EP0775457A1 - Furniture having variable geometry - Google Patents

Abstract

The rocking chair has a cross member (30) giving a defined linkage gap which is not equal to the linkage point at the seat (16). On a relative movement of the legs (22,28), to each other, a rocking movement is applied, where the angular setting of the seat (16) constantly shifts in relation to the floor (12). A spring system at the moving frame (14) can move the front and back legs (22,28) in a centre position between the two end positions.

Description

The invention relates to movement furniture.

Movement furniture is a piece of furniture whose usable surface, for example a seat or work surface, which is formed on a useful element, can be displaced relative to the floor on which the movable furniture stands. In rocking chairs and cradles, for example, the position of the seat or lying surface can be changed in that a rigid frame having a curved skid slips and rolls on this skid. However, slipping causes the piece of furniture to move across the floor when rocking. In addition, runners attached to a chair protrude far from the chair in order to ensure sufficient security against overturning. They not only require a large footprint, but also stand in the way of stumbling blocks.

The location of a usable area can also be used as an alternative to the described rocking chairs with a movement frame to be changed. A movement chair with an adjustable movement frame is known from DE-PS 369 907. The movement frame of this movement chair, which carries a seat shell as a substantially flat useful element, has a front and a rear pair of legs, each of which is articulated to the seat shell at articulation points. Two coupling rods arranged as struts underneath the seat shell connect the front legs to the rear legs, the coupling rods engaging in an articulated manner on the legs. The distance between the coupling points of the coupling rods is equal to the distance of the articulation points and the distance of the front coupling points to the front articulation points is equal to the distance of the rear coupling points to the rear articulation points, so that the frame describes the shape of a parallelogram in a side view. A movement of the pairs of legs in relation to one another, during which the angles between the pairs of legs and the seat surface or the coupling rods change, the seat surface is displaced relative to the floor while maintaining its angular position.

The invention has for its object to provide a piece of furniture available that takes up only a small area, that does not migrate when a rocking movement is carried out and that there are no dangers associated with its frame.

This object is achieved according to the invention with the features of patent claim 1.

According to the invention, the coupling distance defined by the strut is not equal to the distance of the articulation points of the legs on the utility element. As a result, the movement frame made of legs and bracing describes an irregular square. The useful element arranged on one of the sides of the square therefore experiences a rocking movement when the legs move relative to one another. During this rocking movement, the angular position of the useful element relative to the floor changes. For example, if the movement furniture is a rocking chair, a person sitting on the seat of the rocking chair is subjected to a rocking movement by a movement of the frame. While the frame positions the useful element in such a way that it is inclined particularly steeply with respect to the ground when it moves into one of its end positions, it is in a central position of the legs in a position in which the useful element extends essentially parallel to the ground. The position of the movement furniture on the floor does not change because the legs are only pivoted, but not moved.

The fact that with each leg the point of contact on the floor, the articulation point of the strut and the articulation point on the useful element are essentially on a straight line ensures that the movement furniture does not move on the floor during the rocking movement. The point of contact on the floor only carries out very small horizontal movements, which do not lead to displacements of the movement furniture.

In order to ensure stability, the legs can be provided with a wide foot. It is also possible to design the legs as plate or U elements or to provide a pair of front and rear legs.

A spring arrangement is preferably provided on the frame, which moves the front and rear legs to the middle position lying between the end positions. The spring arrangement causes the legs of the frame to move from any position into the central position, provided that no external forces act, so that the useful element, for example the seat or lying surface, is easily accessible. The spring arrangement also allows the movement furniture to be imparted a pendulum movement by a one-time or recurring deflection, so that the useful element oscillates like a swing.

The spring arrangement can be arranged between the front and rear legs or between one of the legs and the strut. However, it preferably engages the useful element, so that when the useful element is removed from the frame, the spring arrangement is released at the same time. As a result, the movement frame and the useful element are easy to store. The spring arrangement can have a torsion spring, in particular a rubber-elastic spring element, whereby a small size can be achieved.

