FIELD OF THE INVENTION
The invention relates to a device for pushing out a furniture part and a piece of furniture.
BACKGROUND OF THE INVENTION
Devices for pushing out a furniture part which is accommodated in a movable manner on a fixed furniture part are already known. The pushing-out operation can take place, for example, via a pivotable pushing-out lever which can be driven by a drive unit, is fitted on one of the two furniture parts and is temporarily in contact with the other furniture part in order to push out the movable furniture part. The movable furniture part may be a drawer, door, shutter or some other movable furniture part. The pushing-out lever comes into contact with the other furniture part, during the pushing-out operation, within an abutment region which is present on the pushing-out lever, contact being eliminated following the pushing-out operation.
Various requirements have to be met in the design of the pushing-out device. On the one hand, the pushing-out device should be as cost-effective, robust and space-saving as possible. On the other hand, it is sought to make it possible for the movable furniture part to execute comparable pushing-out movements, in particular even when it has to move, for example on account of variable loading, vastly different masses in each case.
SUMMARY OF THE INVENTION
The object of the present invention is to improve a device of the type mentioned in the introduction in technical and economic terms and to provide a piece of furniture which has a corresponding device.
The invention is based, in the first instance, on a device for pushing out a furniture part which is accommodated in a movable manner on a fixed furniture part, having a pushing-out lever which can be driven via a drive unit, is fitted on one of the two furniture parts and is temporarily in contact with the other furniture part in order to push out the movable furniture part, and the pushing-out lever has an abutment region within which the contact between the pushing-out lever and the other furniture part takes place, it being possible for the pushing-out lever to be driven, the intention being for the contact between the pushing-out lever and the other furniture part to be eliminated during a pushing-out operation. It is an essential aspect of the invention that the abutment region has an inflection. It is thus possible, via the configuration of the abutment region on the pushing-out lever or by appropriate shaping of the pushing-out lever, to realize a desired profile for the pushing-out movement and/or advantageous pushing-out characteristics. In particular different effective lever lengths are thus achieved during the pushing-out operation by way of a relatively straightforwardly modified pushing-out lever. Different effective lever lengths also give rise to different forces and/or moments which can be transmitted to the other furniture part by the pushing-out lever during the pushing-out operation. This may be advantageous, in particular, when, for example at the beginning of the pushing-out movement, comparatively large forces and/or moments are necessary in order to be able to move the movable furniture part, in particular in order to overcome a standstill position in the closed state of the movable furniture part. A decisive effective lever length of the pushing-out lever here is one which is dependent on the lever geometry and/or on the type of inflection. It is thus possible here to realize a shorter lever length in a first phase of the pushing-out operation than at a later point in time of the pushing-out operation. The inflection in the abutment region will also provide contact with the other furniture part at the beginning of the pushing-out movement. It is thus advantageously possible for the furniture part which is to be moved to be subjected to forces and/or moments by the pushing-out lever for a pushing-out action. Furthermore, an inflection in the abutment region makes it possible for the pushing-out lever to be accommodated in a particularly space-saving manner. The inflection may describe a comparatively flat angle of inflection, for example on the side directed away from the abutment region, of between 120 and 170 degrees or below.
It is a further essential aspect of the invention that the pushing-out lever is designed to deform elastically during the pushing-out operation. Elastic bending at least of certain parts of the pushing-out lever, in particular of the abutment region, under load during the pushing-out operation can make it possible to influence the pushing-out operation, in particular the duration and magnitude of the forces and/or moments which can be transmitted by the pushing-out lever. The pushing-out operation can thus be adapted to different conditions, e.g. to different masses which have to be moved during the pushing-out operation. This can be achieved with a resiliently designed pushing-out lever since the latter, depending on the extent of elastic deformation during the pushing-out operation, and the change in this deformation over time, makes correspondingly different pushing-out actions possible. Depending on the magnitude of the mass which is to be moved here, it is possible to have different relationships between the proportions of the driven distance and of the non-driven, follow-on distance following the end of the driving action, in order always to obtain approximately the same pushing-out distance overall. The deliberately set-up, reproducible elasticity of the pushing-out lever, this elasticity having a marked effect on the pushing-out operation, makes it possible to realize, so to speak, a pushing-out action which adjusts automatically to different loadings or other variable boundary conditions of the movable furniture part.
The characteristics of the pushing-out operation which are dependent on the elasticity of the pushing-out lever may be influenced, for example, by different material properties of the elastically active part of the pushing-out lever or appropriate shaping or positioning of the elastically deforming regions of the pushing-out lever.
Furthermore, it is proposed that the pushing-out lever is designed such that a maximum change in position of one end of an elastic part of the pushing-out lever brought about by the elastic deformation during the pushing-out operation is at least 2%, in particular at least 5%, in relation to the length of the elastic part of the pushing-out lever. If we consider, for example, an elastic part of the pushing-out lever which bends around a fitting point, the length of the elastic part of the pushing-out lever is to be understood as approximately the distance between the fitting point and that end of the elastic part of the pushing-out lever which is remote from the fitting point. With, as proposed, elastic deformation of the pushing-out lever as a whole, and/or by way of elastically behaving sections of the pushing-out lever, it is possible to achieve, in a particularly reliable manner, desired self-adjustment of the pushing-out operations which is dependent on different boundary conditions, e.g. the magnitude of the masses which are to be moved.
