EP0263442B1 - Chair - Google Patents

Abstract

A chair is disclosed comprising in combination four legs, seat, backrest and a hidden central underframe that supports the seat. Each leg of the chair comprises two leg rods defining a central recess for receiving an arm projecting outwardly from the hidden central underframe.

Description

The invention relates to a chair with four legs, a seat, a backrest, a frame part connecting the legs and supporting the seat, the backrest being fastened to the rear legs projecting upwards beyond the seat.

There are many chair designs. Common to all is that at least legs, seat and backrest as well as connecting means are provided. There are many options for the design, which are based on the one hand on the design, on the other hand on the user wishes and above all on the manufacturing options and the like.

In a chair known from DE-A-32 24 812, the leg frame is bent from specially profiled tubes. Connected parts attached to it carry the seat and the backrest. This construction, which is advantageous in terms of manufacturing technology for the design that is possible, is tied to the use of profiled bars for the entire leg frame, which, if appropriate with appropriate inserts, also offer sufficient stability in the bending area. The overall shape is determined by the leg frame, but also limited.

Other chairs have straight upright legs, which can be extended to support the backrest if necessary, extending beyond the seat surface at the rear. These are mostly made of wood, but also made of square steel tubes and the like. Chairs constructed with light metal castings have V-shaped legs on the sides. Another construction known from uses of the applicant provides a horizontal support element design with sleeves standing vertically at the corners, into which round leg bars are inserted from below and where armrest and backrest supports can be inserted from above, if necessary. Each of these and many other solutions is largely firmly connected with very special materials, manufacturing processes and a corresponding appearance, whereby the coloring options and the material combinations also largely depend on the design concept of the chair.

The invention has for its object to propose a chair in which straight semifinished elements, such as metal tubes or wooden rods, can be used for the legs, which allow different combinations depending on the stability needs and the design requirements and the rods can be made continuously, however interact with a suitable support structure for connecting the legs and carrying the seat, and which enables favorable manufacturing conditions in series production even with different colors or material combinations.

• vier Beine;
• ein Sitz ;
• eine Rückenlehne;
• ein die Beine verbindendes, den Sitz tragendes und als inneres Rahmenteil ausgebildetes Zargenteil;
• der Sitz ist im Abstand über dem Zargenteil gehalten;
• die Rückenlehne ist an den hinteren, über den Sitz nach oben hinaus aufragenden Beinen befestigt;
• jedes der Beine ist aus mindestens zwei geraden, zylindrischen, unmittelbar aneinander liegenden Rundstäben gebildet;
• das Zargenteil weist abstehende Bein-Anschluß-Arme auf;
• die Anschluß-Enden der Bein-Anschluß-Arme reichen jeweils in die nach innen weisenden Vertiefungen zwischen den beiden Rundstäben jedes Beines;
• sie sind dort mit den Beinen die auftretenden Stütz-, Biege- und Verdrehkräfte aufnehmend verbunden.

A chair according to the invention has the following features:

• four legs;
• a seat;
• a backrest;
• a frame part connecting the legs, supporting the seat and designed as an inner frame part;
• the seat is held at a distance above the frame part;
• the backrest is attached to the rear legs, which rise above the seat;
• each of the legs is formed from at least two straight, cylindrical, directly adjacent round rods;
• the frame part has projecting leg connection arms;
• the connection ends of the leg connection arms each extend into the inward-pointing recesses between the two round rods of each leg;
• there they are connected with the legs to absorb the supporting, bending and torsional forces.