A damper arrangement can be provided on the movement frame, which brakes the movements of the legs with respect to the useful element. Such a damper arrangement prevents the movement furniture from rocking excessively long after a single push.

With a locking arrangement arranged on the movement frame, the relative position of the useful element with respect to the movement frame, and thus with respect to the floor, can be determined. This makes it possible to move the furniture, For example, to set a movement chair in a position that is particularly comfortable for the user, so that the seating comfort is increased.

A particularly simple construction of the locking arrangement results when a brake is provided on the frame, the first brake element of which is connected to the moving frame and the second brake element of which is connected to the useful element. The brake elements, which are preferably disc-like, are fixed in their mutual position with a clamping device, for example a type of screw clamp or a clamping screw.

The movement furniture is preferably a rocking chair in which the useful element is a seat shell. A backrest, which can be formed in one piece with the seat shell, is preferably arranged on such a seat shell. It is also possible to provide armrests on the movement chair. The armrests can be connected to the legs of the frame and thereby form the strut. In such an embodiment, the strut is then arranged above the useful element. Instead of two legs with a separate coupling rod between the front and rear legs, it is also possible to use an approximately U-shaped element in which the upstanding legs form the legs. Foot areas or feet can be arranged on the web connecting the upstanding legs. In order to ensure that the legs can be swiveled, the transition from the web to the legs is made of bent wood.

The movement furniture can also be designed as a cradle or as a writing and drawing table for children.

In the case of a design as a writing and drawing table for children, a locking arrangement is expedient in order to be able to use the movement and adjustment possibility of the movement furniture without having to put up with a swing movement which is unsuitable in this case.

Fig. 1

einen Bewegungsstuhl in einer Seitenansicht,

Fig. 2

einen Schnitt durch den Bewegungsstuhl in Fig. 1 gemäß der Linie II-II in Fig. 1,

Fig. 3

einen Ausschnitt aus Fig. 2, der eine Federanordnung zeigt,

Fig. 4

einen Schnitt durch den Bewegungsstuhl in Fig. 1 gemäß der Linie IV-IV in Fig. 1,

Fig. 5

den Bewegungsstuhl in Fig. 1 in vereinfachter Darstellung in einer Mittellage,

Fig. 6

den Bewegungsstuhl in Fig. 1 in vereinfachter Darstellung in einer ersten Endlage,

Fig. 7

den Bewegungsstuhl in Fig. 1 in vereinfachter Darstellung in einer zweiten Endlage,

Fig. 8

eine zweite Ausführungsform eines Bewegungsstuhls mit einer Koppelstange aus Federstahl im Schnitt,

Fig. 9

einen Ausschnitt aus Fig. 8,

Fig. 10

einen Schnitt durch den Bewegungsstuhl in Fig. 8 gemäß der Linie X-X,

Fig. 11

eine Koppelstange aus Federstahl zur Verwendung bei einem Bewegungsstuhl gemäß der zweiten Ausführungsform in perspektivischer Darstellung,

Fig. 12

ein drittes Ausführungsbeispiel des Bewegungsmöbels,

Fig. 13

eine Einzelheit des Ausführungsbeispiels nach Fig. 12,

Fig. 14

eine Seitenansicht der Drehfeder,

Fig. 15

eine Rückansicht des Bewegungsmöbels zur Verdeutlichung der Funktion des Zugelements, und

Fig. 16

ein viertes Ausführungsbeispiel.

