Abstract:
A hinge for doors of domestic appliances such as ovens or the like, comprises a first member fixable to a frame of the domestic appliance, a second hinge member fixable to a door and kinematic connection means between the first and the second hinge member to make them tiltably movable relative to each other so that the door can move relative to the frame between a closed position and at least one open position.

Description:
[0001]    This application claims priority to Italian Patent Application BO2013A000663 filed Nov. 29, 2013, the entirety of which is incorporated by reference herein. 
       BACKGROUND OF THE INVENTION 
       [0002]    This invention relates to a hinge for doors of domestic appliances. 
         [0003]    More specifically, this invention relates to a hinge for connecting the door of a domestic appliance to the respective mounting frame. 
         [0004]    This specification describes the present invention with reference to an oven purely by way of a non-limiting example. 
         [0005]    The doors of domestic appliances, especially those of ovens, are often subjected to improper use, at times decidedly dangerous. 
         [0006]    In effect, when open, an oven door makes a horizontal surface which a user might incorrectly consider to be a convenient supporting surface. 
         [0007]    Especially in the case of ovens mounted near the floor, it is not unlikely for this “supporting surface” to be used in an extremely dangerous manner, even like a step to gain access to high kitchen shelves. 
         [0008]    Under such extreme circumstances, given a person&#39;s average weight and the lever arm on which this weight force is applied, the oven will very likely topple over, with unpleasant consequences which are not difficult to imagine. 
         [0009]    To avoid dangerous events of this kind, the applicant of this invention previously developed a hinge for domestic appliances which was capable of angular extra-travel through more than 90°, so that the oven door could be inclined when a weight force with a mainly vertical component was applied to it. 
         [0010]    This and other prior art solutions, although satisfactory in many respects have not proved to be free of disadvantages. 
         [0011]    The main disadvantages of the prior art hinges of this kind are due to their constructional complexity and to component wear. 
       SUMMARY OF THE INVENTION 
       [0012]    This invention therefore has for an aim to provide a hinge for domestic appliance doors which is capable of extra-travel beyond the normal door open position and which is free of the disadvantages of prior art hinges. 
         [0013]    Another aim of the invention is to provide a hinge that is simple and economical to make and practical and functional to use. 
         [0014]    The technical features of the invention, with reference to the above aims, can be easily inferred from the appended claims, in particular claim  1 , and preferably any of the claims that depend, either directly or indirectly, on claim  1 . 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0015]    The advantages of the invention are more apparent from the detailed description which follows, with reference to the accompanying drawings which illustrate preferred non-limiting embodiments of it purely by way of example, and in which: 
           [0016]      FIG. 1  is a schematic perspective view from above of an oven with a door connected to it by two hinges made in accordance with the present invention; 
           [0017]      FIGS. 2 to 5  are schematic side elevation views, with some parts transparent, showing a first embodiment of the hinge according to the invention in four different use configurations; 
           [0018]      FIGS. 6 to 9  are schematic side elevation views, with some parts transparent, showing a second embodiment of the hinge according to the invention in four different use configurations; 
           [0019]      FIGS. 10 to 13  are schematic side elevation views, with some parts transparent, showing a third embodiment of the hinge according to the invention in four different use configurations. 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0020]    The numeral  1  in  FIG. 1  denotes in its entirety an oven comprising a frame  2  to which a door  3  is connected by two hinges  100 ,  200 ,  300 , illustrated schematically, which enable it to be tiltably rotated about a first, horizontal axis A. 
         [0021]      FIGS. 2 to 5  illustrate a first embodiment of the hinge according o this invention, denoted by the reference numeral  100 . 
         [0022]    Each of the two hinges  100  comprises a first member  4  fixed to the frame  2  of the oven  1  a second member  5  fixed to the door  3  and a first spring  6  designed to balance the tilt opening movement of the second hinge member  5  relative to the first hinge member  4 . 
         [0023]    With reference to  FIGS. 2 to 5 , the hinge  100  comprises a first rocker lever  7  pivoted to the first hinge member  4  to rock relative to it about a respective first pivoting axis B perpendicular to the placement plane of the drawings. 