The straight legs formed from at least two round bars can now run through and by simple Clipping be formed. You do not need to be inserted into corresponding cylindrical sleeves of a frame and connecting part and adapted accordingly. So you are much freer in the choice of design and appearance and can achieve much slimmer legs with great stability thanks to the double round bars. You can now also use materials for the legs, such as those used in bent semifinished legs, for example according to DE-A-32 24 812 or in the rattan chairs made of naturally grown round bars or in chairs made of thin round steel bars, such as those used for coffee house chairs were not suitable. Due to the fact that the connection between the leg and the frame part takes place in the inner area between two round bars, depending on the strength requirements, a length can be chosen for the connection that is independent of the round bar diameter and that even with interesting design variants with straight, multi-bar Legs or round rod legs combined into bundles enable sufficient attachment at the most critical point even with difficult materials, such as thin wooden rods or the like. The fact that the frame part of the usual outer frame construction, which is grooved or tapped into the wooden legs, and provides an inner frame part that has protruding arms, you can choose a free-floating construction for the connection of the legs and the seat and nevertheless has cheap connection options for the forces to be introduced and, above all, functional design freedom for the frame part or frame part elements, depending on whether you want a version in metal, in wood or in wood-composite materials and / or possibly plastics. Depending on the type of connection chosen and the material, you can use different looking materials, for leg parts and / or frame parts and use frame arms and is therefore much freer in terms of the design and design of the chair than in many other constructions and still achieves good stability and inexpensive manufacturing options. The individual parts of the legs can be painted in different colors if desired and only assembled afterwards or made of different materials if the manufacturing options, the manufacturing costs and / or the demands on the design require or make it appear desirable.

In a further advantageous embodiment of the invention, the legs can consist of extruded aluminum tube. "Aluminum tube" also means materials that are not pure aluminum, but also alloys and other equivalent light metals. This feature, which is important for the construction of the invention, can be realized particularly well in such a chair, because extruded aluminum tubes cannot be deformed or cannot be deformed with reasonable effort and, through the choice of the material aluminum or the like, construction principles have to be chosen which are based on the facts of straightness and always take the same cross-section into account. However, if you want to have slim, clear external surfaces that are not interrupted even in the upper end area or flow area near the seat, it makes sense to choose the solution with the frame part with protruding arms that engage between the round bars. A 'frame part' is understood to mean a component which connects the legs, holds together and supports the seat, the support structure of which is not limited to the fact that the "frames" are, as with conventional legs, in the planes determined by the leg axes or close to these planes, but rather that the areas giving stability are formed as upright, flat parts forming a framework.

The round bars can be put together from single bars. In particular for the aluminum tube solution, however, it is expedient if two round tubes are formed as an integral extruded profile. They can be manufactured well in terms of production technology, offer favorable stability properties with a small cross-section and slim appearance, and allow one without further reinforcement to achieve a certain appearance in terms of the overall design and / or to attach an armrest that matches the style of the chair insert the third round bar into the recesses of the two round bars attached to the frame part, which are exposed to the outside and are to be fastened in a suitable manner. The attractively designed exemplary embodiment makes advantage of this possibility in the case of the front legs, wherein according to a further development of the invention the third tube of the front legs can have a pointed outer rib engaging in the recess of the two tubes. On the one hand, this ensures easy, secure installation, and on the other hand, with the help of this interlocking rib-groove construction, stabilization can also be achieved over a longer length, for example by gluing and / or screws.

The leg profile tubes have practical narrow and low protective ribs running lengthways on the outside. These are easy to manufacture using the extrusion process and prevent scratching of the surfaces, especially when the chairs are stacked. The construction according to the invention makes it particularly inexpensive to create stackable chairs.

The leg tube profiles can expediently have longitudinal centering and fastening ribs on the inside. On the one hand, these serve as reinforcement, but above all they allow the components to be securely aligned with one another because of the necessary bevel cuts and the molded parts to be inserted, the molded parts also being able to grip the fastening ribs.

The connection ends of the protruding leg connection arms of the frame part and possibly the backrest can each be made at the outer ends of the tubes, possibly with engagement in the tube ends. However, such solutions only allow very specific designs for the corner connection. It is particularly expedient if the connection is made at a distance below the ends of the leg bars. Suitable connecting elements and / or cover plugs can then be inserted into the ends of the leg bars, which hold together the leg bars which, under the clamping forces of parts to be connected, may be pushed apart. In addition, there is an appealing design in the sense of the design, which also allows the round bars to be cut off or left in inclined and / or curved surfaces. Appropriate foot and / or end cover and / or connecting plugs are allowed to engage in the pipe ends.

The frame part expediently has a rectangular base body with vertical walls, in the corners of which the leg connection arms protrude diagonally. On the other hand, however, a curved and / or ribbed structure can also be provided for this.

The leg connection arms for the front legs are expediently allowed to run in a straight line in the diagonal of the chair. So you can combine two inward and one inlaid rod into an attractive slim but sufficiently stable bundle and let the frame part attack geometrically favorably.

