Closing device, extension runner having a closing device as well as furniture item having an extension runner

A closing device for closing a movably mounted drawer relative to a furniture carcass, including a catch piece releasably couplable with an entrainment mechanism of the drawer and mounted to be movable along a displacement portion, and an energy storage mechanism which is chargeable by a displacement movement of the catch piece. The catch piece includes a hold state at the end of and at the beginning of the displacement portion and the catch piece is locked in the hold state at the end of the displacement portion, holds the energy of the energy storage mechanism and allows the drawer to be decoupled. The catch piece is pivotable and carries out a pivoting movement along the displacement portion between the two holding states over a path of more than 20% of the displacement portion when the catch piece is displaced.

FIELD OF THE INVENTION

The invention relates to a closing device, an extension runner having a closing device, and a furniture item having an extension runner.

BACKGROUND OF THE INVENTION

With reference toFIGS. 5-8German Utility Patent No. 20 2004 006 410 U1 (the entire contents of which are incorporated herein by reference) discloses an automatic closing mechanism for drawer runners with a guide rail12which is to be fastened on a carcass wall CW of an item of furniture. The drawer D is arranged on a drawer rail14which is mounted so as to be displaceable relative to the guide rail12. A movable catch component24, which is prestressed in a bistable manner in two end positions which are spaced apart from one another in the direction of movement of the drawer by means of a spring arrangement with an elongated helical spring40, is provided in a catch housing22on the guide rail or carcass rail12. The catch component24has a receiving means36for an entrainment means28(FIG. 8) which is provided on the other rail14. The entrainment means28moves into the receiving means36when approaching a closed position when there is a relative displacement of the rails and pivots the prestressed movable catch component24, as a result of which the catch component24is unlocked from the associated end position. This results in the catch component24being moved into the other end position under the effect of the spring tension and the associated rail with drawer also being moved into the end position by means of the entrainment means28which is held in the receiving means, which provides the closed position of the drawer. A damping device44, in which is movably arranged a damper element which communicates with the catch component24by means of transmission elements36a, is provided in the catch housing22.

When the drawer is opened, the catch component24is moved in the opening direction by means of the entrainment means28which is coupled into the catch component24, as a result of which the helical spring40is tensioned until the catch component24is left in the end position locked by the entrainment means28. The operation tensioning the spring calls for a not inconsiderable force to be applied by the user when opening the drawer.

SUMMARY OF THE INVENTION

The object underlying the present invention is to provide a closing device of the type designated in the introduction which comprises a characteristic that is improved with regard to the effort required for charging an energy storage means.

The present invention proceeds from a closing device for drawers for closing a movably mounted drawer into the closed end position relative to a furniture carcass, said closing device having a catch piece, which is releasably couplable with an entrainment means of the drawer and is mounted so as to be movable along a displacement portion, as well as having an energy storage means which is chargeable by means of a displacement movement of the catch piece, wherein the catch piece comprises a hold state at the end of and at the beginning of the displacement portion and wherein the catch piece is locked in the hold state at the end of the displacement portion, holds the energy of the energy storage means and allows the drawer to be decoupled. The core of the present invention now consists in that the catch piece is arranged so as to be pivotable and carries out a pivoting movement along the displacement portion between the two holding states over a path of more than 20% of the displacement portion when the catch piece is displaced. The pivoting movement of the catch piece is preferably effected along a guide track, a supporting point of the catch piece sliding along on the guide track. The pivoting movement is preferably further defined in such a manner that the supporting point, as a result of the pivoting movement of the catch piece, moves closer and closer to a line along which applied energy of the energy storage means on the catch piece runs. As a result, an ever increasing part of the energy of the energy storage means can be transmitted from the supporting point of the catch piece to the guide track, as a result of which the energy a user has to apply decreases. The user then simply has to apply the proportion of energy of the energy storage means which cannot be diverted to the guide track from the supporting point. In the end position, the supporting point of the catch piece on the guide track has arrived, for example, at a position of the guide track at which the guide track slopes so far with reference to the applied energy, and consequently the catch piece has pivoted so far, that the catch piece is automatically held in said position without any force being applied.

The guide track preferably slopes, when viewed in the opening direction of the drawer, from a horizontal alignment into an increasingly vertical alignment. A tangent at the end of the guide track is preferably vertical or almost vertical, where applicable even slopes slightly beyond the vertical such that to a certain extent the supporting point is able to engage behind the curve.

As a result of the pivoting movement of the catch piece, certainly the extension path is extended with a predefined spring tensioning path, however by means of the pivoting movement on a guide track the possibility is created for the effort expended by an operator on the drawer for charging the energy storage means, in particular a spring, albeit a self-extending spring, to remain the same where applicable, for example when arrived at the end of the guide track, even to decrease to the value of zero, at which the catch piece is then automatically held on the guide track and the entrainment means is preferably released from the catch piece in this position.

The pivoting movement is preferably effected over more than 30, 40, 50, 60, 80, 90% of the displacement path, where applicable from the beginning. The possibility of holding the energy for charging the energy storage means, in particular a spring, albeit the self-tensioning spring, substantially equal over the displacement portion is provided as a result. This is achieved in an increasing manner as the pivoting movement is realized along an ever increasing part of the displacement portion.

