to said first arm and act by traction on said intermediate body.

Brief description of the Drawings

Further characteristics and advantages of the invention will become better apparent from the following detailed description of a preferred but not

exclusive embodiment thereof, illustrated by way of non-limiting example in the accompanying drawings, wherein:

Figure 1 is a sectional side view of a hinge according to the invention applied to an oven, illustrating the open configuration of the door of the oven;

Figure 2 is an enlarged- scale view of a detail of the hinge of Figure 1 , with the door in the configuration for closure onto the oven;

Figure 3 is an exploded view of the hinge of the preceding figures;

Figure 4 is a perspective view of the hinge of the preceding figures, in an intermediate step of the opening action;

Figure 5 is a sectional side view of the hinge of the preceding figures in an intermediate step of the opening action, with a disk for locking the rotation of the two arms of the hinge associated therewith;

Figure 6 is a sectional side view of a hinge according to the invention in an intermediate step of the opening action, with a different embodiment of means for locking the relative rotation of the hinge arms;

Figure 7 is a sectional side view of part of the hinge of Figure 6 in the open configuration. Ways of carrying out the Invention It is noted that anything found to be already known during the patenting process is understood not to be claimed and to be the subject of a disclaimer.

With reference to the figures, a hinge for oven doors, according to the invention, is generally designated by the reference numeral 10. The structure of the oven is generally designated by the reference numeral 11, while the door of the oven is designated by the reference numeral 12.

The hinge 10 comprises a first elongated arm 13, to be fixed to the door 12 of the oven 11 (the oven and the door are shown schematically in broken lines), and a second arm 14, which is pivoted to the first arm 13, to

be fixed to the structure of the oven 11; pivoting between the first arm 13 and the second arm 14 occurs by means of a first pivot 15.

A mechanism is also interposed between the first arm 13 and the second arm 14, is generally designated by the reference numeral 16, and is adapted to manage the relative angular position of the first arm 13 on the second arm 14.

In particular, according to a known type of configuration, the first arm 13 has a substantially C-shaped transverse cross-section which is adapted to form a longitudinal receptacle 17 for the components of the mechanism 16. The second arm 14 is pivoted to the side walls 18 of the longitudinal receptacle 17 and is provided internally with a space 19 which is open upward.

In particular, the second arm 14 is constituted by two plates 20, which are symmetrical, correspondingly face each other, and are joined by a transverse bridge 21.

The plates 20 are formed monolithically, for example conveniently by blanking and U-shaped bending of a metallic lamina.

The contour of each plate 20 has an upper spur 22, which is suitable to be arranged for extraction-preventing abutment against the internal front wall 23 of a seat 24 provided in the structure of the oven 11, and a lower slot 25, which is suitable to accommodate a lower lip 26 of the seat 24.

The contour of each plate 19 also has a rear portion 27 at which the first arm 13 is pivoted.

The mechanism 16 comprises a slider 28, which can perform a translational motion substantially in the longitudinal direction of the first arm 13 by association with guiding means 29 provided on the first arm 13.

The slider 28 is constituted by a pivot, hereinafter referenced as second pivot 30, the ends of which are guided in parallel slots 31, which constitute the guiding means 29 and are formed symmetrically on the side walls 18 of the receptacle 17 provided in the first arm 13.

The mechanism 16 further comprises a plate-like linkage 32 which is pivoted respectively to the second arm 14 and to the slider 28.

The linkage 28 is arranged partly within the space 19 formed by the U-shaped bend of the second arm 14 and is pivoted to the second arm 14 by virtue of a third pivot, designated by the reference numeral 33, which is arranged so as to pass through the plates 20.

The pivoting axis of the linkage element 32 on the second arm 14 is spaced upward with respect to the pivoting axis of the first arm 13 on the second arm 14; the straight line, designated schematically by the reference letter A in Figure 2, which connects the centers of rotation of the linkage element 32 on the second arm 14 and of the first arm 13 on the second arm 14, is incident with respect to the interface surface between the door and the oven when the door is closed on the chamber of the oven.