In the rear area, it may be advisable to use round rods which are somewhat thicker in diameter, where these should be one behind the other with respect to the chair side line, so that the rear arms on the frame part up to the connecting plane of the rear legs run diagonally and each have an angled connecting leg in the connecting plane. This leg also runs perpendicular to the connecting plane of the axes of the two round bars and can be easily inserted and connected. The connection ends of the leg connection arms are expediently tapered and chamfered if you want to choose a welded connection for the aluminum construction, so that the weld seam can be made strong and well-bearing, but the outer appearance is not disadvantageous.

For fastening the seat and, if necessary, for accommodating stacking plugs, it can be expedient to provide vertically extending recesses in the corners of the rectangular frame of the frame part. These can preferably have a cylindrical shape. They can be manufactured cheaply with the frame part elements and allow the relevant components to be assembled and fastened by simply plugging them in.

The frame part can be assembled in one piece or from several elements. A casting solution for the entire part is basically possible for the production in aluminum. However, this requires expensive and large molds. A solution that better fits into the overall concept of the chair with extruded aluminum tubular legs, in which the frame part also consists of extruded aluminum elements. Cutting off the entire frame part from a one-piece extruded profile would mean a great deal of effort for the overall profile. More favorable manufacturing, storage and transport conditions result if the frame part with its projecting arms is made up of four sections of two identical extruded profiles, which are cut off according to the height of the frame part. These have in the connection area Expedient slot receptacles and chamfering, if necessary, to insert connecting straps and to enable welding, the connecting straps being used alone or additionally for connection by means of rivets.

The backrest can be attached in many ways. However, it is useful to have the backrest fastened between the two round bars. In the case of the design with light metal extruded profiles, it is practical to incorporate longitudinal slots from above into which tapered flat parts of the preferably curved backrest engage in the insertion area. The pipe ends are then expediently covered by insertion plugs which hold them together and ensure stability. You can bevel the pipe ends and / or their plugs according to the sloping upper boundary line of the backrest. Then you only need relatively short legs and a connection with short lever arms, but thanks to the inclined design for the most part in the middle of the backrest a favorable support of the back of the user is possible even in higher parts.

The chair with extruded aluminum parts is particularly suitable for many applications, especially under hygienic and difficult cleaning conditions. For other applications and in particular for some purchasing and user requests, however, a chair should consist of wood or at least look like it or be designed with wooden outer surfaces. Such a chair can be realized in different ways with the same basic concept as described above. In an advantageous embodiment, the legs are made of interconnected cylindrical solid wood rods. This configuration allows different connections on the frame part, which can be carried out in conventional connection technology. It is particularly expedient, however, that the ends of the projecting arms of the frame part have dovetail-like thickenings which engage in suitably shaped recesses in two adjacent round rods which are inserted and preferably glued to them. This creates a large-area stable connection between the frame part and the leg bars, which can be carried out in a wide variety of suitable woods. For the manufacture and a permanently stable construction, it is expedient if the frame part consists of compression-molded plastic-fiber-wood, to which the outwardly projecting dovetail-like fastening thickenings with a continuous fiber course are molded. Such a solution, which can be realized inexpensively and inexpensively in the new production techniques available on the market, leads to a continuous fiber course from the connection regions of the legs through the corner regions of the frame parts, the fibers being inserted into a corresponding shape, preferably entangled with one another, and provided with resin be pressed into a solid wood composite material component, which is particularly favorable for the special load conditions of cantilever chair structures with frames on the inside of the frame attached to the arms.

The connection between the backrest and the rear legs can be formed in a similar manner with integrally formed thickenings and corresponding receiving recesses on the legs. You can use similar fiber-plastic pressing techniques for parts of the backrest or the entire backrest. However, if you want a backrest made of flat material, for example deformed plywood, you can have it gripped between the two upstanding round bars, similar to the construction described above. Another particularly expedient and stable connection between the backrest and legs formed from two round wooden rods provides that the backrest has on each side a dovetail-shaped, front-connected metal profile which engages in vertically machined slots in the adjacent wooden round rods. Then you can implement a very slim design and still create a stable connection over a long distance at the highly stressed point, which is also simple and safe from a machining point of view.