The pushing-out lever is advantageously designed as an angled lever with, in the abutment region, an inflection by way of which two essentially rectilinear sections of the abutment region are oriented at an angle in relation to one another. An inflection, within the context of the invention, is understood to mean, in particular, that the abutment region is not curved, or such a profile should be avoided. Two sections which are essentially rectilinear in the region of inflection and are oriented at an angle in relation to one another allow the pushing-out lever to be designed in a relatively straightforward and space-saving manner. If appropriate, it is possible, for space-related reasons, for the inflection in a rectilinear pushing-out lever, which is rectilinear in particular in a starting position, to form only as the pushing-out operation begins or the pushing-out lever begins to pivot, for example, when the inflection is articulated.
An inflection makes it possible to realize a precise change in an effective lever length during a pushing-out movement. For example, a pushing-out lever with an inflection in the abutment region can provide for a first effective lever length in a first phase of the pushing-out movement and for a further effective lever length as the pushing-out movement of the pushing-out lever progresses.
Moreover, it is preferred if the pushing-out lever has a part which behaves essentially rigidly during the pushing-out operation and a part which deforms elastically during the pushing-out operation and comprises, in particular, the abutment region. The pushing-out lever can thus be adapted particularly straightforwardly to different desired pushing-out profiles. The coordination of the elastically deforming part and of an essentially rigid part of the pushing-out lever means that the pushing-out lever can subject the other furniture part to markedly different forces which act during the pushing-out operation. Moreover, automatic adaption of the pushing-out lever can be achieved during the pushing-out operation. It is, for example, also possible for a rigid basic body of the pushing-out lever, depending on the elasticity desired, to have different elastically deforming parts of the pushing-out lever fitted on it. The two parts may be separate components or may be formed integrally.
Furthermore, it is proposed that the abutment region of the pushing-out lever is designed with multiple inflections. A multiple-inflection arrangement or a polygonal shape of the abutment region can make possible a multiply extending effective lever length as the lever movement continues during the pushing-out operation.
It is particularly advantageous if an inflection in the abutment region is configured rigidly, in which case there is no change, during the pushing-out operation, in an angle of inflection formed by the relevant inflection. It is thus possible for the pushing-out lever to be produced, in particular, straightforwardly and to be comparatively stable.
As an alternative, it may be advantageous for an inflection in the abutment region to be designed such that it can be changed elastically under load. In particular the inflection in the abutment region may be designed such that it can be changed elastically under load so that, during the pushing-out operation, a change in an angle of inflection formed by the relevant inflection can take place. The angle of inflection can be changed, for example, by one or more inflections being articulated. It is thus also possible, for example, in a standby position before or after a pushing-out operation, for the pushing-out lever to straighten out completely, which is a relatively space-saving maneuver. Moreover, when a limit loading to which the pushing-out lever is subjected is exceeded, this pushing-out lever can yield if appropriate at the points of inflection, as a result of which damage can be prevented.
It is a further essential aspect of the invention that the pushing-out lever is configured in order to allow a pushing-out operation in the manner of a toggle mechanism. A toggle mechanism makes it possible, in particular with an acute toggle angle, to transmit high forces to a furniture part which is to be moved. Moreover, a toggle mechanism can be accommodated in a particularly space-saving manner in a straightened-out position.
It is advantageous here in particular if the pushing-out lever comprises a toggle which is fitted on one of the furniture parts and has limbs which can be angled in relation to one another in a head section, the head section coming into direct abutment against the other furniture part during the pushing-out operation. This makes it possible to realize a particularly effective transmission of forces to the other furniture part during the pushing-out operation.
Moreover, it is advantageous to provide an overload-prevention means which is intended for the toggle mechanism and allows the pushing-out lever to yield counter to a movement which is necessary for the pushing-out operation. In the case of the furniture part which is to be moved being subjected to unforeseen or briefly occurring pronounced mechanical loading counter to a pushing-out direction, it is possible to avoid damage to the toggle mechanism and/or to a furniture part.
The invention further comprises a pushing-out lever which is, in particular, telescopic. It is thus conceivable for the lever to be movable with driving action and to have telescopic sections which can be rotated in relation to one another. The lever can be telescoped via, for example, a rotary guide or a helical groove with engagement sections running therein. For example, a pushing-out lever may comprise a plurality of pushing-out lever elements which are nested one inside the other in the manner of cups, can be telescoped in relation to one another by rotation and can be accommodated in a compact manner or extended.
The invention additionally relates to a piece of furniture with a movable furniture part which is accommodated in a movable manner on a fixed furniture part, a device like that explained above being provided. The advantages disclosed can thus also be achieved for a corresponding furniture part.
For safety reasons, it is necessary, in the event of a false start of the system, for the movable furniture part of the latter, e.g. a drawer, not to extend or, in the event of overloading, for the extending operation of the drawer to be interrupted. Since, in most cases, such errors are based on an error in the control means, the appropriate safety-related intervention must not take place by way of defective control means. This is done by the lever being of two-part design and the two parts being connected to a rotary articulation. The torques which occur in this rotary articulation are safeguarded mechanically preferably via an elastic spring. An elastic spring has the advantage that the envisaged spring force need only be achieved briefly in order for the profile shape of the elastic spring to be changed such that a much weaker leaf-spring profile is no longer able to support the rest of the torques and the cam cycle can be readily brought to an end. If the system moves into the basic position, and the top dead center is passed, the elastic spring can force the two lever parts back into the original position again as a result of the spring loading being eliminated.
It is advantageous in principle in the case of the proposed arrangement if, irrespective of the method of fitting the movable furniture part on the fixed furniture part, the pushing-out device can be fitted universally and/or can be easily retrofitted. In particular there is no need to take any additional measures for locking the movable furniture part in the closure position, since the movable furniture part can be retained in the closure position via conventional locking means, e.g. an automatic retraction mechanism.
