Abstract:
An opening device including an elongate ejector ram mounted in a longitudinally displaceable manner in a housing and pretensioned at one end by a spring into a position in which it protrudes out of the housing and pushable back into the housing counter to the pretensioning. A releasable locking device locks the ejector ram in a position retracted in the housing. A tensioning device is provided forcibly displaces the ejector ram. When the movable furniture part is completely opened, a tensioning device forcibly displaces the ejector ram into the locking position retracted within the housing. The tensioning device converts the opening movement of the movable furniture part in the interior of the housing via a tensioning member having one end guided out of the housing into a movement pulling the ejector ram back into the retracted position.

Description:
This application is a 371 application of PCT/EP2007/006269 filed Jul. 14, 2007, which claims priority to the German application 20 2006 013 028.4 filed Aug. 24, 2006 and German Application 20 2007 005 782.2 filed Apr. 21, 2007. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The invention relates to an opening device for furniture parts which are movable relative to one another such as door leaves, flaps and the like which are pivotably articulated on a furniture carcass with an elongate ejector ram which is mounted so as to be longitudinally movable in or on a housing which can be fixed on one of the furniture parts which are movable relative to one another, wherein the ejector ram is biased by a spring with one end thereof into a position projecting out of the housing in the direction of the respective other furniture part and can be forced back against the spring bias into the interior of the housing, a locking device being provided which locks the ejector ram in the position in which it is retracted into the housing and can be unlocked by manipulation by a user. 
     2. Description of Related Art 
     For door leaves, flaps and the like which are articulated on the carcass of cabinets, closure fittings—for example catches—have been developed which are not only to be installed separately on the carcass or the door leaf but also integrated into the hinges which enable the pivot movement, and during the operation of closing a door leaf as it approaches the closed position these closure fittings pull the door leaf resiliently into the closed position and also retain it in the closed position. In order in this case to avoid or to reduce impact noises and vibrations of the piece of furniture, damping devices for the concluding closing operation of the door leaves have been developed recently which can also be mounted separately on the carcass or on the door leaf or can be integrated into the hinges. 
     In an attempt to avoid, for visual/aesthetic reasons, the handle fittings which are necessary for opening and closing the door leaves or flaps, so-called touch-latch fittings have been developed which apart from a locking function for the closed door flap are provided with an additional opening function which makes it possible for the door leaf situated in the closed position to be unlocked by a pressure additionally exerted in the direction into the interior of the carcass and to be endowed with a movement in the direction of opening by an integrated spring arrangement, so that the door leaf lifts off from the cabinet carcass by a small angular amount and it is possible to grip the rear face of the door leaf in the edge region and to open the door leaf—even without the presence of a handle fitting. Also such touch-latch fittings can be constructed as separate fittings which can be installed in the region of the carcass aperture or as fittings integrated into the hinge (e.g. DE 20 2004 019 238.1). A problem then occurs when, in the case of a piece of furniture, as the pivotable furniture part approaches the closed position a closing function—which if possible is also damped—and in addition an opening function corresponding to the function of touch-latch fittings is to be implemented, because then the spring tensions which effect the respective closing or opening function act in the opposing direction. The kinematic design of the touch-latch devices also means that the door leaf in the closed position must still have a certain play for movement in the closing direction in order to be able to release the door leaf from the closed position before the opening function is initiated. The gap which is inevitably necessary as a result between the rear face of the door leaf and the end faces of the carcass walls is undesirable in many cases both for visual/aesthetic reasons and also for practical reasons. 
     SUMMARY OF THE INVENTION 
     The object of the invention therefore is to create an opening device for furniture parts pivotably articulated on a carcass which makes it possible for such a furniture part, for example a door leaf, which is closed completely, i.e. until its rear face abuts the end edges of a cabinet carcass, and is retained in the closed position by a spring-biased closure mechanism, to pivot automatically by a certain angular amount in the direction of opening without the attachment of handle fittings for the exertion of effective forces which act in the opening direction after actuation by the user. 