         [0024]    The first rocker lever  7  has, on opposite sides of the first pivoting axis B, a first end  7   a  and a second end  7   b.    
         [0025]    At its first end  7   a  the first rocker lever  7  has a first cam profile  8 . 
         [0026]    The first profile  8  has two concave zones separated by a convex portion  8   b.    
         [0027]    The first cam profile  8  terminates, at one end of it, with a hook-shaped portion  8   a  incorporating one of the two concave zones. 
         [0028]    At its second end  7   b  the first rocker lever  7  has an element  9  for engaging a top end of the first spring  6 . 
         [0029]    At its bottom end, the first spring  6  is connected to the first hinge member  4 . 
         [0030]    As illustrated in  FIGS. 2 to 5 , the hinge  100  comprises a follower element  10  designed to engage the first cam profile  8 . 
         [0031]    More specifically, as explained in more detail below, the follower element  10  engages the first cam profile  8  when the door has nearly reached its open position, as illustrated in  FIGS. 4 and 5 . 
         [0032]    The follower element  10  comprises a rod  11  pivoted to the first hinge member  4  to rock relative to it about a second pivoting axis C and a roller  12  designed to abuttedly engage the first cam profile  8 . 
         [0033]    The roller  12  is rotatably mounted on the rod  11  at a first end  11   a  thereof. 
         [0034]    The hinge  100  comprises a second spring  13  which opposes the rocking movement of the follower element  10 . 
         [0035]    The second spring  13  has two longitudinally opposite ends, one of which is connected to the rod  11  of the follower element  10  and the other is connected to the first hinge member  4 . 
         [0036]    With reference to  FIGS. 2 to 5 , the hinge  100  also comprises a control lever  14  for controlling the first rocker lever  7 . 
         [0037]    The control lever  14  is pivoted by its longitudinal ends  14   a,    14   b  to the first rocker lever  7  and to the second hinge member  5 , respectively. 
         [0038]    The control lever  14  has a second cam profile  15  which is also designed to engage the follower element  10 . 
         [0039]    More specifically, as explained in more detail below, the second cam profile  15  engages the follower element  10  when the door has nearly reached its closed position, as illustrated in  FIG. 2 . 
         [0040]    The above mentioned first rocker lever  7 , follower element  10 , control lever  14  and first spring  6  define, in their entirety for the hinge  100 , respective kinematic connection means  21  between the first hinge member  4  and the second hinge member  5 . 
         [0041]    In use, in the configuration illustrated in  FIG. 2 , where the door  3 , not illustrated, is in a closed position relative to the frame  2 , also not illustrated, the follower element  10  is engaged with the second cam profile  15  of the control lever  14 . 
         [0042]    The follower element  10 , thanks to the spring  13 , applies to the control lever  14 , and through the latter to the second hinge member  5 , the closing force necessary to keep the door  3  firmly in the closed position. 
         [0043]      FIG. 3  illustrates the hinge  100  in the configuration of it which defines an intermediate open position of the door  3 . In this intermediate configuration the follower element  10  is not engaged either with the first cam profile  8  or with the second cam profile  15 . 
         [0044]      FIG. 4  illustrates the hinge  100  in the configuration of it which defines a fully open position of the door  3 , in this fully open configuration the follower element  10  is engaged with the first cam profile  8 . 
         [0045]    More precisely, the roller  12  engages a concave zone of the first cam profile  8 . 
         [0046]    It is a condition of equilibrium where the weight of the door  3 , not illustrated, pushes the first end  7   a  of the first lever  7  against the follower element  10  and applies to the latter a force which is schematically represented by an arrow F in the drawing. In this configuration, the second spring  13  is advantageously loaded and applies an opposing action. 
         [0047]      FIG. 5  illustrates the hinge  100  in the configuration of it which defines an extra open position of the door  3 . This configuration is adopted by the hinge  100  when a certain force F 1  is applied to the door. 