Further advantageous refinements and developments of the invention result from the subclaims and from the drawing in connection with the description. In the drawing, which relates to a particularly preferred embodiment of the moving furniture, show:

Fig. 1

a movement chair in a side view,

Fig. 2

2 shows a section through the movement chair in FIG. 1 along the line II-II in FIG. 1,

Fig. 3

2 shows a detail of a spring arrangement,

Fig. 4

2 shows a section through the movement chair in FIG. 1 along the line IV-IV in FIG. 1,

Fig. 5

1 in a simplified representation in a central position,

Fig. 6

1 in a simplified representation in a first end position,

Fig. 7

1 in a simplified representation in a second end position,

Fig. 8

a second embodiment of a movement chair with a coupling rod made of spring steel in section,

Fig. 9

8 shows a detail from FIG. 8,

Fig. 10

8 shows a section through the movement chair in FIG. 8 along the line XX,

Fig. 11

a coupling rod made of spring steel for use in a movement chair according to the second embodiment in a perspective view,

Fig. 12

a third embodiment of the movement furniture,

Fig. 13

a detail of the embodiment of FIG. 12,

Fig. 14

a side view of the torsion spring,

Fig. 15

a rear view of the moving furniture to illustrate the function of the tension element, and

Fig. 16

a fourth embodiment.

1 shows, as a preferred embodiment of a piece of movement furniture according to the invention, a movement chair 10 which has a movement frame 14 set up on the floor 12 and a useful element 16 carried by the movement frame 14. The useful element 16 has a seat shell 18, at the rear end of which a backrest 20 is integrally formed.

The movement frame 14 carrying the seat shell 18 has a first front leg 22 and a second front leg 24, which are connected via a cross member 26 (FIG. 2) and form a U-shaped front support element which is essentially open at the bottom. In addition, the movement frame 14 has a first rear leg 28 which, together with a second rear leg and a cross member, forms a second substantially U-shaped rear support element.

The two front legs 22, 24 are connected to the two rear legs 28 via a strut 30 which has a first coupling rod 32 and a second coupling rod 34. The two coupling rods 32, 34 each connect a front leg to a rear leg, the coupling rods engaging on the front legs 22, 24 on first pivot pins 36 and on the rear legs 28 on second pivot pins 38. The pivot pins 36, 38 engage in rotary openings of the first or second coupling rod 32, 34, the center-to-center distance of the rotating openings defining the distance between the coupling points on the first and second coupling rod, respectively.

In order to ensure that the movement frame 14 can be moved, the front and rear legs 22, 24, 28 are not only rotatable with respect to the coupling rods 32, 34, but also with respect to the seat shell 18 in each case. This rotatability is defined by four swivel joints 40, which on the Seat shell 18 are arranged and define at this articulation points for the legs 22,24,28. The swivel joints 40 connect the seat shell 18 to the cross bars of the front and rear support elements. The swivel joints 40, one of which is shown in detail in FIG. 3 is shown, each have two mounting blocks 42 on the seat shell side and one bearing block 44 on the frame side. The mounting blocks 42 are glued and / or screwed to the seat shell 18 and hold a bearing pin 46 passing through both mounting blocks 42. The bearing pin 46 defines an axis of rotation 48 around which the bearing block 44, which has a bearing opening 50 for the bearing pin 46 to pass through , is pivotable.

The length of the front two legs 22, 24 is equal to the length of the rear two legs 28, and the distance between the points of engagement for the swivel joints 40 and the first and second pivot pins 36, 38 is also the same. As a result of this and due to the different distance between the articulation points and the coupling distance, the movement frame 14 describes a trapezoid in every position in which the seat shell always runs parallel to the coupling rods. In their central position (FIGS. 1 and 5), the front and rear legs 22, 24, 28 together with the coupling rods 32, 34 and the seat shell 18 describe a trapezoid in a side view, in which the seat shell 18 runs parallel to the coupling rods and the front and rear legs 22, 24, 28 have an equal but opposite inclination to the floor 12. In order to limit the rotatability of the legs 22, 24, 28 with respect to the seat shell 18, end stops are provided.