In order to create the appearance, stability and shape of the rear legs formed from double rods in both stability and design, corresponding front legs, it is expedient to build this from three rods. The third rod of the bundle of the front legs can also be glued to the connection ends of the leg connection arms of the frame part and possibly the other round rods of the leg with recessed, possibly spring-shaped or disc-shaped dowels by means of hidden dowels. This gives you a securely connected front leg made from slender round bars.

However, if you want a more stable construction with the look of real wood, you can also use one Choose a concept in which stable metal rods are surrounded by wooden parts. The round bar solution is particularly suitable for this because no joints appear when the round bars are in contact. For such a solution, a frame part made of metal or molded fiber wood is expediently provided, on the leg connection arms of which a vertically extending flat profile in the rear region and in the region of the front legs a T-profile with the middle leg pointing outwards at 45 ° connected, preferably screwed. The leg length and leg thickness of the flat profile and T-profile are considerably smaller than the diameter of the wooden round bars and the wooden round bars are provided with suitable longitudinal slots, by means of which they are attached to the metal legs. So you have a slim metal support frame, for example made of steel or light metal, over which the slotted wooden rods are stuck. You fully dress this. The wooden sticks expediently protrude above the metal insert. This way it is fully covered and you don't need any special cover caps that catch the eye in terms of shape, but the end grain can be made visible. Here, too, the wooden rods can be cut off or machined at their upper ends in a steeply inclined plane or other curved surface.

The chair concept according to the invention provides a seat which is fastened over the frame part, preferably at a distance. For such, but also for other chair constructions, spacers are expediently provided under the seat, in the lower ends of which threaded holes are provided, by means of which the seat with the interposition of spring elements on the frame part is attached. Then you can allow comfortable, sprung sitting, like office chairs, on a chair of a simple design even if you use only a thin or no padding. Appropriately, one also provides that the spring elements are penetrated by screws, by means of which the spring preload and / or the seat inclination can be adjusted. So on the one hand you can adjust the spring characteristics either during manufacture in the factory or later at the user, but above all you can also adjust the seat angle with simple means by tightening the screws to different degrees and thus achieve individual seating comfort on a simple chair as it did before was customary only with structurally complex upholstery. Rubber pins or blocks or rubber-elastic plastic pins or blocks come into consideration as spring elements. However, you can also use helical compression springs. The heads of the clamping screws are expediently fastened axially immovable in holding holes in the frame part. For this you can use the recesses treated in the front, provided in the corners of the rectangular framework of the frame part. An easy-to-assemble arrangement provides a U-shaped round wire clamp, which engages through transverse bores in the seat-holding recesses and with washers on both sides of the clamp arms, which are penetrated by the screw installed with the head at the bottom, on which the Centered spring element and the screw then engages in a threaded bore of the seat holding element. With such a construction, it is possible to use a seat made of an unpadded hard, washable material, such as molded wood or metal, even for good seating comfort and to provide passage openings for liquids at its deepest points. So you can have a comfortable, attractive chair for Create canteens, cafes, kindergartens, hospitals, doctor's surgeries and the like, which can be washed off as a whole and which can even run off with poured liquids and can be easily cleaned. Because of the spring-loaded mounting of the seat, you can still achieve a level of comfort that can otherwise only be achieved with upholstered chairs.

According to its basic concept, the chair with round bar bundle legs can also be optionally and optionally subsequently provided with armrests, which are preferably characterized by the fact that they have a vertical round bar which is inserted into the recess of each rear leg pointing away from the connection on the frame part and fastened to it and wherein the approximately horizontally extending armrest tube is connected to the vertical round bar, preferably with an oblique bend, and merges at its front end into a vertical front end region, which is followed by a horizontal section bent under the seat, which is preferably fastened to the frame part . Further details, advantages and features and aspects of the invention also emerge from the following description, drawn up with reference to the drawings, and the claims.

Embodiments of the invention are explained below with reference to the drawings.