     Starting from an opening device of the type mentioned in the introduction, this object is achieved according to the invention in that in the housing a tensioning device is provided which moves the ejector ram forcibly into the locked position in which it is retracted into the housing when the movable furniture part is completely open, whereby by means of a tensioning element which with one end projecting out of the housing engages on the movable furniture part in the interior of the housing the tensioning device converts the opening movement of the movable furniture part into a retraction movement of the ejector ram into the retracted locked position. By the use of such an additional tensioning device which converts the predominant part of the opening movement of the pivotable furniture part into a displacement of the ejector ram over a relatively short distance, the movable furniture part can be moved during the closing operation into the completely closed position without the need at the end of the closing movement to overcome a resilient counterpressure, as is necessary in the known touch-latch fittings. Also there is no need for a gap between the movable furniture part, e.g. the rear face of a door leaf and the cabinet carcass, which is necessary for unlocking of touch-latch fittings from the closed position and provides the actuating path. 
     In a preferred embodiment of the invention the tensioning device has a two-armed lever component which is mounted in the housing so as to be pivotable about an axis at right angles to the longitudinal central axis of the ejector ram and of which one lever arm is in engaged connection in a free end region with the region of the ejector ram which is retained so as to be displaceable in the interior of the housing, whilst coupled to the end region of the other lever arm is an elongate rod component of which the free end which projects out of the housing wall facing the door leaf is provided with means for traction- and/or pressure-transmitting fixing on the inner face of the door leaf. 
     In this case the engaged connection of the first lever arm of the lever component to the ejector ram is advantageously constructed kinematically in such a way that the lever arm is coupled to the ejector ram so as to be pivotable and in addition displaceable by a predetermined amount parallel to the longitudinal axis of the ejector ram. 
     In this case the lever component is preferably formed by two parallel two-armed levers which are spaced from one another, wherein the clear distance between the lever arms of the two-armed lever on the ejector ram side is substantially the same as or only slightly greater than the external diameter of the ejector ram. 
     In this way the construction can be such that the engaged connection of the end regions of the lever arms of the lever on the ejector ram side has lugs which engage in each case in an associated longitudinal groove of predetermined length in the opposing outer face in the ejector ram. Thus this engaged connection constitutes, as it were, a simple crank/groove connection which produces the pivotable and longitudinally displaceable coupling of the lever component on the ejector ram. 
     In a preferred alternative embodiment of the invention the lever component is constructed so that in addition to its pivotable mounting it is displaceable in the vertical direction by a predetermined amount at right angles to the longitudinal central axis of the ejector ram in order that the component of motion at right angles to the longitudinal central axis of the ejector ram produced during the pivoting of the lever component can be compensated for by a displacement of the lever component in the opposite direction. 
     In this case the construction is then such that the pivot axis of the lever component is formed by two aligned lugs each projecting from the outer faces of the lever which face away from one another, the lugs projecting in each case into an associated groove which extends by the predetermined amount in the vertical direction in the inner surfaces of the opposing walls of the housing. 
     The rod component which transmits the opening movement of the door leaf to the lever component is then advantageously likewise coupled on the second lever arm so as to be pivotable and displaceable by a predetermined amount in the direction of the longitudinal central axis of the rod component. In a particularly simple manner this is possible due to the fact that in its end region within the housing the rod component has a loop-like elongate eye which is closed on both sides and through which passes a bolt which is retained in the end regions of the second lever arm of the lever of the lever component. 
     The other end of the rod component—which projects out of the housing—is then advantageously articulated on a fixing bracket which can be fixed on the inner face of the movable furniture part, i.e. the door leaf, so as to be pivotable about an axis extending at right angles and perpendicular to the longitudinal axis of the rod component. 
     The locking device, which locks the ejector ram in the retracted position in the housing and can be unlocked by manipulation by a user, advantageously has a pawl which is retained in the housing so as to be movable substantially at right angles to the direction of displacement of the ejector ram and can be brought into latching engagement on its end within the housing with a latching recess provided in the ejector ram, wherein the positioning of the latching recess in the ejector ram is such that in the retracted position of the ejector ram into the housing the pawl is aligned with the latching recess. In this case the pawl is preferably biased in resilient latching engagement with the latching recess. 
     The ejector ram can then be released from its retracted position in the housing by suitable means for remote release of the pawl from the latching engagement with the latching recess, so that due to the bias of the associated spring acting on the ejector ram this latter is guided into the position in which it projects out of the housing, thereby triggering the initial opening of the movement of the door leaf. The means for remote release of the pawl may be formed for example by actuating knobs connected to the pawl by way of cable pulls or coupling members or alternatively can be formed by pressure-sensitive actuating surfaces of electrical switches recessed in the door leaf or cabinet carcass. 