Moreover, the mechanism 16 comprises an intermediate body 34, which is pivoted to the slider 28 on the same axis by means of which the linkage 32 is pivoted to the slider 28, in practice the axis of the second pivot 30 which constitutes the slider 28.

The intermediate body 34 is constituted by a U-shaped lamina, between the lateral wings 35 of which the slider 28 is arranged. The intermediate body 34 further has a cam-like coupling, designated by the reference numeral 36, with the second arm 14; the cam-like coupling 36 is suitable to ensure a position of stable balance of the first arm 13 on the second arm 14 which corresponds to the closed position of the door 12 on the chamber of the oven 11, as shown in Figure 2. The cam-like coupling 36 is constituted by a roller, generally designated by the reference numeral 37, which is arranged so that it can rotate between the lateral wings 35 of the intermediate body 34 and is arranged in sliding contact, during part of the relative rotation of the first arm 13 on the second arm 14, with a cusp-shaped portion 38 provided on the upper edge 35 of the second arm 14.

The arrangement of the roller 37 on the part of the cusp-shaped portion 38 which is directed toward the bottom of the receptacle 17 formed in the first arm 13, as shown in Figure 2, corresponds to the closed position of the door 12 on the chamber of the oven 11. Finally, the mechanism 16 comprises elastic means 39, which are rigidly coupled to the first arm 13 and act by traction on the intermediate body 34.

The elastic means 39 are constituted by a traction spring 40, which is rigidly coupled at its ends respectively to a first engagement portion 41 , such as a fourth pivot which lies transversely to the side walls 18 of the receptacle 17, and to a second engagement portion 42, such as a fifth pivot which is formed transversely between the wings 35 of the intermediate body 34.

The linkage 32 has, proximate to its axis of pivoting to the second arm 14, an extension tab 43 which is suitable to abut against a lower stroke limiting abutment 44 for the linkage 32 when the first arm 13 is turned in a position which corresponds to the fully open position of the door 12 with respect to the chamber of the oven 11 , as clearly shown in Figure 1.

The lower stroke limit abutment 44 is formed on the second arm 14 inside the space 29 formed by the U-shaped fold and is constituted for example by a sixth pivot 45, which is arranged so as to pass through at least one of the two plates 20.

When the tab 43 abuts against the lower stroke limit 44, the slider 28 is in abutment against the lower ends of the guiding slots 31. The operation of the hinge is as follows.

The first arm 13 and the second arm 14 are mutually pivoted, while the spring 40 pulls the linkage 32, in practice acting on the slider 28.

The fact that the pivoting axis of the linkage 32 on the second arm 14 is spaced upward with respect to the axis of pivoting of the first arm 13 to the second arm 14 in practice causes the spring to pull eccentrically on the

second arm 14, leading to a rotation of the first arm 13 on the second arm 14; the eccentric traction hypothetically ceases when the direction of traction of the spring is aligned with the straight line A that connects the centers of rotation of the linkage 32 on the second arm 14 and of the first arm 13 on the second arm 14.

Since the straight line A is incident to the surface that acts as interface between the door and the oven when the door is closed on the oven chamber, said alignment cannot occur; the first arm 13 turns until the door 12 abuts against the face of the chamber of the oven 11. In order to increase safety, when the door 12 abuts against the face of the chamber of the oven 11, the roller 37 is positioned on the part of the cusp-shaped portion 38 which is directed toward the bottom of the receptacle 17 formed on the first arm 13, as shown in Figure 2, increasing the stability of the closure position of the door. The door 12 opens simply by turning it downward; the mechanism 16 is structured so that the door 12, taking into account its center of gravity, is always balanced in any angular position comprised between the cusp-shaped portion 38 and the fully open position, which corresponds to the abutment of the tab 43 against the lower stroke limit abutment 44 and to the abutment of the slider 28 against the lower ends of the guiding slots 31.