Furniture parts are to be understood predominantly as furniture parts for kitchen furniture and furniture for the home in general, but the expression furniture parts, within the context of the invention, may also extend to drawers, doors and shutters on other arrangements, for example to a drawer on a tool cabinet or carriage.
BRIEF DESCRIPTION OF THE DRAWINGS
By way of the figures, further details and features of the invention will be explained in more detail using highly schematically illustrated exemplary embodiments. The figures use partially the same designations for corresponding components of different exemplary embodiments.
FIG. 1 shows a perspective view of a schematically illustrated piece of furniture with a drawer;
FIG. 2 shows the piece of furniture according to FIG. 1 with individual parts left out, the drawer being illustrated in the open state;
FIGS. 3 to 6 show a view from above of the piece of furniture according to FIG. 1 without a top part, the drawer being illustrated in different positions before, during and after a pushing-out operation;
FIGS. 7
a to 7c show a full view, in perspective, a partly sectional view and a partial front view of the pushing-out device which is used in FIGS. 3 to 6, is fitted on a mount and is intended for pushing out the drawer, the pushing-out lever here being pivoted back to the full extent;
FIGS. 8
a to 8c show a further full view, in perspective, a partly sectional view and a partial front view of the arrangement according to FIGS. 7a to 7c in a first pivoting position of the pushing-out lever, a housing section of the pushing-out device having been left out of FIG. 8a;
FIGS. 8
d and 8e show a partly sectional view and a partial front view of the pushing-out device according to FIGS. 7a to 8c in a second pivoting position of the pushing-out lever;
FIG. 9 shows a schematic illustration, in perspective, of a control wheel of the pushing-out device according to FIGS. 7a to 8e;
FIG. 10 shows a further exemplary embodiment of a pushing-out device according to the invention;
FIG. 11 shows a further exemplary embodiment of a pushing-out device according to the invention;
FIG. 12 shows a further perspective exemplary embodiment of a pushing-out device according to the invention with a front housing left out;
FIGS. 13 to 15 show the pushing-out device according to FIG. 12 from above with the pushing-out lever pivoted back and in two positions in which it has been pivoted to different extents;
FIGS. 16 and 17 show a drawer and pushing-out lever of a further pushing-out device shown merely as a schematic diagram, the arrangement being shown with the drawer closed and during the pushing-out operation;
FIG. 18 shows, in accordance with the illustration from FIG. 16, a drawer with an alternative pushing-out lever according to the invention;
FIGS. 19 to 23
b show perspective views, front views and views from above of a further alternative pushing-out device according to the invention in different positions;
FIGS. 24 to 26 show a pushing-out lever according to the invention as seen in perspective and from the side, with individual parts left out;
FIG. 27 shows a further pushing-out lever according to the invention which is very similar to the pushing-out lever from FIGS. 24 to 26 and is shown in a cut-away state from the side during the pushing-out operation;
FIGS. 28 and 29 show the pushing-out lever according to FIG. 27 with activated overload-prevention means as seen in a full view from the side and with certain parts left out or cut away;
FIGS. 30 to 33 show a piece of furniture in three different states which is illustrated in perspective, obliquely from above, is shown in a partly cut-away state, or with certain parts left out, and has a highly schematic pushing-out device;
FIGS. 34 and 34
a show the piece of furniture in the same view as in FIG. 31, and in an enlarged detail-form view, in a loaded state;
FIGS. 35 and 35
a show the piece of furniture in the same view as in FIG. 32, and in an enlarged detail-form view, in a further state; and
FIGS. 36 and 37 each show a schematic diagram, in side view, of different pushing-out devices according to the invention during the operation of pushing out a drawer.
DETAILED DESCRIPTION OF THE INVENTION
FIGS. 1 and 2 show a piece of furniture 1 with a basic structure 2 and a drawer 3 which can be displaced in the basic structure 2 via a pull-out guide 4. The pull-out guide 4 comprises, in particular, a full-extension mechanism which is known per se and has a drawer-mounted drawer rail, a basic-structure-mounted fixed rail and a central rail accommodated in a movable manner therebetween. In FIG. 1, the drawer 3 is located in a closure position in which a front gap 5 of for example a few millimeters is formed between the basic structure 2 and an inner side of a front portion 3a of the drawer 3. The front portion 3a does not have any handle in the example shown, although it is also possible for a handle to be present.
The front gap serves predominantly, by virtue of someone or something pushing on the front portion 3a, to allow a triggering command for a pushing-out operation in which the drawer 3 can be moved a few millimeters in the direction of the basic structure 2, with the front gap 5 being reduced in the process. A triggered pushing-out operation is executed by a pushing-out device 6 according to the invention. If, in the state shown in FIG. 1, the closed drawer 3 is pushed to some extent, a movement of the drawer can be registered via, for example, corresponding sensors (not illustrated), as a result of which a pushing-out operation is triggered by means of the pushing-out device 6.
