Patent Publication Number: US-8533914-B2

Title: Hinge for wings or doors

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to a hinge for wings or doors, and in particular to a hinge designed to connect doors of electrical appliances, such as ovens, to the respective supporting frame. 
     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 normally consist of two separate parts, kinematically connected to one another, directly or by inserting a lever or the like between them. 
     In known types of ovens hinges usually comprise two separate elements, kinematically connected to one another and both having a box-shaped structure. More precisely, one of the two box-shaped structures is fixed to the oven frame, at one side of the oven mouth, whilst the other box-shaped structure is fixed to one edge of the door, which in that way is rendered movable with a tilting action relative to the above-mentioned frame. 
     Between the two box-shaped structures a lever element is operatively inserted as a connecting element, the lever element pivoting on one of the two box-shaped structures, usually on the one stably fixed to the door, and having a first arm rigidly connected to the other of the two box-shaped structures. The second arm of the lever element, coplanar with the first, is operated on by elastic elements which influence the movement of the door, for both opening and closing. 
     During door rotation starting from the closed position, the elastic elements oppose, during a first step, the detachment of the door from the oven supporting frame and, in a second step, subsequent rotation of the door and its consequent lowering to an end of stroke position in which the oven mouth is completely open. In this second opening step, the door, under the combined action of its own weight which promotes its descent and of the elastic elements which apply a braking action, performs a gradual rotation. 
     During door rotation starting from its open end of stroke position, the action of the elastic elements is first balanced by the weight of the door, initially guaranteeing gradual closing rotation; however, then, in the absence of a suitable braking action by the user, the elastic elements push the door towards the oven frame with such a force that it often closes in a rather sudden and noisy way. 
     SUMMARY OF THE INVENTION 
     The present invention has for an aim to provide a hinge for wings or doors which is free of the above-mentioned disadvantage and which at the same time has a simple structure and practical and effective operation. 
     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 . 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The advantages of the present invention are more apparent in the detailed description which follows, with reference to the accompanying drawings which illustrate preferred, non-limiting embodiments of the invention, in which: 
         FIG. 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; 
         FIGS. 2 to 4  are respective side elevation views with some parts in cross-section and others transparent, of a first embodiment of the hinge for wings or doors in accordance with the present invention, in its three different operating steps; 
         FIGS. 5 to 7  are respective side elevation views with some parts in cross-section and others transparent, of a second embodiment of the hinge for wings or doors in accordance with the present invention, in its three different operating steps; 
         FIGS. 8 to 10  are respective side elevation views with some parts in cross-section and others transparent, of a third embodiment of the hinge for wings or doors in accordance with the present invention, in its three different operating steps. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     With reference to  FIG. 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 horizontal axis A. 
       FIGS. 2 to 4  illustrate a first embodiment of a hinge  4  made in accordance with the present invention. 
     Each of the two hinges  4  comprises a first box-shaped body  5 , fixed to the oven  1  frame  2  at a respective side of the oven mouth, and a second box-shaped body  6 , fixed to a respective edge of the door  3 . 
     Both of the box-shaped bodies  5  and  6  have an extended shape and they are kinematically connected to one another by a connecting element  7 , which is also part of the hinge  4 . The connecting element  7  pivots on the second box-shaped body  6  by means of a pin  8  and has a portion  7   a  rigidly connected to the first body  5  to render the door  3  movable with a tilting action relative to the frame  2  between a closed limit position, illustrated in  FIG. 4 , and an open limit position, not illustrated. For a better understanding of the invention, illustrations of door  3  and hinge  4  partially open positions are useful, for example the configurations illustrated in  FIGS. 2 and 3 . 
     The hinge  4  also comprises a helical spring  9  fitted on the outside of the second box-shaped body  6 . The lower end coil  9   a  of the spring  9  is in contact with a transversal wall  10  of the second box-shaped body  6 . 
     The spring  9  is held in contact with said transversal wall  10  by the head  11  of a bar  12  positioned coaxially inside the spring  9  and which forms a guide for the spring  9 . 
     One end  12   a  of the bar  12  exits the bottom of the spring  9  and passes through an opening made in the transversal wall  10  and hooks onto a first longitudinal end  13   a  of a tension rod  13 , whose second longitudinal end  13   b  is hinged to the connecting element  7  by a pin  14  positioned close to the above-mentioned pin  8 . 
     The position of the pin  14 , where the elastic reaction force of the spring  9  is applied, relative to the pin  8 , and the pre-compression of the spring  9 , guarantee an elastic action which tends to continuously push and hold the door  3  in its closed position. 
     As illustrated in  FIGS. 2 to 4 , the hinge  4  comprises a gas or fluid damper cylinder  15  supported by a respective supporting plate  16  fixed cantilever-style on the first box-shaped body  5 . 
     In the particular, non-limiting embodiment illustrated in  FIGS. 2 to 4 , the cylinder  15  comprises a fixed rod  17 , integral with the plate  16 , and a body  18  which can move relative to the rod  17 . 