Advantageously, the hinge 10 comprises means 46 for the angular locking of the rotation of the first arm 13 on the second arm 14 in an angular position which is suitable to allow the assembly of the second arm 14 to the structure of the oven 11 (Figure 5). This angular position corresponds to a rotational position which is intermediate between the position in which the door is closed onto the chamber of the oven (as in Figure 2) and a position which corresponds to the maximum opening of the door (Figure 1).

The angular locking means 46 comprise a locking element 47 (shown in broken lines in Figure 5), which is suitable to be interposed under

compression, due to an indirect effect of the thrust of the elastic means 39, between a first abutment 48, formed on the first arm 13, and a second abutment 49, which lies inside the space 19 formed by the U-shaped bending of the second arm 14. In particular, the locking element 47 is constituted by a disk which can be inserted partially within the slot 50 for the upward opening of the space 19 formed by the U-shaped fold of the second arm 14; in the sectional figures, the slot 50 is shown with reference to its longitudinal edge.

The disc is inserted in the slot 50 by abutting laterally both against the first abutment 48, which corresponds to the base of the cutout 51 formed at the end of the first arm 13, in order to allow the exit of the front portion of the second arm 14 from the receptacle 17 of the first arm 13, and on the second abutment 49, constituted by a tab 52 which is monolithic with the edge of one of the two plates 20 and is folded at right angles thereto. Further, said disk which constitutes the locking element 47 abuts against a lower support 53 which is formed within the space 19 and constitutes the upper part of the six pivot which provides the lower stroke limit 42.

The disk, which can be conveniently a coin of appropriate diameter, can therefore be inserted and removed easily from the slot 50.

A different embodiment of angular locking means, shown in Figures 6 and 7 and designated by the reference numeral 146, comprises a locking element 147, which is adapted to be interposed under compression, by indirect effect of the thrust of the elastic means 139, between a first abutment 148 formed on the first arm 13 and a second abutment 149 formed inside the space 19 formed by the U-shaped fold of the second arm 14.

In this embodiment, the locking element 147 is constituted by a lever 154, which is pivoted to the second arm 14 and partly contained within the slot 150 for upward opening of the space 19 formed by the U-shaped fold of the second arm 14.

The end 155 of the lever which lies opposite the end for pivoting to the second arm 14 abuts, during the locking step, against the first abutment 148.

In particular, the second abutment 149 is constituted by the pivot for the pivoting of the lever 154, while the first abutment 148 is constituted by the base of the cutout 51 formed at the end of the first arm 13 in order to allow the protrusion of the front portion of the second arm 14 from the receptacle 17 of the first arm 13.

The end 154 of the lever 153 is wider than the width of the slot 50, for example by way of a transverse folding of the end 154, in order to avoid complete insertion of the lever in the slot 50.

Figure 7 illustrates the position of the lever once the hinge has been associated with the oven 11.

In practice it has been found that the invention thus described solves the problems described above in known types of hinge for ovens.

In particular, the present invention provides a hinge for doors of ovens or the like which is simplified with respect to known types of hinge, since the number of components is reduced to a minimum.

The shape of the components also is simple and said components are substantially all obtainable by blanking and bending metallic plates.

Further, the use of locking means for angular locking of the relative rotation of the two arms of an extremely simple type, such as for example a coin, allows to simplify considerably the step of associating said hinge with the oven. The variation of said angular locking means which has the lever reprises a per se known concept; the application of the individual lever accommodated between the plates that form the second arm is constructively simple and leads to smaller overall dimensions.

The invention thus conceived is susceptible of numerous modifications and variations, all of which are within the scope of the

appended claims; all the details may further be replaced with other technically equivalent elements.

In practice, the materials employed, so long as they are compatible with the specific use, as well as the dimensions, may be any according to requirements and to the state of the art.

The disclosures in Italian Patent Application No. PD2006A000034 from which this application claims priority are incorporated herein by reference.

Where technical features mentioned in any claim are followed by reference signs, those reference signs have been included for the sole purpose of increasing the intelligibility of the claims and accordingly such reference signs do not have any limiting effect on the interpretation of each element identified by way of example by such reference signs.