FIG. 2 shows the fully opened drawer 3 in the basic structure 2, which is shown without a side wall, rear wall and top part. A pushing-out lever 7 of the pushing-out device 6 is illustrated in a fully pivoted position. The pushing-out lever 7 can be pivoted for example in relation to the rear wall (not illustrated) of the basic furniture structure 2 through a maximum pivoting angle of approximately 80 to more or less 90 degrees or more. Pivoting of the pushing-out lever 7 causes the latter to butt against the outside of a rear wall 3b of the drawer 3, and the drawer 3 can push away out of a closure position, in particular can move out of the closed position according to FIG. 1 in the opening direction by a distance of, for example, approximately 30 to 70 mm. For this purpose, a drive unit concealed by a housing part moves the pushing-out lever 7 with driving action out of an abutting or swung-back position into the pivoting position shown in FIG. 2. Contact between the rear wall 3b and the pushing-out lever 7 is then eliminated, and the moving drawer 3 can move freely a bit further. Then, preferably when the drawer 3 moves freely a bit further, or as soon as the contact between the rear wall 3b and the pushing-out lever 7 has been eliminated, in particular the drive unit pivots the pushing-out lever 7 back into the swung-back position in order to be ready for the next pivoting or pushing-out operation. When the pushing-out lever 7 is in the abutting position (not shown), its longitudinal axis is oriented approximately parallel to the rear wall 3b of the drawer and/or to crossmembers 8a, 8b.
The pushing-out device 6 is clipped in releasably over the two crossmembers 8a and 8b. The two crossmembers 8a, 8b are themselves accommodated in accommodating flanges 9a and 9b which are fastened on the side walls of the basic furniture structure 2.
The pushing-out device may also be fastened on the drawer 3 and moved along therewith, in which case the pushing-out lever 7 can come into contact, for example, with the rear wall of the basic structure 2 at least for pushing-out purposes.
FIG. 2 shows the pushing-out lever 7 in its fully pivoted position, in order to give a good view of the pushing-out lever, although the pushing-out lever 7 is usually already located in its pivoted-back position, or in its rest position, again when the drawer 3 is fully opened.
FIGS. 3 to 6 illustrate a piece of furniture 1 from above with a top side of the basic structure 2 left out, and this piece of furniture has a pushing-out device 6 which is modified in relation to the pushing-out device according to FIG. 2. The basic furniture structure 2 has a rear wall 2a, a right-hand side wall 2b and a left-hand side wall 2c. Moreover, the side walls 2b and 2c have crossmembers 8a and 8b according to FIG. 2 running between them, the pushing-out device 6 being fastened on these crossmembers. In FIG. 3, with the drawer 3 fully closed, the pushing-out lever 7 is straightened out or of rectilinear form and in a pivoted-back rest position. The pushing-out device 6 and the crossmembers 8a, 8b advantageously require only a comparatively small amount of installation space in particular in respect of the depth of the piece of furniture 1.
FIGS. 4 and 5 show the pushing-out lever 7 in an inflected form or with an inflection, it being possible for a front angled section of the pushing-out lever 7 to butt with surface-area contact (FIG. 4) or punctiform contact (FIG. 5) against a rear wall 3b of the drawer 3. The pushing-out lever 7 is pivoted somewhat further in FIG. 5 than in FIG. 4, the pivoting movement of the pushing-out lever 7 being effected by a drive unit (not illustrated specifically). By virtue of the pivoting movement of the pushing-out lever 7 and the abutment of the latter against the rear wall 3b of the drawer 3, the drawer 3 is moved a little way in the opening direction out of the closed position, which is illustrated in FIG. 3. The movement of the pushing-out lever 7 does not move the drawer 3 into the fully open position according to FIG. 6. Rather, the pushing-out movement by the pushing-out lever 7 moves the drawer 3 into a partly open position, from which for example an individual can open the drawer 3 further, or close it again, by hand. The movement sequence could also be optimized such that the pushing-out operation alone causes a follow-on movement of the drawer 3 into the fully, or more or less fully, open position.
Following the pushing-out operation, the pushing-out lever 7 is pivoted back immediately, or shortly thereafter, into its rest position again, as shown in FIG. 6. The possibility of inflecting the pushing-out lever in an articulated manner means that the pushing-out lever 7, which is angled during the pushing-out operation, is fully straightened out again, and can be accommodated in a space-saving manner in the basic structure 2, in its rest position according to FIGS. 3 and 6.
The pushing-out device 6 which is shown in FIGS. 3 to 6 and has the crossmembers 8a, 8b and accommodating flanges 9a, 9b is shown in detail in FIGS. 7a to 8e. FIGS. 7a and 8a show, in perspective, the pushing-out device 6, the crossmembers 8a, 8b and the accommodating flanges 9a and 9b in a rest position of the pushing-out lever 7 (see FIG. 7a) and in a partially pivoted position according to FIG. 8a. FIG. 7b shows a section along line A-A from FIG. 7c. Correspondingly, FIG. 8b shows a sectional view along section line B-B from FIG. 8c, and FIG. 8d shows a sectional view through the arrangement according to FIG. 8b along line C-C in FIG. 8e. The pivoting movement of the pushing-out lever 7 is achieved by virtue of a supporting pin 10 on the pushing-out lever 7 interacting with a guide path 11a of a rotating control wheel 11. The control wheel 11 here is driven in rotation via a drive unit (not explained in any more detail), in particular with an electric motor.
FIG. 9 shows a perspective view of the control wheel 11, in a highly schematic state, with the guide path 11a.
An inflection-formed angle a (FIG. 8b) on a side of the pushing-out lever 7 which is directed away from a side which comes into contact with a rear wall of the drawer may have a value of somewhat less than 180 degrees. It is basically possible to have different total lever lengths or positions of the point of inflection along the pushing-out lever 7, as a result of which it is also possible to determine a driven pushing-out movement and an associated total pushing-out distance. The configuration of the guide path 11a can be used to determine the profile of the pushing-out movement over time and/or over an angle of rotation of the control wheel 11.