     Irrespective of whether it is of the type using gas or fluid, the damper cylinder  15  forms for the hinge  4  respective damping means  19  which, as explained in more detail below, are designed to apply on the second box-shaped body  6  an action damping its movement towards the first box-shaped body  5 , as the door  3  passes from an open position to the above-mentioned closed position. 
     The hinge  4  also comprises a rocker lever  20 , pivoting on the first box-shaped body  5  by means of a relative pin  21 , so that it can rotate about its own pivoting axis B, perpendicular to the plane of  FIGS. 2 to 4 . 
     On opposite sides of the pin  21 , the lever  20  has a first and a second arm, respectively labeled  20   a  and  20   b.    
     The first arm  20   a  of the lever  20  is designed to engage with the damper cylinder  15 , to press the movable body  18  against the rod  17 . 
     The lever  20  forms, for the hinge  4 , respective means  22  for operating the damping means  19 . 
     As illustrated in  FIGS. 2 to 4 , close to its upper zone  6   a , the second box-shaped body  6  has a projecting peg  23 , extending towards the first box-shaped body  5 . 
     The projecting peg  23  constitutes a control element  24  for the rocker lever  20 . As described in more detail below, the element  24  is designed to engage with the second arm  20   b  of the lever  20  to make the lever rotate about its pivoting axis B. 
     The following is a brief description of the operation of one of the hinges  4  illustrated in  FIGS. 2 to 4 , starting from a door  3  open position. 
     Starting from the door  3  fully open position, not illustrated, a rotation of the door and of the second box-shaped body  6  about the axis A towards the closed position is promoted by the elastic action of the spring  9  and is initially hindered by the weight of the door  3 . 
     With the second box-shaped body  6  in the position illustrated in  FIG. 2 , the elastic reaction force of the spring  9 , overcoming the weight, should push the door  3  to close quickly, the door in the meantime having reached a predetermined speed. 
     Operation of the spring  9 , compressed by the movement of the second box-shaped body  6  due to the pulling action applied by the tension rod  13  and by the bar  12  connected to it, is substantially known and therefore is not described in detail in this text. 
     As the door  3  closing movement continues, the second box-shaped body  6  of the hinge  4  reaches the position illustrated in  FIG. 3 , where the projecting peg  23  constituting the control element  24  makes contact with the second arm  20   b  of the rocker lever  20 . 
     As the door  3  passes between the still partly open position illustrated in  FIG. 3  and the closed position shown in  FIG. 4 , the damping means  19 , following damper cylinder  15  compression, apply a damping action conflicting with the closing action applied by the spring  9 , therefore making door  3  movement towards the fully closed position gradual and subject to a braking action. 
     In detail, with reference to  FIGS. 3 and 4 , the projecting peg  23 , integral with the second box-shaped body  6 , pushing the second arm  20   b  of the lever  20 , causes the lever  20  to rotate anti-clockwise about its pivoting axis B. Said rotation of the lever  20  results in its first arm  20   a  in turn pushing the movable body  15  against the fixed rod  17 , compressing the damper cylinder  15 . 
     It is therefore evident that, even in the absence of a braking action by the user, the door  3 , pushed towards the oven  1  frame  2  by the spring  9 , reaches the frame in a gentle, silent way thanks to the end of stroke damping provided by the damping means  19 . 
       FIGS. 5 to 7  illustrate a second embodiment of a hinge  4  made in accordance with the present invention. 
     In terms of the structural parts of which the hinge  4  in  FIGS. 5 to 7  consists, it differs from the hinge described above and illustrated in  FIGS. 2 to 4  only in the different shape of the means  22  for operating the damping means  19 , the relative control element  24  and the different positioning of the damper cylinder  15 . 
     In detail, with reference to  FIGS. 5 to 7 , in its second embodiment illustrated, the hinge  4  comprises a rocker lever  20 ′, pivoting on the first box-shaped body  5  by means of a relative pin  21 , so that it can rotate about its own pivoting axis B. 
     In the assembled hinge  4 , the rocker lever  20 ′ is positioned close to the connecting element  7  between the two box-shaped bodies  5 ,  6 . 
     On opposite sides of the pin  21 , the lever  20 ′ has a first and a second arm, respectively labeled  20 ′ a  and  20 ′ b.    
     The first arm  20 ′ a  of the lever  20 ′ is designed to engage with the damper cylinder  15 , to press the movable body  18  against the rod  17 . 
     The lever  20 ′ forms, for the hinge  4 , respective means  22  for operating the damping means  19 . 
     As illustrated in  FIG. 5 , the control element  24  consists of a wall  25  of the second box-shaped body  6  which is designed to engage, edgeways, with the second arm  20 ′ b  of the lever  20 . 
     Similarly to what is described above for the first embodiment of the hinge  4 , hereinafter there is a brief description of operation of the hinge  4  illustrated in  FIGS. 5 to 7 , starting from a door  3  open position. 