     In a modified embodiment of the opening device according to the invention the construction may also be such that a two-armed lever component with two lever arms pointing substantially in opposing directions is mounted so as to be pivotable in the housing, that the biased ejector ram is disposed in the end region of one lever arm and a latching component of the locking device locks the end of the lever arm in the pivoted position of the lever component associated with the retracted position of the ejector ram, and that the tensioning and stopping device is coupled to the end region of the other lever arm of the lever component. 
     In this case with regard to the smallest possible overall height of the opening device the construction is preferably such that the housing is dimensioned in the longitudinal direction of the pivot axis of the lever component so that the clear spacing between the substantially flat top walls of the housing which accommodate the lever component is approximately equal to the thickness of the lever component in the region of the pivot axis, wherein the top walls of the housing are at least partially closed along their edges on the ejector ram side by a low elongate side wall with a through opening for the ejector ram. In this case because of the small spacing between the top walls of the housing the possibility arises of mounting the housing on the inner face of the top wall or the base of the cabinet carcass. 
     The ejector ram then advantageously has the shape of a flat plate component which is displaceably guided between the inner faces of the top walls of the housing and has on the end wall side a flat pressure surface which in the retracted position of the ejector ram in the housing only projects slightly over the housing side wall in the through opening. 
     In an advantageous embodiment of the invention the latching component of the locking device is constructed as a pivot lever pivotably mounted between the top walls of the housing with a latching projection which is provided on its free end opposite the end on the pivot bearing side and which in the retracted locked positions engages under the end of the lever arm of the lever component associated with the ejector ram and thus fixes the lever component in the retracted locking position counter to the bias acting on it. 
     In this case it is advantageous if the pivot lever is coupled by gearing to a trigger unit which is disposed so as to be spaced from the pivot lever and has a thrust piece which is biased into a position projecting slightly over the side wall of the housing and of which the insertion movement produced when a pressure is exerted in the direction of the interior of the housing is converted by way of the geared coupling into a pivoting of the pivot lever for the purpose of a release of the locked end of the associated lever arm. 
     On the end of the pivot lever opposite the end on the pivot bearing side there is advantageously disposed an elongate tension/compression element of which the other end is connected to a lever arm of a pivotable toggle lever, the other lever arm of which is coupled to the thrust piece. 
     In an advantageous alternative embodiment the ejector ram is articulated on the associated lever arm of the lever component so as to be pivotable about an axis offset into the interior of the housing with respect to its pressure surface and—preferably—is disposed so as to be additionally displaceable by a predetermined amount substantially parallel to the pressure surface. 
     The ejector ram can have the shape of a flat body which is delimited so as to be flat on both sides in the regions opposite the top walls of the housing and of which the thickness measured between the opposing flat surfaces corresponds approximately to the clear spacing of the inner face of the top walls of the housing. 
     The tensioning and stopping device coupled to the locking device advantageously has a rod component as tensioning element coupled to the side of the movable furniture part inside the carcass on the one hand and to a flat slide mounted displaceably in the interior of the housing, wherein the slide is provided with a crank-like control groove which extends substantially in a straight line over the greater part of its length but which merges into a short end portion extending substantially at right angles to the straight region, and a control projection which is provided on a flat sector-shaped control disc pivotably disposed in the housing engages in the control groove and which in the closed position of the movable furniture part is located in the transversely extending end portion of the control groove and which, when the movable furniture part is opened, is moved into the straight portion of the control groove by the movement transmitted by the rod component to the slide as the control disc pivots, and thus enables the slide, which until then was retained by the engagement of the control projection in the control groove portion extending at right angles to the straight control groove portion, to move in the direction out of the interior of the carcass. 
     In an advantageous embodiment the rod component is coupled to the slide so as to be pivotable and displaceable to a predetermined extent in the direction of displacement of the slide. 