         [0048]    The extent of the force F 1 , depends on numerous factors, such as, in particular, the weight of the door  3  and the characteristics of the springs  6  and  13 . For the purposes of this specification, however, it is sufficient to provide an indication of the nature of the force F 1 , that is to say, a force which, if applied to a flat inside surface of the door  3  in the open position, can cause the oven to topple. For precautionary reasons, the value set for the force F 1  is well below that which will actually cause the oven to topple. 
         [0049]    The above mentioned force F 1  represents the effect of resting a mass on the flat inside surface  3   a  of the door  3 . By “mass” is meant any object capable of applying a respective weight force on the door  3 , even the body of a user erroneously stepping onto or attempting to step onto the door  3 . 
         [0050]    The action of the force F 1  on the hinge  100  causes the door  3  to adopt the extra open position, corresponding to a respective extra open configuration of the second body  5 , illustrated in  FIG. 5 . 
         [0051]    Between the closed configuration of the second body  5 , illustrated in  FIG. 2  and corresponding to the closed position of the door  3 , and its extra open configuration, illustrated in  FIG. 5 , there is an angle a greater than 90°. 
         [0052]    Thanks to the extra open position of the door  3 , any mass bearing down on the door  3  is made to slide off, thus eliminating the cause which would lead to the risk of the oven toppling. 
         [0053]    Advantageously, the roller  12  of the follower element  10  is in contact with the cam profiles  8 ,  15  only during certain stages of the open-close cycle of the door  3 , thus limiting the wear due precisely to contact between the roller  12  and the cam profiles  8  and  15   
         [0054]    More in detail, application of the force F 1  pushes the first end  7   a  of the first lever  7  against the follower element  10  and applies to the latter a force which is schematically represented by an arrow F′ in  FIG. 5 . The force F′ causes the roller  12  to overcome the obstacle constituted by the convex portion  8   b  of the cam profile  8  and to come into abutment against and engage the hook-shaped portion  8   a.    
         [0055]      FIGS. 6 to 9  illustrate a second embodiment of the hinge according to this invention, denoted by the reference numeral  200 . 
         [0056]    The components of the hinge  200  already mentioned in the description of the hinge  100  are denoted by the same reference numerals in the following description, too. 
         [0057]    Like the first embodiment  100  described above, the hinge  200  comprises a first member  4  fixed to the frame  2  of the oven  1 , a second member  5  fixed to the door  3  and a first spring  6  designed to balance the tilt opening movement of the second hinge member  5  relative to the first hinge member  4 . 
         [0058]    With reference to  FIGS. 6 to 9 , the hinge  200  comprises a first rocker lever  7  pivoted to the first hinge member  4  to rock relative to it about a respective first pivoting axis B perpendicular to the placement plane of the drawings. 
         [0059]    The first rocker lever  7  has, on opposite sides of the first pivoting axis B, a first end  7   a  and a second end  7   b.    
         [0060]    At its first end  7   a  the first rocker lever  7  has a first cam profile  8 . 
         [0061]    The first cam profile  8  terminates at one end of it, with a hook-shaped portion  8   a.    
         [0062]    At its second end  7   b  the first rocker lever  7  has an element for engaging a top end of the first spring  6 . 
         [0063]    At its bottom end, the first spring  6  is connected to the first hinge member  4 . 
         [0064]    As illustrated in  FIGS. 6 to 9 , the hinge  200  comprises a follower element  10  designed to engage the first cam profile  8 . 
         [0065]    More specifically, as explained in more detail below, the follower element  10  engages the first cam profile  8  when the door has nearly reached its open position, as illustrated in  FIGS. 8 and 9 . 
         [0066]    The follower element  10  comprises a rod  11  pivoted to the first hinge member  4  to rock relative to it about a second pivoting axis C and a roller  12  designed to abuttedly engage the first cam profile  8 . 
         [0067]    The roller  12  is rotatably mounted on the rod  11  at one end  11   a  thereof. 
         [0068]    The hinge  200  comprises a second spring  13  which opposes the rocking movement of the follower element. 
         [0069]    The second spring  13  has two longitudinally opposite ends, one of which is connected to the rod  11  and the other is connected to the first hinge member  4 . 
         [0070]    With reference to  FIGS. 6 to 9 , the hinge  200  also comprises a control lever  14  for controlling the first rocker lever  7 . 