Two further exemplary embodiments of the pushing-out device 6 are illustrated in FIGS. 10 and 11, the pushing-out device according to FIG. 11 differing from the pushing-out device according to FIG. 10 merely by way of a second drive unit, or a second electric motor 13b, for a gear mechanism 14, e.g. in order thus to provide for a higher level of driving power for the pushing-out operation.
On an abutment side 7a, which comes into contact with a furniture section during the pushing-out operation, the pushing-out lever 7 is of rectilinear design over more or less its entire length, and it is rounded in a front end section.
The pushing-out device 6 according to FIG. 10 has a basic frame 12 on which is accommodated a drive unit in the form of an electric motor 13a with a gear mechanism 14. The gear mechanism 14 serves for transmitting driving action to the control wheel 11, which is provided with an outer toothing formation 11b which interacts with the gear mechanism. A closed guide path 11a is formed further inward, as seen in the radial direction, on the control wheel 11. The guide path 11a serves for guiding and supporting the pushing-out lever 7 via a supporting foot 15 which is angled rigidly on the pushing-out lever and has a rotatably mounted roller 15a provided at its end. Fundamentally rectilinear pushing-out levers are known from the prior art. The roller 15a makes it possible for the supporting foot 15 to roll along the guide path 11a, which slopes up and slopes down in a ramp-like manner in space during the rotation of the control wheel 11, the pushing-out lever being pivoted correspondingly about its pivot axis S and bringing about the pushing-out operation in the process by pushing against the rear wall 3b of the drawer 3. FIGS. 10 and 11 do not show a housing part which performs the function of a front cover and on which the pushing-out lever is also mounted such that it can be pivoted about the axis S.
Individual steps of the operation as a whole are illustrated in FIGS. 12 to 19.
FIG. 11 is used to explain the guide path 11a by way of example, wherein, upon rotation of the control wheel 11 in the clockwise direction, from the fully pivoted position of the pushing-out lever 7 shown, the sections A, B, C and D of the guide path 11a act one after the other as a supporting surface for the supporting roller 15. In this direction of rotation about the axis of rotation R of the control wheel 11, it is thus the case, during one revolution, that section A provides, over an angle of approximately 120 degrees, a uniformly downwardly sloping profile, section B provides, over an angle of approximately 100 degrees, a constantly planar profile with the pushing-out lever 7 pivoted in, section C provides, over an angle of approximately 120 degrees, a uniformly upwardly sloping profile, and section D provides, over an angle of approximately 20 degrees, once again a constantly planar profile. The number of different sections, and the profiles and angle ranges thereof, can be predetermined individually depending on the guide path and/or on the control wheel used. For a corresponding change in the pivoting characteristics, the control wheel can simply be exchanged.
For overload prevention, it is possible, when an in particular predeterminable resistance to the pushing-out movement and/or the pushing-out lever 7 has been reached, for the direction of rotation of the control wheel 11 to be reversed, e.g. when an individual is standing in front of the movable furniture part or is standing in the path over which this furniture part can move during the pushing-out operation.
In order to be fitted on crossmembers, the pushing-out device 6 is provided with, for example, four fitting clips 16 arranged externally in corner regions.
FIG. 12 shows a somewhat more detailed view of a pushing-out device 6 with a pushing-out lever 7 which is located in a pivoted-back position or in a rest position. A front housing section of the pushing-out device 6 is not illustrated in FIG. 12, and this makes it possible to see parts used for the drive transmission from an electric motor 13a to the pushing-out lever 7. Individual components or structural elements, moreover, are shown merely in a highly schematic manner in FIG. 12.
The pushing-out lever 7 is pivoted forward and back about the axis of rotation R via the electric motor 13a and the gear mechanism 14. The gear mechanism 14 and further gear-mechanism or transmission elements 18, 19 and 20 are provided for transmitting the rotary movement to the pushing-out lever 7, and they cause a rotary shaft 21, which is fixed in position on the pushing-out lever 7, to rotate. On its abutment side, on which contact can be made, during the pushing-out operation, with a section of a furniture part which is subjected to the action of the pushing-out lever 7, the pushing-out lever 7 is provided with a rectilinear section G and a section K which is curved or convex at the front and is formed merely in the region of the front half of the length of the pushing-out lever 7. During the pushing-out operation, a position of the point of contact can move in the longitudinal direction of the pushing-out lever 7 essentially in the section K.
FIGS. 13 to 15 show the pushing-out device 6 from FIG. 12, with the front housing section, schematically from above, wherein FIG. 13 shows the state of the pushing-out lever 7 in a rest position or a basic position, and FIGS. 14 and 15 show different pivoting positions of the pushing-out lever 7 during the operation of pushing out a drawer, of which merely part of a rear wall RW is indicated by chain-dotted lines.
In FIG. 13, the rear wall of the drawer butts directly predominantly against the rectilinear section G (FIG. 12) of the pushing-out lever 7, and in particular there is contact here between the rear wall of the drawer and the pushing-out lever 7. Pivoting of the pushing-out lever 7 gives rise to a situation according to FIG. 14, whereas in the in particular fully pivoted state of the pushing-out lever 7 according to FIG. 15 the contact between the rear wall RW of the drawer and the pushing-out lever 7 is just about eliminated. The distance Xmax according to FIG. 15 between the positions of the rear wall RW of the drawer in FIGS. 13 and 15 constitutes the driven pushing-out movement of the drawer. The subsequent movement of the drawer takes place by follow-on, rather than driving, action. Moreover, once the contact between the pushing-out lever 7 and the rear wall of the drawer has been eliminated, the pushing-out lever 7 is pivoted back again into its position which is shown according to FIG. 13. A point of contact between the pushing-out lever 7 and the rear wall RW of the drawer during the pushing-out operation of the drawer moves along the section K in the direction of a front end of the pushing-out lever 7.