     When the opening device constructed in the manner according to the invention is disposed on a cabinet with a door leaf articulated pivotably on the cabinet carcass, the housing of the opening device is preferably disposed in the cabinet carcass with one of the housing top walls resting on the inner face of the upper top wall or—alternatively—of the base of the cabinet carcass in such a way that the pressure surface of the ejector ram, which in the retracted position projects only slightly from the side wall of the housing, rests substantially on the inner face of the door leaf which is in the closed position. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWING 
       In the following description the invention is explained in greater detail in connection with the drawings, in which: 
         FIG. 1  shows a side view of a portion of the supporting wall of a cabinet carcass on which a portion of a door leaf in the closed position is pivotably mounted by means of a hinge, wherein a first embodiment of an opening device according to the invention which is fixed on the supporting wall is shown schematically below the hinge; 
         FIG. 2  shows a side view in the direction of the arrows  2 - 2  in  FIG. 1 ; 
         FIG. 3  shows a view corresponding to  FIG. 1  in which the door leaf is shown in a position in which it is pivoted by approximately 10° in the opening direction relative to the closed position; 
         FIG. 4  shows a side view in the direction of the arrows  4 - 4  in  FIG. 3 ; 
         FIG. 5  shows a view corresponding to  FIGS. 1 and 3  in which the door leaf is shown in position in which it is pivoted by 90° in the opening direction relative to the closed position; 
         FIG. 6  shows a side view in the direction of the arrows  6 - 6  in  FIG. 5 ; 
         FIG. 7   a  shows the opening device illustrated schematically in  FIGS. 1 to 6  in an isometric representation in which its functional components are shown in the position corresponding to the closed position according to  FIGS. 1 and 2 ; 
         FIG. 7   b  shows a representation corresponding to  FIG. 7   a  in the closed position and without the housing; 
         FIG. 8   a  shows an isometric view of the opening device corresponding to  FIG. 7   a  in the partially opened position of its functional components corresponding to  FIGS. 3 and 4 ; 
         FIG. 8   b  shows a representation corresponding to  FIG. 8   a  in the closed position and without the housing; 
         FIG. 9   a  shows a view corresponding to  FIGS. 7   a  and  8   a  of the opening device in the open position of its functional components according to  FIGS. 5 and 6 ; 
         FIG. 9   b  shows a representation corresponding to  FIG. 9   a  in the open position and without the housing; 
         FIG. 10  shows an isometric view of the upper corner region of the side wall of a cabinet carcass, on which a door leaf illustrated in the partially open position is pivotably articulated, and of a second embodiment of an opening device constructed according to the invention which can be mounted on the inner face of the upper cabinet top wall (not shown); 
         FIG. 11  shows a top view opening device viewed in the direction of the arrow  11  in  FIG. 10 , wherein the door leaf is shown by dash-dot lines in the closed position and additionally in four further intermediate positions and the open positions; 
         FIG. 12  shows an exploded view of the opening device shown in  FIGS. 10 and 11  in an isometric representation; 
         FIGS. 13   a  to  13   f  show views in the direction of viewing according to  FIG. 11  but on an enlarged scale in which the functional parts of the opening device are each shown in the different positions of the door leaf shown schematically in  FIG. 11 ; and 
         FIGS. 14   a  to  14   f  each show views corresponding to  FIGS. 13   a  to  13   f  in the opposite viewing direction upwards from below. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     In  FIGS. 1 to 3  a portion of a door leaf  12  is shown which is articulated in a manner which is known per se so as to be pivotable on a side wall—denoted hereafter as a supporting wall  14 —of the carcass of a cabinet. The pivotable articulation of the door leaf  12  on the supporting wall  14  takes place by means of a conventional jointed hinge, of which only the hinge which pivotably couples the door leaf in the upper region to the supporting wall and is constructed as a four-bar hinge  16  is shown in the drawings, whilst the necessary second hinge which couples the said components in the lower region is not yet installed. The drawing shows in this region only the cut-out  18  on the door side as well as the fixing hole  20  for the hinge cup  22  and the fixing holes  24  for fixing the supporting wall mounting parts of the hinge constructed as an elongate supporting arm  26 . 
     An opening device denoted as a whole by  10  which is constructed in accordance with the invention and is fixed in the region of the supporting wall  14  on the door leaf side is shown schematically below the hinge  16 . 
     The opening device  10  described in greater detail below in connection with  FIGS. 7   a  to  9   b  has a housing  28  which is rectangular in the illustrated case, and the free end of an ejector ram  30  which is mounted so as to be longitudinally displaceable in the housing can project out of the housing wall on the door leaf side. Moreover, a rod component  33  which serves as a tensioning element also projects—below the ejector ram  30 —and the end of the rod component outside the housing is mounted so as to be pivotable in a fixing bracket  34  fixed on the inner face of the door leaf  12 . 