         [0071]    The control lever  14  is pivoted by its longitudinal ends  14   a,    14   b  to the first rocker lever  7  and to the second hinge member  5 , respectively. 
         [0072]    The control lever  14  has a second cam profile  15  which is s designed to engage the follower element  10 . 
         [0073]    More specifically, as explained in more detail below, the second cam profile  15  engages the follower element  10  when the door has nearly reached its closed position, as illustrated in  FIG. 6 . 
         [0074]    The hinge  200  also comprises a second rocker lever  16 . 
         [0075]    The second rocker lever  16  is pivoted to the first hinge member  4  to rock relative to it about a respective third pivoting axis D perpendicular to the placement plane of the drawings. 
         [0076]    The second rocker lever  16  has, on opposite sides of the third pivoting axis D, a first end  16   a  and a second end  16   b.    
         [0077]    At its first end  16   a  the second rocker ever  7  is pivoted to the second hinge member  5  attached to the door  3 . 
         [0078]    At its second end  16   b  the second rocker lever  16  rotatably supports a roller  17 . 
         [0079]    The roller  17 , as a follower element, is designed to engage a slot  18  made in the control lever  14  and defining a third cam profile  19 . 
         [0080]    The above mentioned second hinge member  5 , first rocker lever  7 , second rocker lever  16  and control lever  14  together form an articulated mechanism for controlling the opening and closing movement of the door  3 . 
         [0081]    In this articulated mechanism, the third cam profile  19  and the follower constituted by the roller  17  constitute means  20  for guiding the relative movement between the second rocker lever  16  and the control lever  14 . 
         [0082]    The above mentioned first rocker lever  7 , second rocker lever  16 , follower element  10 , control lever  14  and first spring  6  define, in their entirety for the hinge  200 , respective kinematic connection means  21  between the first hinge member  4  and the second hinge member  5 . 
         [0083]    The operation of the hinge  200  illustrated in  FIGS. 6 to 9  is very much the same as that described above with reference to the hinge  100  and, for the sake of brevity, the reader is referred thereto. 
         [0084]      FIGS. 10 to 13  illustrate a third embodiment of the hinge according to this invention, denoted by the reference numeral  300 . 
         [0085]    The hinge  300  substantially comprises all the components of the hinge  200  which have already been mentioned in the respective description which the reader is referred to for brevity. 
         [0086]    In addition to the components which are equivalent to those of the hinge  200 , the hinge  300  comprises a damping element  22  designed to apply to the first rocker lever  7 , and indirectly to the second hinge member  5  attached to the door  3 , a damping action on the reciprocating motion of the first and second hinge members  4  and  5  when near to the closed position. 
         [0087]    In the preferred but non-limiting embodiment of the hinge  300  illustrated in  FIGS. 10 to 13 , the damping element  22  comprises a gas or fluid cylinder  23  equipped with a linearly movable rod  24 . 
         [0088]    The damping element  22  also comprises an engagement portion  25  integral with the rod  24  against which portion  25  the first end  7   a  of the first rocker lever  7  is designed to abuttedly engage during the rocking movement of the first lever  7  about its first axis B. 
         [0089]    With the exception of the aspects regarding the damping element  22 , the operation of the hinge  300  illustrated in  FIGS. 10 to 13  is very much the same as that described above with reference to the hinge  100  and, for the sake of brevity, the reader is referred thereto. 
         [0090]    As clearly illustrated in  FIGS. 10 to 13 , which represent different configurations of the hinge  300  corresponding to the different stages in the movement of the door  3  from its extra open position, shown in  FIG. 10 , to its closed position, shown in  FIG. 13 , the first lever  7  engages the damping element  22  when near the closed position, thus causing its cylinder  23  to be compressed. 
         [0091]    In other words, in use, when the door  3  reaches an intermediate closed position, where contact is made with the above mentioned first end  7   a  of the first rocker lever  7 , the damping element  22 , following compression of the cylinder  23 , applies a damping action opposing the closing action applied by the first spring  6 , thereby slowing the movement of the door  3  towards its fully closed position.