Fig. 1

Die Schrägansicht schräg von rechts vorn oben auf ein erstes Ausführungsbeispiel eines Stuhles;

Fig. 2

die Vorderansicht des Stuhles nach Fig. 1;

Fig. 3

die Rückansicht des Stuhles nach Fig. 1 und 2;

Fig. 4

die Seitenansicht des Stuhles nach den vorstehenden Figuren;

Fig. 5

die Draufsicht auf den Stuhl nach den vorstehenden Figuren;

Fig. 6

die Unteransicht des Stuhles nach den vorstehenden Figuren;

Fig. 7

einen vergrößerten Querschnitt durch das eine hintere Bein gemäß der Schnittlinie 7-7 in Fig. 1;

Fig. 8

einen vergrößerten Querschnitt durch das eine vordere Bein gemäßt der Schnittlinie 8-8 in Fig.1;

Fig. 9

eine Teildraufsicht auf etwas mehr als die linke Hälfte des Zargenteiles bei abgenommenem Sitz samt Sitzbefestigung und mit Darstellung der Beine im Schnitt, gelegt unmittelbar über dem Zargenteil und in einem von den vorstehenden Figuren abweichenden Maßstab;

Fig. 10

die Teil-Seitenansicht von vorn auf das linke obere Bein mit angeschlossener Rückenlehne, jedoch ausgezogen dargestelltem Zapfen;

Fig. 11

einen Horizontalschnitt längs der Linie 11-11 in Fig. 10 durch das rechte Hinterbein des Stuhles, wobei jedoch der Übersichtlichkeit halber der eingesteckte Teil der Rückenlehne nur strichpunktiert dargestellt ist;

Fig. 12

eine Explosionsdarstellung in Schrägansicht auf die hintere rechte Ecke des Zargenteiles mit Anschluß eines hinteren Beines, wobei jedoch der obere Teil abgeschnitten ist und mit auseinandergenommen dargestellter Befestigung für den Sitz und mit Stapelstützzapfen;

Fig. 13

die Schrägansicht eines weiteren Ausführungsbeispieles eines Stuhles entsprechend Fig. 1, jedoch mit Armlehnen;

Fig. 14

einen vergrößerten Horizontalschnitt längs der Linie 14-14 in Fig. 13;

Fig. 15

eine der Fig. 1 entsprechende Schrägansicht eines weiteren Ausführungsbeispiels eines Stuhles mit Massivholzbeinen;

Fig. 16

einen vergrößerten Horizontalschnitt längs der Linie 16-16 in Fig. 15 durch ein Hinterbein;

Fig. 17

einen vergrößerten Horizontalschnitt längs der Linie 17-17 in Fig. 15 durch ein Vorderbein;

Fig. 18

einen vergrößerten Teil-Horizontalschnitt längs der Linie 18-18 in Fig. 15 durch die Befestigung von Zargenteil und Rundstäben des Hinterbeines, wobei jedoch das Zargenteil ohne Schnittschraffur gezeichnet ist, um den Faserverlauf der Holzfasern übersichtlich darstellen zu können;

Fig. 19

eine Teil-Seitenansicht auf das obere Ende eines Vorderbeines mit dem Bein-Anschluß-Arm, jedoch ohne Sitz und dgl. eines Stuhles nach den Fig. 15 bis 18;

Fig. 20

eine um 90° gedrehte Ansicht des oberen Endes des Beines nach Fig. 19, wobei der Bein-Anschluß-Arm geschnitten ist, jedoch zur Darstellung seiner Fasern auf die Anbringung einer Schnittschraffur verzichtet wurde;

Fig. 21

einen Teil-Horizontalschnitt längs der Linie 21-21 in Fig. 19;

Fig. 22

einen vergrößerten Teil-Horizontalschnitt längs der Linie 21-21 in Fig. 15 durch das rechte Hinterbein nebst Befestigung der Rückenlehne;

Fig. 23

eine Explosionsdarstellung eines weiteren Ausführungsbeispieles für eine Ausgestaltung von Zargenteil und Vorderbein eines Stuhles mit Metalleinlagen in den Holzbeinen;

Fig. 24

eine zur Fig. 23 gehörige Explosionsdarstellung für die Gestaltung eines Hinterbeines mit metallenen Einlegeteilen und Massivholzstäben mit Anschluß am Zargenteil und an der Rückenlehne.

Show it:

Fig. 1

The oblique view obliquely from the top right to a first embodiment of a chair;

Fig. 2

the front view of the chair of Fig. 1;

Fig. 3

the rear view of the chair of Figures 1 and 2.