FIG. 15 shows, by way of example, a fully pivoted position of the pushing-out lever 7, in which the latter may have, for example, a pivoting angle of approximately 80 to more or less 90 degrees, wherein here, just prior to the contact between the pushing-out lever 7 and the rear wall RW of the drawer being eliminated, the pivoting angle is approximately 70 degrees. The pushing-out device 6 according to FIGS. 13 to 15 may be mounted, for example, in the region of a rear wall of a basic structure (not shown).
A sensor is provided for sensing a movement state or a pivoting movement of the pushing-out lever 7, and this sensor has a sensor part 22a on a basic body of the pushing-out device 6 and a further sensor part 22b on a correspondingly positioned section of the pushing-out lever 7. The sensor parts 22a, 22b may be, in particular, parts of a Hall sensor.
FIGS. 16 and 17 show a further highly schematic exemplary embodiment of a pushing-out lever 7 according to the invention. Also illustrated, highly schematically, in these figures are a drawer 3 and parts of a basic structure 2. The pushing-out lever 7 is shown on its own without any further elements of the pushing-out device. The pushing-out lever 7 can be deformed elastically under load during its pivoting movement (see FIG. 17). It is possible here for the pushing-out lever 7, with the drawer closed according to FIG. 16, to be oriented parallel to a rear wall 3b of the drawer without any significant elastic deformation, if any at all. FIG. 17 shows a pivoting position of the pushing-out lever 7 in which the drawer 3 has been moved a little way out of its closed position via the pushing-out lever 7. The pushing-out lever 7 here has been deformed elastically or bent in certain sections, as a result of which the bending can advantageously change an effective lever length of the force conditions which prevail as a result of the driving action.
FIG. 18 corresponds to an arrangement according to FIG. 16, with an alternative pushing-out lever 7 according to the invention which has multiple inflections. The pushing-out lever 7 according to FIG. 18 has, for example, three points of inflection, and this results in a polygonally running region on the pushing-out lever, with parts of the pushing-out lever 7 spaced apart from the rear wall 3b of the drawer 3 when the latter is closed. This allows the rigid pushing-out lever 7 from FIG. 18 to achieve the advantages of the pushing-out lever according to FIGS. 16 and 17 during the pushing-out operation. The rigid pushing-out lever 7, however, requires somewhat more installation space in the rest position than the elastic pushing-out lever 7.
A further pushing-out lever according to the invention will be explained with reference to FIGS. 19 to 23b. These figures concern a toggle mechanism, which provides for a toggle 24 for pushing out a movable furniture part. The toggle 24 is accommodated on a toggle arrangement 23. The toggle arrangement 23 may be fastened, for example via fitting jaws 25a, 25b, on a furniture-part section, for example on opposite side walls of a basic furniture structure, in the rear region of the latter. The toggle 24 comprises two toggle limbs 26 and 27, which are connected to one another in an articulated manner in their head region. The toggle limb 26 has its end which is opposite to the head section accommodated in a pivotable manner on the fitting jaw 25a. The further toggle limb 27, correspondingly, is accommodated in a likewise pivotable manner on a displaceable carriage component 28.
FIG. 19 shows the toggle 24 in its more or less fully straightened-out position, e.g. when a rear wall of a closed drawer is positioned in front of it. In order to pivot the toggle 24, or to allow a pushing-out operation, an electric motor 13a is fastened on an accommodating component 29. An intermediate component 31 can be moved with guidance via a drive spindle 30, which can be rotated in two directions of rotation with driving action by the electric motor 13a. For this purpose, the drive spindle 30 engages through the intermediate component 31 in a bore which has an internal thread which interacts with an external thread of the drive spindle 30.
FIG. 20 shows the toggle 24 in the pivoted pushing-out position. This is made possible by the driven movement of the intermediate component 31 out of the position which is shown in FIG. 19 into the position which is shown in FIG. 20. The driven displacement of the intermediate component 31 displaces two springs 32a, 32b such that the carriage component 28 is displaced with guidance along two round-profile crossmembers 33a, 33b, which run at a spacing apart from one another between the two fitting jaws 25a, 25b. The distance between the carriage component 28 and the fitting jaw 25a is decreased continuously via the displacement of the springs 32a, 32b, as a result of which the toggle 24 is steplessly angled in an articulated manner and a position which is shown in FIG. 20 can be reached, in which case a drawer can be pushed out. The springs 32a, 32b are strong enough for them to act like rigid elements during normal opening, and for there to be no losses in the transmission of the driving action to the toggle 24, and the springs 32a, 32b yield only when an overload situation, e.g. as will be explained hereinbelow, occurs.
For overload prevention of the toggle 24, or of the toggle arrangement 23, with the toggle limbs 26 and 27 angled in an articulated manner, for example when a force in the direction of the arrow P1 (see FIG. 20) exceeds a limit value, the springs 32a, 32b are designed to be, for example, resiliently compliant and, when a certain spring force is exceeded, they can be compressed such that the overload position of the toggle 24 which is shown in FIG. 21 is reached. The drive spindle 30 and the electric motor 13a thus remain in tact and damage to the toggle arrangement 23 can be ruled out. For overload prevention in a defined position of the intermediate component 31 according, for example, to FIG. 20, the carriage component 28 is displaced in the direction of the intermediate component 31, the springs 32a, 32b being correspondingly shortened by compression. The toggle limbs 26, 27 can thus straighten out again and the toggle 24 is pivoted back and moved, if appropriate, into its more or less straightened-out position according to FIG. 21.