A torsion spring 52 made of rubber-elastic material is arranged between one of the fastening blocks 42 and the bearing block 44. The torsion spring is provided with a central circular opening Rotating body and with one end face glued to the mounting block 42 and with its other end face 56 to the bearing block 44. While forces acting on the seat shell 18 are introduced into the movement frame 14 via the fastening blocks 42, the bearing pin 46 and the bearing block 44, the torsion spring 52 serves only as a restoring element when the legs 22, 24, 28 of the seat shell 18 are rotated. With such a rotation (FIGS. 6, 7), an internal tension is built up in the torsion spring 52, which moves the fastening block 42 and the bearing block 44 back into their central position (FIG. 5).

A brake 58 arranged as a locking arrangement between the movement frame 14 and the seat shell 18 serves to fix the relative position of the legs 22, 24, 28 to one another and relative to the seat shell 18. The brake 58, which is shown in section in FIG. 4, has an essentially U-shaped bracket 60 connected to the seat shell 18, one leg of the bracket 60 forming a flat, disk-like first braking element 62. The bracket 60 of the brake 58 is connected to the seat shell 18 in such a way that it ensures all-round guidance for a second brake element 64, which is connected to the frame and is a flat profile. The second brake element 64 engages on the cross member of the rear pair of legs, the connection of the second brake element 64 and the rear cross member allowing the second brake element 64 to rotate relative to the rear pair of legs.

In order to fix the second brake element 64 with respect to the first brake element 62, a thread 66 is provided in the bracket 60 for a clamping screw 68, with which the second brake element 64 can be pressed against the first brake element 62. By tightening the clamping screw 68, the distance between the rear cross member and the bracket 60 fastened to the seat shell 18 is fixed. Since the distances between the attachment point of the first brake element 62 and the rear rotary joints 40 and the distance between the rear rotary joints 40 and the point of application of the second brake element 64 are also fixed, movement of the movement frame 14 is then no longer possible. As an alternative to the brake described, various locking devices, which have rastered disks and prevent the rotation of the rotary joints 40, are also possible as locking arrangements.

A rocking movement of the movement chair 10 is shown in the simplified illustrations in FIGS. 5-7 clarifies. 5 shows the movement chair 10 in a position in which the legs 22, 24, 28 are each in a central position. In this position, the seat shell 18 and the strut 30 run essentially horizontally and parallel to the floor. If, as shown in FIG. 6, the backrest 20 is pushed backwards according to the arrow A, the movement frame 14 is distorted, so that the seat pan 18 is rotated clockwise with respect to the floor 12 and takes an inclined position with respect to the floor 12. During this movement, the front legs 22, 24 are rotated in the counterclockwise direction in such a way that they are rotated from their position which is inclined slightly backwards in the central position into a position substantially perpendicular to the floor 12. The two rear legs 28 are also rotated, but the original inclination of the two rear legs 28 changes reinforced towards the front. With the twisting of the legs 22, 24, 28, the front pivot joints 40 are raised relative to the floor 12, whereas the rear pivot joints 40 are lowered.

FIG. 7 shows the movement chair in a second end position, in which the seat shell 18 has an inclination opposite to the end position shown in FIG. 6. In this end position, the movement frame 14 is distorted in such a way that the rear legs 28 run essentially perpendicular to the floor 12 and the front legs 22, 24 have a greater inclination to the rear than the central position shown in FIG. 5. So when rocking backwards, the upper body tilts forward, whereas when rocking forward, the upper body tilts backwards.

By exercising a one-time or recurring force that is directed essentially parallel to the floor 12, the movement chair 10 can be excited to rock. During this rocking movement, the seat pan 18 passes through different angles of inclination with respect to the floor 12, so that a person sitting on the movement chair 10 experiences a rocking movement. However, since there is no rolling movement during this weighing, for example on the runners of a conventional rocking chair, the movement chair 10 remains stationary and does not move over the floor 12.