     The construction and the position of the functional components of the opening device  10  in different pivoted positions of the door leaf  12  relative to the supporting wall  10  is illustrated in  FIGS. 7   a  to  9   b.    
     The ejector ram  30  which is displaceably mounted in the housing  28  is biased into the position shown in  FIG. 8   a  in which it is pushed out of the housing  28  by a helical spring  32  which is under compression pretension and inserted between its end face within the housing and the opposing inner wall of the housing. In the region of the ejector ram directed towards the upper horizontal wall of the housing  28  there is provided a latching recess with which is associated a pawl  40  which passes displaceably through the housing wall and which in the position—shown in  FIGS. 7   a  and  9   a —in which it is retracted into the housing engages in the latching recess  38  and locks the ejector ram  30  against displacement into the extended position. If the pawl  40  is then raised by suitable manipulation and thus withdrawn from the latching recess  38 , the compression pretension of the spring  32  forces the ejector ram  30  out of the housing. In this case the door leaf  12  which is initially in the closed position shown in  FIGS. 1 and 2  is pivoted into the partially opened position shown in  FIGS. 3 and 4  in which the door leaf  12  is lifted so far from the carcass of the cabinet that it can be gripped from behind and can be pivoted into the completely open position shown in  FIGS. 5 and 6 . 
     A lever component  42  which is formed by two two-armed levers  42   a ,  42   b  which are rigidly connected to one another is pivotably mounted in the housing  28 . The end regions of the upper lever arms of the lever  42   a ,  42  engage around the ejector ram  30  in its opposing regions and are coupled to the ejector ram by way of a follower connection formed in each case by a projecting lug  50  engaging in an elongate groove  48  in the ejector ram  30 . The pivot mounting of the lever component  42  in the housing  28  also takes place—below the ejector ram  30 —in each case by a lug  52  which projects from the outer face of the lever  42   a ,  42   b , each of the lugs engaging in an associated bearing receptacle constructed as a groove  54  which is provided in the vertical direction in the inner face of the wall of the housing  28 . Thus in addition to the pivoting of the lever component  42  this mounting also allows a vertical displacement of the lever component  42  to the extent predetermined by the length of the groove  54 . 
     The end of the aforementioned rod component  33  within the housing is coupled in the end regions of the lower lever arms of the lever  42   a ,  42   b , wherein this end is constructed as an elongate loop-like eye  58  which is closed on both sides and which is traversed by a bolt  60  which is retained in the end region of the lower lever arms of the lever  42   a ,  42   b . Thus the consequence of this type of coupling of the rod component  33  on the lever component  42  is that transmission of a longitudinal movement of the rod component  33  from the eye  58  via the bolt  60  to the lower lever arms of the lever  42   a ,  42   b  and vice versa only takes place if the closed end of the eye  58  which is at the rear in the direction of movement rests on the bolt. In the case of reversal of the movement the eye can then first of all move freely on the bolt by the amount of the loop length of the eye  58  without entraining the lower lever arms of the lever  42   a ,  42   b  and thus without pivoting of the lever component  42 . Only when the opposing closed end of the eye  58  comes to rest on the bolt  60  is a further movement of the rod component  33  transmitted to the lever component  42  and converted into a pivoting of the lever component. Thus as a result between the functional components of the opening device  10  and the door leaf  12  a kinematic chain is created which leads from the closed position of the door leaf  12  shown in  FIGS. 1 ,  2  and  7   a ,  7   b  of the drawings via the partially opened position of the door leaf  12  shown in  FIGS. 3 ,  4  and  8   a ,  8   b  into the completely opened position of the door leaf shown in  FIGS. 5 ,  6  and  9   a ,  9   b . It can be seen from  FIGS. 7 to 9  that in the closed door position when the pawl  40  engaging in the latching recess is released the ejector ram  30  is pushed out of the housing  28 , whereby the lever component  42  still does not experience any pivoting due to the engaged connection via the lugs  50  engaging in the grooves  48 . If the door leaf  12  which is pivoted by the ejector ram  30  into the partially opened position is then opened further, the rod component  33  is initially freely entrained by the pivoting movement until the end of the eye  58  within the housing comes to rest on the bolt  60 . The lever component  42  is then pivoted due to the further pivoting movement of the door leaf into the position shown in  FIGS. 9   a ,  9   b , so that the ejector ram  30  is again forcibly retracted into the starting position by the pivoting movement in the appertaining groove  48 . The pawl  40  then engages in the latching recess  38  and locks the ejector ram  30  in the inserted position. The door leaf can then be pivoted back into the closed position largely without force, whereby the functional components of the opening device are then pivoted or displaced again into the starting position shown in  FIG. 7 . 