In a preferred development of the present invention, the pivoting movement is forcibly actuated over a guide track. As a result of the forcible actuation, which preferably extends in a sloping manner with respect to the displacement path of the catch piece, it is possible for the catch piece to be always supported unambiguously on the guide track and consequently to absorb the energy of the energy storage means. The energy of the energy storage means can act, for example, on a pivot axis of the catch piece. In the end position, the acting energy of the energy storage means, in particular the spring force of a tension spring, the pivot axis of the catch piece and the supporting point of the catch piece on the guide track are preferably arranged along a line, at the same time with the guide track preferably substantially vertically inclined. As a result, it is possible in this position for the catch piece to be held automatically in said position even if external forces are removed and thus to be able to be utilized as a holding state at the end of the displacement portion thereby holding the energy of the energy storing means.

In an advantageous development of the invention, the pivoting movement of the catch piece is predefined as a result of abutment against a curved element. The curved element preferably defines the guide track.

In a preferred development of the invention, the catch piece comprises an abutment element which is supported on the guide track. The abutment element is preferably supported on the curved element during a pivoting movement. As a result, by means of the abutment element the curved element is able to absorb forces which act on the catch piece such that said energy does not have to be provided by the user.

In order to be able to keep a constant connection to the entrainment means in the coupled state when the catch piece is pivoting, it is further proposed that the catch piece includes a receiving region for the entrainment means in which the entrainment means is able to be moved relative to the catch piece during a pivoting movement of the catch piece with the entrainment means not-uncoupled.

An advantageous simple development of the receiving region can be developed such that the receiving region has a slot-like recess. The entrainment means can be moved in said slot-like recess during a pivoting movement of the catch piece.

In an advantageous manner, the receiving region, in particular the slot-like recess for the entrainment means is matched in such a manner to the pivoting movement of the preferably forcibly actuated catch piece that when the catch piece is pivoted, the entrainment means is moved in the receiving region extensively without any additional expenditure of force. This is preferably a curved slot.

In a further preferred development of the invention, the receiving region is open on one side. The opening on one side makes it possible for the entrainment means to be able to be uncoupled from the catch piece, in particular in an end position with the energy storage means charged.

DETAILED DESCRIPTION OF THE INVENTION

FIGS. 1 to 3show the components catch piece entrainment means2and curved element3of a closing device with different positions of the catch piece3along a displacement path.

The catch piece1has a pivot axis4, a curved slot5for receiving the entrainment means2as well as an abutment element6. The abutment element6slides along a curved track7of the curved element3with the catch piece1being displaced along a displacement portion out of a start position according toFIG. 1into an end position according toFIG. 3.

A user encounters the following conditions when the catch piece is displaced as a result of, for example, displacing a drawer (not shown) with regard to the force that he has to expend:

A force FBof a user acts on the entrainment means2by means of the drawer which is coupled with the entrainment means2. On the other side, the energy of an energy storing means which pulls the drawer closed, for example, a spring force FFaccording to the force marked inFIG. 1, abuts against the pivot axis4.

Normally, the opening force increases corresponding to the spring force according to Hooke's law FF=D·s, wherein D is the spring constant and s the opening path. A user must then apply an opening force FBwhich corresponds to the spring force FF.

The curved element3with the abutment element6of the catch piece1which is moved along the same results, however, in other conditions for the user with regard to the opening force FB.

InFIG. 1, the user starts with a force FBwhich corresponds substantially to the spring force FF. In this case, the spacing between the entrainment means, on which the force FBacts, and the pivot axis comprises the value a.

Along the path (on the right-hand side inFIGS. 2 and 3) the abutment element6slides on the curved track7which slopes downward, as a result of which the catch piece1is pivoted clockwise. The abutment element6, in this case, remains fixedly in the abutment on the curved track7as a result of the force conditions which the entrainment means generates in the slot5. The result of the sloping curved track is that a larger and larger proportion of the restoring forces of a spring (not shown) are able to be supported on the curved element3by means of the abutment element6, as a result of which the force FBwhich is decisive to the user is not increased in a linear manner as expected, but as shown in the force-distance diagram according toFIG. 4increases initially somewhat, then even falls slightly and at the end, when the curved track is more clearly sloping, where applicable up to the vertical, falls away severely, possibly to zero, which is not shown, however, in the force-distance diagram. A conventional closing device, as is disclosed, for example, in German Utility Patent No. 20 2004 006 410 U1, is shown as curve8in the force-distance diagram. Corresponding to Hooke's law, the curve is a substantially straight line. The force-distance diagram for the closing device according to the invention is represented by the curve9which certainly does show a linear force increase at the beginning, but then falls away slightly and finally reflects a sharply decreasing force progression.

The situation is symbolized by an end point inFIG. 3. The catch piece1has been pivoted so far that the entrainment means2is able to move out of the slot5, which is open on one side, which results in the drawer, from this point in time, then being able to move freely further in the opening direction. The catch piece1has preferably arrived, as a result of the curved track, in a position such that the catch piece is held there itself, that is to say the forces of the spring FFdo not succeed in allowing the catch piece to snap back along the curved track.

In the position of the release, the entrainment means2is at a spacing c from the pivot axis of the catch piece when viewed in the opening direction.

All in all, the path5of the entrainment means has been lengthened by a distance c-a by the pivoting movement up to the release position. Such lengthening of the path does not normally take place in the case of a conventional closing device. For, in this case, the catch piece is simply pivoted right at the end along a very short path portion of a displacement path of the catch piece in order to move the catch piece into a locked position, and to release an entrainment means. However, the longer displacement path as result of pivoting the catch piece1means that the force required by the user on the entrainment means2when opening is reduced. The opening movement for a drawer is then more pleasant for the user.

A closing device according to the invention can be used, for example, in an automatic closing mechanism which is described in German Utility Patent No. 20 2004 006 410 U1. Reference is hereby made explicitly to the features and details provided therein.

LIST OF REFERENCES