Fig. 4

the side view of the chair according to the preceding figures;

Fig. 5

the top view of the chair according to the preceding figures;

Fig. 6

the bottom view of the chair according to the preceding figures;

Fig. 7

an enlarged cross section through the one rear leg along the section line 7-7 in Fig. 1;

Fig. 8

an enlarged cross section through the one front leg along the section line 8-8 in Figure 1;

Fig. 9

a partial plan view of slightly more than the left half of the frame part with the seat removed, including the seat attachment and with a representation of the legs in section, placed immediately above the frame part and on a scale different from the previous figures;

Fig. 10

the partial side view from the front of the left upper leg with attached backrest, but the pin is shown in an extended position;

Fig. 11

a horizontal section along the line 11-11 in Figure 10 through the right rear leg of the chair, but for the sake of clarity the inserted part of the backrest is only shown in dash-dotted lines;

Fig. 12

an exploded view in an oblique view of the rear right corner of the frame part with connection of a rear leg, but the upper part is cut off and with the mounting shown disassembled for the seat and with stacking support pins;

Fig. 13

the oblique view of a further embodiment of a chair corresponding to Figure 1, but with armrests.

Fig. 14

an enlarged horizontal section along the line 14-14 in Fig. 13;

Fig. 15

one of FIG 1 corresponding oblique view of another embodiment of a chair with solid wood legs.

Fig. 16

an enlarged horizontal section along the line 16-16 in Figure 15 by a hind leg.

Fig. 17

an enlarged horizontal section along the line 17-17 in Figure 15 by a front leg.

Fig. 18

an enlarged partial horizontal section along the line 18-18 in Figure 15 by the attachment of the frame part and round rods of the rear leg, but the frame part is shown without hatching in order to be able to clearly show the grain of the wood fibers.

Fig. 19

a partial side view of the upper end of a front leg with the leg connection arm, but without a seat and the like. A chair according to FIGS. 15 to 18;

Fig. 20

19, a view rotated by 90 ° of the upper end of the leg according to FIG. 19, the leg connection arm being cut, but to show its fibers no cut hatching has been carried out;

Fig. 21

a partial horizontal section along the line 21-21 in Fig. 19;

Fig. 22

an enlarged partial horizontal section along the line 21-21 in Figure 15 by the right hind leg and attachment of the backrest.

Fig. 23

an exploded view of another embodiment for an embodiment of the frame part and front leg of a chair with metal inserts in the wooden legs;

Fig. 24

23 an exploded view for the design of a rear leg with metal inserts and solid wood rods with connection to the frame part and to the backrest.

The first embodiment of a chair according to the invention is shown in FIGS. 1 to 12. The chair 20 has front legs 21.1 and 21.2 and rear legs 21.3 and 21.4, a frame part 22, a seat 23 and a backrest 24.

Seat 23 and backrest 24 are formed according to the desired profile from correspondingly editable plywood.

The frame part 22 consists of a rectangular frame 25 and protruding leg connection arms 26.1, 26.2, 26.3, 26.4, which together form a unit. Fastening recesses 27, here in the form of cylindrical recesses, for the seat fastening are formed in the inner corners of the frame 25.

In this exemplary embodiment, the manufacture from four frame part elements 22.1, 22.2, 22.3 and 22.4 is selected according to FIGS. 6 and 9. As can be seen from FIG. 6, these are constructed from two identical profile parts, the front profile parts and the rear profile parts each being the same, but being mounted the other way round. The frame profile parts each have frame arms 28 which are at right angles to one another, the thickened ends 29 of which are equipped with connecting slots 30 and chamfered 31 to receive a weld seam 32. As can be seen, tabs 33 with a smooth outer surface fit into the depressions and slots 30. The corresponding legs can, as can be seen and indicated by the axis 34, be riveted. The frame part elements 22.1, 22.2, 22.3 and 22.4 are cut off with the height 44 of extruded profiles correspondingly manufactured as semi-finished products.

The front frame part elements 22.1 and 22.2 have straight leg connection arms 26.1 and 26.2 in the diagonals 46, while the leg connection arms for the rear legs 21.3 and 21.4 run up to the connection plane 40 of the rear legs on the diagonals 46, but there are angled to connecting legs 35. The ends 36 of all four leg connection arms 26 are, as shown in FIG. 9, tapered and chamfered at the extreme end, so that weld seams 37 can be accommodated over a large area, but can hardly be seen.