     The arrangement of a second embodiment of an opening device for a door leaf  12  according to the invention which is denoted overall by  110  is shown in  FIG. 10  in the front upper corner region of a cabinet carcass of which only the upper corner region of the side wall  14  is shown, whilst the top wall, which closes off the carcass at the top and which has the opening device  110  fixed on its inner face directed into the interior of the carcass, is not shown for the sake of clarity. The door leaf  12  is pivotable by means of conventional jointed hinges about a vertical axis and articulated on the side wall or supporting wall  14 . Only the upper hinge, which in the special case is constructed as a conventional four-bar hinge  16 , is shown in the drawing. 
     The opening device  110  has a rectangular housing  118  which is elongate in plan view and is intentionally kept small in the vertical direction and which is disposed with the upper flat face flush on the top wall of the carcass and with one of the shorter low transverse walls in flush abutment on the inner face of the side wall or supporting wall  14 . In the low front side wall  18   a  of the housing directed out of the interior of the carcass a through opening  120  is provided in the vicinity of the supporting wall  14  for a rod component  122 , of which the free end projecting out of the housing  118  engages so as to be pivotable about a vertical axis on a fixing bracket  124  fixed on the inner face of the door. 
     An ejector ram  128  with a flat elongate pressure surface which rests on the inner face of the door leaf in the closed state of the door leaf  12  is disposed in a through opening  126  which is spaced further from the supporting wall  14  in the housing end wall  118 . 
     In  FIG. 11  the door leaf  12  is shown in the aforementioned closed position a, and in addition further positions b to f between which the door leaf  12  is pivotable are shown by dash-dot lines. 
     Of these additional pivoted positions the position identified by b denotes a position in which the door leaf  12  is additionally forced by exertion of a pressure on its front face by a small angle in the direction of the interior of the carcass. In this case a thrust piece  131  of a trigger unit  130  also projects out of the front end face  118   a  of the housing  118  of the opening device and is forced by the door leaf  12  into the interior of the housing, and then in the manner described below in connection with  FIGS. 13   a  to  14   f  the trigger unit unlocks the ejector ram  128  which until then is retracted into the housing  118  in the position shown in  FIG. 10 , so that the ejector ram is forced out of the opening  126  by the bias of a spring  132  and forces the door leaf  12  into the position denoted by c. In this position the travel of the ejector ram  28  is ended and the door leaf  12  can be pivoted via the positions d and e into the completely opened position f, wherein in the pivot region of the door leaf  12  between the positions c and e via the rod component  122  articulated on the door leaf  12  the motion thereof is transmitted to a spring-biased slide to a tensioning and stopping device  134  provided in the housing  118 , of which the construction and operation are explained in greater detail below in connection with  FIGS. 12 to 14   f.    
     The opening device  110  is shown in  FIG. 12  in an exploded view which shows the construction of the individual components. The housing  118  has an upper and a lower flat top wall  118   b  and  118   c , each rectangular in plan view, which in the proper mounted position are retained so as to be aligned in a predetermined spacing with respect to one another by—in the illustrated case—four cylindrical distance pieces  136  each provided with a central through hole, wherein the elongate front side wall  118   a  is formed by strip-shaped regions of the original flat sheet metal blank of the top wall which are bent upwards at right angles from the lower top wall  118   c . The through opening  120  for the rod component  122  and the through opening  126  for the ejector ram  128  as well as the through opening for the thrust piece  131  are formed by stamping out of the bent side wall  118   a . The height of the distance pieces  136  is chosen to be equal to the height of the front side wall  118   a  measured in the vertical direction, so that the elongate side wall  118   a  closes the front face of the housing  118 —except for the aforementioned stamped-out openings. 
     The housing  118  can also be closed peripherally along the other boundary edges of the top walls  118   b  and  118   c  by upwardly bent strip-shaped sheet metal sections. In  FIG. 3  in addition to the strip-shaped side wall  118   a  only the strip-shaped end wall  118   d  which is bent upwards from the top wall  18   c  shown in the drawing at bottom left of the lower top wall  18   c.    