FIG. 8 shows a second embodiment of a movement chair 110, which essentially corresponds to the movement chair 10 according to FIGS. 1-7 corresponds. Parts of the movement chair 110 according to the second embodiment, which correspond to parts of the movement chair 10, are therefore provided with reference numerals provided, which are increased in the 100. To avoid repetitions, the description of the corresponding parts is based on the description of FIGS. 1-7 referenced.

The movement chair 110 according to FIG. 8 differs from the movement chair 10 according to FIG. 1 in the design of the coupling rods 132. These coupling rods 132, which each connect a front leg 122 to a rear leg 128, consist of an approximately 8 mm thick, Cross section of circular spring steel. The coupling rods 132 each have a first bend 172 and a second bend 174 at their two end regions 170. At the first bend 172, the ends of the spring steel are each bent through 90 ° in the same direction, so that the angled spring steel pieces form torsion sections 176 which are approximately 40 to 45 mm long. Following these torsion sections 176, the spring steel is angled downward by approximately 90 °, so that lever sections 178 are formed. These lever sections 178 lie in a common plane, but have an angular position with respect to one another which corresponds to the angular position of the legs 122, 128 of the movement chair 110 in its central position.

The coupling rods 132 made of spring steel not only prevent the legs 122, 128 from moving apart on the movement chair 110, but also pretension the frame 114 into a central position. For this purpose, grooves 180 are milled into the legs 122, 128 along the legs 122, 128, into which the coupling rods 132 with their lever sections 178 are inserted. The lever sections 178 run parallel to the legs 122, 128 and are prevented from falling out by one in the respective longitudinal one Groove 180 inserted wedge-like locking piece 182 secured. The torsion sections 176 extend transversely to the longitudinal extent of the legs 122, 128 and form a hinge for a pull section 184 of the coupling rod 132 in question relative to the respective leg 122, 128, so that the angular position of the respective leg 122, 128 relative to the pull section 184 of the coupling rod 132 can be changed. With such a change in the angular position of a leg 122, 128 relative to the pull section 184 of a coupling rod 130, the torsion section 176 is twisted, so that the coupling rod 132 exerts a restoring force via its lever sections 178 and its pull section 184. The function of the movement chair 110 corresponds to the function of the movement chair according to FIGS. 1-7.

The movement chair according to the embodiment of FIGS. 12-15 is formed essentially in the same way as the first embodiment. The front legs 22 are connected to one another by a cross bar 70 which is fastened under the seat shell 18 with two swivel joints 40. A torsion spring 71, which consists of a bent wire, the two end legs 72 of which are inserted into holes in the cross bar 70, engages in the center of the cross bar 70. The end legs 72 are connected by torsion sections 73 bent at right angles to a loop 74 which extends at right angles from the torsion sections 73. The loop 74 lies flat under the seat 18 and is fixed there by a tab 75 fastened to the underside of the seat shell. When the front legs 22 are pivoted, the torsion spring 71 strives to drive the legs 22 back into the rest position according to FIG. 12.

Each of the swivel joints 40 consists of a sandwich package of two plates 76, 77, between which an elastomer layer 78 is arranged, which is normally made of rubber. The upper plate 76 is fastened to the underside of the seat shell 18 with screws 79, while the lower plate 77 is screwed to the crossbar 70 or the relevant leg 22 with a screw 80. The sandwich-like swivel 40 has the advantage that it allows noiseless pivoting movements of the legs.

The movement chair according to the figures 12-15 also has a tension element 81, which consists of a wire bracket, which limits the forward movement and / or backward movement of the seat shell 18. 15, the tension element 81 has two end sections 82, which are fastened to the rear legs 28, approximately at the same height as the struts 30. The central part of the tension element 81 protrudes obliquely upwards according to FIG. 12 and extends through a longitudinal guide 83 which is fastened under the seat shell 18 in the central region of the seat surface. This longitudinal guide 83 allows a forward and backward limited movement of the central area of the tension element 81 with respect to the seat surface 18. It acts as a stop element to limit the rocking movement forward and / or backward. The longitudinal guide can also be designed as a drive element for determining the respective positions of the seat shell. In this case, a corresponding actuating element is provided.