As can be seen from FIGS. 7 to 9, the legs 21 consist of bundles of round bars, with two adjacent round bars delimiting an inwardly pointing depression 38 and 39 between them. The leg connection arms 26 engage with these tapered ends 36 in these recesses. In this embodiment, the legs 21 are formed from extruded aluminum profile tube and welded with the aid of the weld seams 37. This results in a stable frame welded together from light metal extrusions. The height 44 of the frame part 22 with its leg connection arms 26 can be selected in such a way that the strength requirements take into account the desired design. The pure light metal construction offers plenty of freedom for the visual design, whereby a self-supporting, slim frame can always be realized, on and on which seats and backrests of different types can be attached.

In this exemplary embodiment, the legs are formed from bundles of round rods which have favorable stability properties with little material expenditure and a slim, elegant-looking appearance.

While the rear legs are made up of two round bars, the front legs are made up of three round bars. Both the rear legs and the front legs each have a double-tube pair which is produced in one piece using the extrusion process and is designed in the manner of a twin rifle barrel. In the case of the rear legs, the connecting plane 41 of the axes 43.1 of the round bars 45.1 or 45.2 is perpendicular to the plane 40 which connects the two rear legs, while the connecting plane 42 of the axes 43.2 is related to the round bars 45.3 and 45.4 of the front legs 21.1 and 21.2 adjacent to the frame part the aforementioned planes 40 and 41 run at 45 ° and are perpendicular to the diagonal 46. Both profiles are designed in the same way, but have slightly different diameters 47 and 48. The diameter 48 of the three front tubular round bars 45.3, 45.4, 45.5 is somewhat smaller than the diameter 47 of the tubular round bars 45.1, 45.2 of the rear legs 21.3, 21.4. This results in an optically appropriately coordinated overall impression of the legs, taking into account the stability conditions. In a practical embodiment, the diameter 48 can be, for example, 24 mm, while the diameter 47 is, for example, 27 mm. The round bars 45 designed as double round tubes have on their inner walls 50 opposite longitudinal ribs 51 projecting inwards, which are arranged in planes running perpendicular to the planes 41 and 42. They serve to reinforce and center plugs to be treated below. Constrictions or depressions 38 and 39 are formed between the two tubular round bars 45.1 and 45.2 or 45.3 and 45.4. The tapered ends 36 of the leg connection arms 26 extend in the corresponding areas to the inner depressions 38. The tubular third round rod 45.5 is inserted into the outer recesses 56 of the front legs. This has only one longitudinal rib 51 inside for centering and reinforcement. It has the same outer diameter 48 as the double tubes 45.3 and 45.4 of the front legs 21.1 and 21.2. In the area of the inner rib 51, a tapered outer rib 57 is formed on the outside, which protrudes approximately in the shape of a triangular prism, and extends into the recess 56 fits into the pair of pipes. It is used for stabilization and alignment as well as for gluing and / or screwing.

The outer surfaces 59 of all the round bars 45 are provided with thin, low, preferably semi-cylindrical protective ribs 60 which can be arranged at suitable intervals, for example in planes which form an angle of 45 ° with one another.

As can be seen from the drawings, the legs are continuously formed from one-piece round rods without longitudinal interruption. The leg connection arms 26.3 and 26.4 engage the rear legs 21.3 and 21.4 approximately in the middle, so that there is a suitable seat height. The front legs are designed in a way that not only determines the particularly appealing design, but also is favorable in terms of manufacture and strength, so that their upper limit 62 extends by an amount 63 above the upper edge 64 of the frame part. From there, the two front legs are cut off in planes 65 running obliquely downwards. For this purpose, suitable cover cap plugs 66 are inserted into the upper, obliquely cut ends of the tubes, so that their retaining tongues cling to the inner circumference and, above all, to the centering and retaining ribs 51. This results in a completely smooth, continuous design of the leg, which has no attachment joints for attachment to the frame and which also has no corners and burrs on which items of clothing could get caught.

Bottom glider plugs 67 and 68 are inserted into the tube bundle legs in a suitable profile. Mainly in the front legs 21.1 and 21.2, they hold the three tubular rods 45.3 / 45.4 / 45.5 formed from two pieces together. They are expediently made of suitable plastic in order to avoid damage to the floor.