     Between the top walls  118   b ,  118   c  a two-armed lever component  138  is mounted in the housing  118  so as to be pivotable about a vertical axis, the lever arms  138   a ,  138   b  of which are directed in each case in the opposite direction to the narrower side walls of the housing  118 . In the end region of the lever arm  138   a  the ejector ram  128  is connected by way of an extension  138   c  bent down from the lever arm  138   a  so as to be pivotable and additionally to be lateral displaceable to a limited extent. The ejector ram designed as a flat plate component is guided with its flat thrust face  128   a  directed towards the door leaf in the through opening  126  between the top walls  118   b ,  118   c . The aforementioned spring  132  under compression pretension acts on the lever arm  138   a  for the purpose of a pivoting movement which pushes the ejector ram  128  out of the through opening until the lever arm  138   a  rests on the inner face of the side wall  118   a.    
     Apart from the free end of the lever arm  138   a  a latching component constructed as a pivot lever  140  is disposed in the housing and has on its free end facing the free end of the lever arm  138   a  a locking projection  140   a  which in the retracted locked position of the ejector ram  128  engages under the free end of the lever component  138   a  and fixes the lever component in the retracted locked position against the bias of the spring  132  acting on it. 
     On its end opposite the end on the pivot bearing side the pivot lever  140  is coupled via an elongate tension/compression element  142  to the free end of a lever arm  144   a  of a toggle lever  144 . The toggle lever  144  is part of the aforementioned trigger unit  130 . The second lever arm  144   b  of the toggle lever is coupled to an elongate ram  146  which is biased under compression pretension in the direction of a position where it is forced out of the housing  118  and on the free end of which remote from the toggle lever there is fixed the thrust piece  131  which projects by a small amount from the front face of the side wall. 
     The toggle lever  144  can be pivoted via the ram  146  engaging on the lever arm  144   b  by pressing of the thrust piece  131  into the interior of the housing in such a way that by way of the tension/compression element  142  the lever arm  144   a  of the toggle lever pivots the pivot lever  140 , wherein the locking projection  140   a  of the pivot lever is drawn back from its position where it engages under the free end of the lever am  138   a . Due to the compression pretension of the spring  132  the lever component  138  is then pivoted and the ejector ram  128  coupled to the lever arm  138   a  is forced outwards out of the retracted locked position. The pressure surface  128   a  of the ejector ram  128  resting on the inner face of the closed door leaf  12  pivots the door leaf into the partially opened position denoted by c in  FIG. 11 . 
     The lever arm  138   b  of the two-armed lever component  138  co-operates with the aforementioned tensioning and stopping device  134  which has a flat slide  150  which is guided so as to be horizontally displaceable parallel to the supporting wall  14  of the carcass in a guide housing  148  disposed in the housing, wherein one end of the rod component  122  is coupled so as to be pivotable and longitudinally displaceable by a predetermined amount in the front end region of the slide on the door leaf side. The other end of the rod component  122  is—as mentioned above—articulated on the fixing bracket fixed on the inner face of the door leaf. Thus when the door leaf  12  is opened out of the closed position into the open position the pivoting movements of the door leaf are transmitted via the rod component  122  to the slide  150 , that is to say the slide is withdrawn from the position inserted into the guide housing  148  ( FIG. 13   a  and  FIG. 14   b ) as far as the position shown in  FIGS. 13   f  and  14   f  in which its front end coupled to the rod component  122  is withdrawn through the through opening  120  to a point in front of the housing side wall  118   a.    
     A control groove  152  extending in a substantially straight line over the greater part of its length in the slide withdrawal direction is made in the slide, the said control groove being rounded on its front end outside the carcass and merging into a short end portion  152   a  extending at right angles to the straight region. A control projection  156  projecting from the underside of a segment-shaped control disc  154  pivotably mounted on the guide housing  148  engages in the control groove. When the door leaf is opened the outer segment surface  156   a  lying opposite the pivot axis of the control disc  154  comes to rest on a matching surface of the lever arm  138   b  which is then pivoted during its pivoting action by the co-operation of the control projection  156  engaging in the control groove  152  and pivots the lever arm  138   b  in the sense of pivoting the lever component in the clockwise direction, so that the lever arm  138   a  of the lever component  138  retracts the ejector ram  128  into the interior of the housing. In the completely retracted locked position of the ejector ram  128  the locking projection  140   a  then passes again below the free end of the lever arm  138   a  and the ejector ram  128  is locked in the retracted position. The door leaf  12  can then be led back out of the completely opened position ( FIG. 13   f ,  FIG. 14   f ) practically without force into the closed position ( FIG. 13   b  and  FIG. 14   b ), wherein the slide  150  is pushed back into the housing  118  via the rod component  122  and the control disc  154  is pivoted clockwise by way of its control groove  152  and the control projection  156  so that its sector-shaped control surface is lifted off from the matching control surface on the lever arm  138   b  as the closed position is approached and the control projection  156  passes over into the end portion  152   a  of the control groove  152  as the closed position is reached. 