The embodiment of Fig. 16 corresponds to the previous embodiment. In addition, armrests 85 are provided, each with one of the front Legs 22 are firmly connected. The armrests 85 are formed here in one piece with the legs 22 and they protrude in an arc from the end of a leg 22 in the direction of the backrest 20. The armrest 85 forms a cantilever which projects freely from the leg 22. To a certain extent, it acts as a lever on which the seated person can grip to swing. Alternatively, it is also possible to attach the armrest 85 not to the front legs 22 but to the rear legs 28.

Claims (14)

Movement furniture with a movement frame (14) which can be set up on the floor (12) and to which a useful element (16) is fastened, which, for example, forms a seat or work surface, the movement frame (14) having at least one front leg (22, 24) and has at least one rear leg (28) which are each connected via pivot points (40) defining pivot points to the useful element (16) and to each other by a strut (30), the distance between the coupling points of the strut (30) defining the coupling distance,
characterized,
that the coupling distance defined by the strut (30) is not equal to the distance of the articulation points on the useful element (16), so that the useful element (16) experiences a rocking movement when the legs (22, 24, 28) move relative to each other, in which the angular position of the useful element (16) with respect to the floor (12) changes constantly, with each leg (22, 24) the point of contact on the floor, the articulation point of the strut (30) and the articulation point on the useful element lying essentially on a straight line. Movement furniture according to claim 1, characterized in that the movement frame (14) has a spring arrangement which moves the front and rear legs (22, 24, 28) in each case into a central position lying between two end positions. Movement furniture according to claim 2, characterized in that the spring arrangement acts on the useful element (16). Movement furniture according to claim 2 or 3, characterized in that the spring arrangement has at least one torsion spring (52, 71). Movement furniture according to claim 4, characterized in that the at least one torsion spring (52) has a rubber-elastic spring element. Movement furniture according to claim 1 or 2, characterized in that the spring arrangement has a torsion spring integrated in the strut (130). Movement furniture according to claim 6, characterized in that the strut (130) has two coupling rods (132), each of which has a pull section (184), two torsion sections (176) made of spring steel and running essentially in a direction perpendicular to the pull section (184) has two lever sections (178) lying in a common plane substantially perpendicular to the plane of the torsion sections (176). Movement furniture according to one of claims 1-7, characterized in that the movement frame (14) has a damper arrangement which brakes the movements of the legs (22, 24, 28) with respect to the useful element (16). Movement furniture according to one of claims 1-8, characterized in that a locking arrangement is provided on the movement frame (14) with which the relative position of the useful element (16) relative to the movement frame (14) can be determined. Movement furniture according to claim 9, characterized in that the locking arrangement has a brake (58) with a first brake element (62) connected to the movement frame (14) and a second brake element (64) connected with the useful element (16), the relative position the braking elements (62, 64) can be fixed with a clamping device. Movement furniture according to claim 4, characterized in that the torsion spring (71) acts on a crossbar (70) which connects the upper ends of two front legs (22) or two rear legs (28) and is supported on the useful element (16) . Movement furniture according to one of claims 1 to 11, characterized in that at least one of the rotary joints (40) has a sandwich package of two plates (76, 77) and an elastomer layer (78) arranged between them, one plate (76) on the useful element (16) and the other plate (77) is attached to the respective leg (22, 28) or a crossbar (70) connected to the leg. Movement furniture according to one of claims 1 to 12, characterized in that a pulling element (81) is fastened to the front or rear legs (22, 28) and engages in a longitudinal guide (83) of the useful element (16) in order to prevent the rocking movement of the Limit useful element. Movement furniture according to one of claims 1 to 13, characterized in that the front legs (22) or the rear legs (28) are firmly connected to armrests (85).

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