FIGS. 22
a and 22b respectively show a front view and a plan view of the toggle arrangement 23 according to FIG. 19, and FIGS. 23a and 23b show the corresponding views of the toggle arrangement 23 according to FIG. 20. In particular FIGS. 22b and 23b show the comparatively small depth dimensions of the toggle arrangement 23 in the direction transverse to the longitudinal extent of the toggle arrangement 23. This allows the toggle arrangement 23 to be accommodated in a very compact and space-saving manner in a piece of furniture, in particular depthwise in a basic furniture structure. The longitudinal axes of the crossmembers 33a, 33b may be oriented, in particular, approximately parallel to a rear wall of a basic structure. It is thus possible to accommodate, for example, a drawer with a corresponding pushing-out device in a basic furniture structure without the depth of the drawer having to be significantly shortened. The maximum driven pushing-out distance which can be achieved by the toggle arrangement 23 can correspond, at most, approximately to the length of the two toggle limbs 26, 27.
An alternative embodiment of the pushing-out device according to the invention with a bending lever 34 will be explained in more detail with reference to FIGS. 24 to 29, which show a perspective view of the bending lever 34 as seen obliquely from beneath, individual parts of the bending lever 34 having been left out of FIGS. 25, 26 and 29 in order to give a clear view of the bending lever 34. The bending lever 34 comprises two flat housing parts 35a, 35b which are located opposite one another and are fixed in position in relation to one another via connecting pins 36a to 36c. The bending lever 34 also has an elastic lever element 37 and a supporting foot 15 with a roller 15a accommodated in a rotatable manner at its end. The supporting foot 15 and the roller 15a serve to support the bending lever 34 on a guide path of a corresponding control element in the manner as has been explained in more detail, for example, in FIGS. 10 and 11.
The lever element 37 has, at its front end, a bent-over abutment section 37a which, during the pivoting operation, can come into abutment with a mating section, for example with a rear wall of a drawer. At its end positioned opposite the abutment section 37a, the lever element 37, having been bent over, is guided back a little and accommodated between the housing parts 35a, 35b. The bent-over end of the lever element 37 has supported on it an angled plate 38 of the supporting foot (see FIGS. 25 and 26). If the bending lever 34, which can be pivoted with driving action, is then pivoted, during a pushing-out operation, for example about a pivot axis which coincides, for example, with the longitudinal axis of the connecting pin 36a, this can result in that arrangement of the bending lever 34 which is shown in FIG. 27. The lever element 37 here has been deformed elastically under load for example by abutment against a rear wall of the drawer which is to be pushed out. The supporting foot 15 here is oriented approximately at right angles to longitudinal edges of the housing parts 35a, 35b. The extent to which the lever element 37 is bent depends on the force in the bending direction to which the lever element 37 is subjected and/or on the mass which is to be moved during the pushing-out operation of the movable furniture part. FIG. 27 shows the bending of the lever element 37 during the operation of pushing out, for example, a comparatively heavy furniture drawer (not illustrated).
In FIG. 28, an overload-prevention means of the bending lever 34 is active, in the case of which the supporting foot 15, which is accommodated in a pivotable manner between the housing parts 35a, 35b, has been swung away from the position according to FIG. 27. As a result, an effective supporting height provided by the supporting foot 15 is abruptly reduced to a significant extent and the loading to which the bending lever 34 is subjected, or the force acting on the lever element 37, is reduced. For example it is possible, in the position according to FIG. 27, for a supporting distance L1 between a bearing side of the roller 15a and an imaginary longitudinal axis of the housing parts 35a, 35b to be reduced to a supporting height L2 by virtue of the supporting foot 15 being swung away.
To give an understanding of the overload-prevention means according to FIG. 28, FIG. 29 shows, with the lever element 37 illustrated in a cut-away state and the housing part 35a left out, the interaction between the plate 38 and the bent-over end of the lever element 37. If a maximum loading to which the lever element 37 according to FIG. 27 is subjected is exceeded, the supporting foot 15, which is secured with the front end of its plate 38 supported on the bent-over end of the lever element 37, can swivel away, by elastic compliance of the bent-over end of the lever element 37 according to FIG. 27, into the overload position of the supporting foot 15 according to FIGS. 28 and 29, the swiveling-away action being possible as a result of the supporting foot 15 being mounted for rotation about the longitudinal axis of the connecting pin 36c (see FIG. 24).
FIGS. 30 to 32 illustrate the bending lever 34 as part of a highly schematically shown pushing-out device 6 (not true to scale and, in particular, with a drive unit left out) in the installed state in a piece of furniture 1, or a rear wall 2a of a basic furniture structure 2, and interacting with a drawer 3 accommodated in a displaceable manner therein. To illustrate the relationships to better effect, only a bottom part of a front portion 3a of the drawer 3 has been shown.
The pushing-out device 6 is provided with a control wheel 11, as has already been explained in more detail above, in order to pivot the bending lever 34. FIG. 30 shows the operation of the drawer 3 being pushed out by means of the bending lever 34, the drawer 3 having only a light load, if any at all, and the lever element 37 is thus subjected to virtually no elastic deformation, or none at all, during the pushing-out operation. The drawer 3 according to FIG. 30 is pushed out with driving action in the forward direction according to arrow P2.