     The co-operation of the functional components of the opening device  110 , and their respective position in the closed or open positions of the door leaf  12  denoted by a to f in  FIG. 11 , is shown in  FIGS. 13   a  to  13   f  and  14   a  to  14   f  respectively. It can be seen that when the door leaf  12  is pushed by a very small angular amount in the direction of the interior of the cabinet carcass out of the position a into the position b the inner face of the door leaf  12  the thrust piece  131  pivots the lever arm  144   e  of the toggle lever  144  via the ram  146 , whereby the second lever arm  144   a  is retracted by way of the tension/compression element  142  pivoting the pivot lever  140  out of the position in which it engages with its locking projection  140   a  under the free end of the lever arm  138   a  of the lever component  138 . Due to the bias of the spring  132  acting on the lever arm  138   a  the lever arm  138   a  which is then unlocked and the ejector ram  126  coupled thereto is forced out of its position in which it is almost completely retracted into the housing through the through opening  126  and out of the housing, the door leaf  12  being pivoted up automatically into the position c. However, further pivoting of the lever arm  138   a  is then prevented by contact of the lever arm  138   b  of the lever arm  38   a  on the adjacent distance piece  136 , so that as opening proceeds further the door leaf  12  is lifted off from the pressure surface  128   a  of the ejector ram  128  ( FIG. 13   d ). The slide  150  of the tensioning and stopping device  134  is then drawn forwards by way of the rod component  122  articulated on the fixing bracket  124 , wherein in co-operation with the control projection  156  engaging in the control groove  152  of the slide  150  the control disc  154  is pivoted and in turn by pressure on the lever arm  138   b  pivots the lever component  138  back against the tension of the spring  132 . Due to the coupling of the ejector ram  128  on the lever arm  138   a  of the lever component  138  this latter is then retracted into the housing  118 . When the position of the components illustrated in  FIG. 13   f  is reached, the free end of the lever arm  138   a  passes over the locking projection  140   a  of the pivot lever  140  and thus is locked in the retracted position of the ejector ram  128 . The door leaf  12  can then be pivoted back into the closed position largely without force, the slide  150  then being pushed back by the rod component  122  into the guide housing  148 . In this displacement operation, as the closed position of the door leaf is approached the control disc  154  is pivoted back so that it is lifted off from the matching surface on the lever arm  138   b . Then as the closed position is approached the control projection  156  moves over into the end portion  152   a  of the control groove  152 . 
     It can be seen that within the scope of the idea underlying the invention modifications and variants of the described embodiments of the opening devices can be made according to the invention. Thus the opening device of the first embodiment which is described as an assembly to be installed separately can basically also be combined with the hinges of a cabinet or can be integrated into the hinges. In this case it is merely important that the kinematic construction is such that the ejector ram which displaces the door leaf after the release of the pawl from the latching recess at the start of the opening operation is displaced again as pivoting proceeds further into the completely open position by way of the rod component articulated on the door leaf, the ejector ram being moved back into the retracted position and automatically held locked in this position until the latching engagement of the pawl is released again by deliberate manipulation by a user. The manipulation of the pawl can take pace for example by remote control via a Bowden cable or a push or pull rod linked to an outer actuating element. As an alternative electrical actuation is also conceivable, in which the pawl is constructed as an armature or is connected to such an armature which is pulled up by application of a voltage to an associated electric coil. In this connection wireless remote triggering of the armature coil is also conceivable. 
     Also in the second embodiment parts of the functional groups created in the opening device  10  by the co-operation of mechanical components can be replaced by electrical or electronic components such as proximity sensors, magnetic armature components, etc.