     Starting from the door  3  fully open position, not illustrated, a rotation of the door and of the second box-shaped body  6  about the axis A towards the closed position is promoted by the elastic action of the spring  9  and is initially hindered by the weight of the door  3 . 
     As the door  3  closing movement continues, the second box-shaped body  6  of the hinge  4  reaches the position illustrated in  FIG. 6 , where the wall  25  constituting the control element  24  makes contact with the second arm  20 ′ b  of the rocker lever  20 ′. 
     As the door  3  passes between the still partly open position illustrated in  FIG. 6  and the closed position shown in  FIG. 7 , the damping means  19 , following damper cylinder  15  compression, apply a damping action conflicting with the closing action applied by the spring  9 , therefore making door  3  movement towards the fully closed position gradual and subject to a braking action. 
     In detail, with reference to  FIGS. 6 and 7 , the wall  25  of the second box-shaped body  6 , pushing the second arm  20 ′ b  of the lever  20 , causes the lever  20  to rotate clockwise about its pivoting axis B. Said rotation of the lever  20 ′ results in its first arm  20 ′ a  in turn pushing the movable body  15  against the fixed rod  17 , compressing the damper cylinder  15 . 
     As already indicated relative to the first embodiment of the hinge  4 , again for the second embodiment illustrated in  FIGS. 5 to 7 , it is evident that, even in the absence of a braking action by the user, the door  3 , pushed by the spring  9  towards the oven  1  frame  2 , reaches the frame in a gentle, silent way thanks to the end of stroke damping provided by the damping means  19 . 
       FIGS. 8 to 10  illustrate a third embodiment of a hinge  4  made in accordance with the present invention. 
     In terms of the structural parts of which the hinge  4  in  FIGS. 8 to 10  consists, it differs from the hinge described above and illustrated in  FIGS. 2 to 4  only in the presence of a device  26  for moving the peg  23 , the device  26  being designed to move the peg  23  forward and backward depending on the different door  3  closing or opening steps. 
     The movement device  26  comprises a slide  27  integral with the tension rod  13 . The slide  27  comprises a cam profile  28  against which a peg  23  inner head  23   a  is designed to slidably engage. 
     The peg  23  slidably engages in a cylindrical bushing  29 , fixed to the second box-shaped body  6 , and a helical spring  30  is inserted between the bushing  29  and the head  23   a  of the peg  23  to apply an elastic force opposing movement of the head  23   a  towards the bushing  29 . 
     In practice, starting from the door  3  and second box-shaped body  6  fully open position, illustrated in  FIG. 8 , a rotation by both about the axis A towards the closed position is promoted by the elastic action of the spring  9  and is initially hindered by the weight of the door  3 . 
     With the second box-shaped body  6  in the position illustrated in  FIG. 8 , the peg  23  is in its first, back non-operating configuration. In other words, the peg  23  is practically housed inside the space delimited by the second box-shaped body  6 . 
     As the door  3  closing movement continues, with the rotation of the second box-shaped body  6  about its axis A, there is a relative movement between the tension rod  13  and the second box-shaped body  6 . Said relative movement causes the slide  27  to slide in the direction indicated by the arrow F in  FIG. 9 . 
     The movement of the slide  27 , as a result of contact between the slide  27  cam profile  28  and the head  23   a  of the peg  23 , causes the peg  23  to move in the direction of its own axis C, until it exits the second box-shaped body  6 , as illustrated in  FIGS. 9 and 10 . 
     As illustrated in  FIG. 10 , during the door  3  closing step, the peg  23  stably adopts its second, forward operating configuration in which, acting as the control element  24 , it can engage with and push the rocker lever  20 , similarly to what was described above with reference to the hinge  4  illustrated in  FIGS. 2  to  4 . 
     In its movement between the first, back configuration and the second, forward configuration, the peg  23  slides inside the bushing  29  and is opposed by the opposing action of the spring  30 . 
     When the door  3  is opened, that is to say, when passing between the second, forward configuration and the first, back configuration, the spring  30  pushes the peg  23  back into the second box-shaped body  6 . 
     Relative to all three embodiments of the hinge  4  described above, it must also be emphasized that the damping means  19  are supported by the first box-shaped body  5  and therefore are housed embedded in the electrical appliance frame  2 , in a position that is hidden from view and which is protected from knocks or dirt, with obvious advantages in terms of appearance and reliable operation. 
     Moreover, advantageously, thanks to their position in the frame  2  of the electrical appliance, when this is an oven, the damping means  19  are also better protected from heat than they would be if they were contained in the door  3 . 
     Protection from the heat of the oven allows the life of the damping means  19  to be extended. If they were not protected in this way, their shock absorbing capacity would deteriorate rapidly. 
     The control element  24  was described and illustrated as a peg or a wall of the box-shaped body, but it shall be understood that such embodiments are provided by way of example only and are non-limiting, since it could be made in any shape and size. 
     According to alternative embodiments of the present invention, not illustrated, there are elements for limiting friction, such as rollers or wheels, inserted between the control element and the rocker lever forming the means for operating the damping means.