FIGS. 31 and 32 show a two-stage overload-prevention mechanism of the bending lever 34. If for example the drawer 3, as it is pushed out forward according to FIG. 30, is subjected to a predetermined force from the outside in the direction of the arrow P3, in which case the drawer 3 is moved toward the basic furniture structure in direction P3, it is possible, in a first overload-prevention stage, for the lever element 37 to be bent back correspondingly and for the drawer to move some way into the basic structure 2 (FIG. 31) until the position from FIG. 32, with the drawer 3 closed, is reached, with the second overload-prevention stage triggered, where, in addition to the lever element 37 being bent, the supporting foot 15 is swiveled away. The drawer 3 is then located in a closed position in relation to the basic furniture structure 2. In the case of the overload-prevention means, the supporting foot 15 can pivot away, as it were, from the guide path of the control wheel 11. In principle, the control wheel 11 can then be rotated into a position which corresponds to the closed position of the drawer 3, as a result of which the supporting foot 15 can pass into its approximately right-angled position again and the lever element 37 is rectilinear again, which is shown in FIG. 33.
FIGS. 34 and 34
a show a situation in which a heavy drawer 3, or one with a heavy load, is pushed out by means of the bending lever 34 corresponding to FIG. 30. The heavy loading is symbolized by a weight element in the drawer 3. The bending lever 34 or the lever element 37 bends elastically rearward under the comparatively heavy load of the drawer 3 which is to be pushed out, and this is clear in particular in FIG. 34a, which shows an enlarged detail of FIG. 34.
FIGS. 35 and 35
a, with an enlarged detail of FIG. 35, show the overload-prevention means which is active for the drawer 3 with a heavy load. The arrangement formed here is one which is identical to the arrangement according to FIG. 32.
FIGS. 36 and 37 each show a schematic diagram, in side view, of two different pushing-out devices 6 during the pushing-out operation of a drawer 3, a basic furniture structure which accommodates the drawer 3 not being illustrated. The pushing-out devices 6 according to FIGS. 36 and 37 are shown in highly schematic form and are not true to scale. The pushing-out devices 6 can be fitted, for example, on a rear wall of the basic furniture structure.
An elastically deformable part 40 of the pushing-out lever 7 butts against the rear wall 3b of the drawer 3, the elastic part 40 acting on a rigid part 39 of the pushing-out lever 7. The pushing-out lever 7 can be pivoted about a pivot axis S via a cam plate 42 which can be moved with driving action via a drive unit. Other parts in particular of the pushing-out device 6, for example the drive unit, are not illustrated. As the cam plate 42 is driven in rotation about the eccentrically positioned axis of rotation R, a roller 15a on a supporting foot 15 of the rigid part 39 is supported on an encircling or closed guide path 42a, which is formed by a radially outer narrow side of the cam plate 42. The rotation of the cam plate 42, in this case for example in the clockwise direction, pivots the rigid part 39 of the pushing-out lever 7 and, along therewith, an elastic part 40 of the pushing-out lever 7. The elastic part 40 here pushes against the rear wall 3b of the drawer 3, which is thus pushed out. The pivoting movement of the pushing-out lever 7 can be determined by the sustained support of the supporting foot 15, via the roller 15a, on the guide section which is guided in rotation past the same, or the guide path 42a of the cam plate 42. This gives rise in particular to the pushing-out lever 7 pivoting uniformly as it pushes against the rear wall 3b and pivoting back comparatively quickly following the actual pushing-out operation. The guide path 42a may be formed in various ways, for example, as illustrated, from two more or less rectilinear sections which are connected to one another via two curved sections, the axis of rotation R being located relatively far outward in the vicinity of a transition from a rectilinear section to a curved section.
An alternative embodiment of a pushing-out lever in a position according to FIG. 36 is shown in FIG. 37, in which the pushing-out lever 7, in comparison with the pushing-out lever from FIG. 36, is configured without any elastic part and with the rigid part extended, an inflection 41 being present on the pushing-out lever 7. The pivoting movement is transmitted to the pushing-out lever 7, corresponding to FIG. 36, via a cam plate 42. The inflection 41 may be such that, during the pushing-out operation, the angle of inflection formed by the inflection 41 does not change significantly or can change, for example, elastically over a definable range.
LIST OF DESIGNATIONS
1 Piece of furniture
2 Basic structure
2
a Rear wall
2
b Side wall
2
c Side wall
3 Drawer
3
a Front portion
3
b Rear wall
4 Pull-out guide
5 Front gap
6 Pushing-out device
7 Pushing-out lever
7
a Abutment side
8
a Crossmember
8
b Crossmember
9
a Accommodating flange
9
b Accommodating flange
10 Supporting pin
11 Control wheel
11
a Guide path
11
b Outer toothing formation
12 Basic frame
13
a Electric motor
13
b Electric motor
14 Gear mechanism
15 Supporting foot
15
a Roller
16 Fitting clip
17 Bearing element
18 Transmission element
19 Transmission element
20 Transmission element
21 Rotary shaft
22
a Sensor part
22
b Sensor part
23 Toggle arrangement
24 Toggle
25
a Fitting jaw
25
b Fitting jaw
26 Toggle limb
27 Toggle limb
28 Carriage component
29 Accommodating component
30 Drive spindle
31 Intermediate component
32
a Spring
32
b Spring
33
a Crossmember
33
b Crossmember
34 Bending lever
35
a Housing part
35
b Housing part
36
a Connecting pin
36
b Connecting pin
36
c Connecting pin
37 Lever element
37
a Abutment section
38 Plate
39 Rigid part
40 Elastic part
41 Inflection
42 Cam plate
42
a Guide path
Patent Application
20100084954