10 and 11 show the backrest attachment. The plug 82 is shown in the pulled-out position before it is knocked into the leg 21.3.
In order to fasten the backrest 24, longitudinal slots 71 are milled into the upper ends 70 of the rear legs 21.3 and 21.4 in the region of the inward-facing depression 38, the shape of which is shown in FIG. 11 and has a width 72 transverse to the plane 41. The backrest 24 made of flat plywood is brought to the dimension 72 in the area of the retaining walls 74 of the slots 71 by means of longitudinal recesses 73, so that the edges 75 of the backrest 24 are pushed into the slots 71 from above. The height 76 of the edges 25 of the backrest 24 and the depth of the slots 71 are dimensioned such that the upper edges 77 of the lateral recesses 78 lie below the end limit 80 of the leg 21.3 and 21.4 by the amount 79. This creates space for the holding tongues 81 of suitably shaped plugs 82, which form the top surfaces 83 and which are formed in one piece, with elongated slot filling pins 84, which engage in a shape-fitting manner in the upper ends of the slots 71. Above all, the two retaining walls 74 of the tube ends, which are now partially free-standing due to the attachment of the longitudinal slots 71, are held together so that the inner tube regions are not bent up by the bending forces when leaning against the backrest. This is helped by the fact that the longitudinal ribs 51 are arranged correspondingly parallel, so that the supporting forces can be transmitted. The boundary surface 85 of the legs is flush with the oblique boundary surface 86 of the backrest 24, which leads to the high point 87, so that with relatively short rear legs and thus short support lever arms, an elevated support of the back of the user is still possible.

The seat 23 formed from deformed plywood is provided in its deepest area 90 with a plurality of through-bores 91 which allow water to run off during washing, disinfection and the like, and allow ventilation. On the underside 92 of the seat 23 spacers 93.1 and 93.2 are attached, preferably glued, with a matching upper end profile or in corresponding counter-machined recesses. In its lower ends, internally threaded sleeves 94 are inserted, on which the seat is attached (FIG. 12). The spacers designed here as cylinder bodies are aligned with the axes 95 of the fastening recess 27. The walls 96 of the fastening recess 27 have transverse insertion bores 97 at a short distance, each for a U-shaped round wire bracket 98, the legs 98.1 of which have a distance which is slightly greater than the diameter of the bolt 99.1 of a fastening and tensioning screw 99. Washers 101.1 and 101.2 are provided on both sides of the bracket 98 on the bolt 99.1. A spring element 102, excepted in the middle, is supported on the upper washer 101.2. This fits into the mounting recess 27 and is formed here for example as a ring cylinder sleeve made of rubber or rubber-elastic plastic and dimensioned in length so that it protrudes sufficiently over the upper edge 64 of the frame part 22. Another washer 101.3 separates it from the threaded sleeve 94 or the spacer 93 so that damage is avoided. By tightening the screws 99, the heads of which are expediently formed with a hexagon socket or some other inner profile, the seat 23 is held on the one hand. On the other hand, you can determine the preload of the elastically suspended seat and thus the spring characteristics. Since four such fastening and tensioning devices are provided, the initial inclination of the seat 23 can also be determined by appropriately tightening the screws 99, the front or the rear spacers 93 possibly being pulled down to the frame part 22 and the suspension properties being canceled at least for partial areas can.

Stacking pegs 105 are inserted into the fastening recesses 27 from below and, as can be seen in FIGS. 4 and 12, have different lengths 107 and 108 so that they are supported on suitable positions of the seat of the chair underneath when stacked. They have engaging pins 106 which fit into the fastening recesses 27 and shaft parts 109 which are of larger diameter.

As can be seen from FIGS. 2, 3, 5 and 6, the uppermost outer points 103 of the front legs 21.2 and 21.2, which are inclined slightly downward, lie approximately on the line of the inner edges 104 of the rear legs 21.3 and 21.4, which are approximately the lateral outer boundary lines 23.1 of the seat. Several chairs can be stacked by laying the rear legs of the higher chairs next to the seats 23 of the lower chairs and arranging them in front of each other. Accordingly, the front legs are in front of each other when stacking. Such stacks must be tilted so that they do not fall over and cannot be transported and stored.

On such a chair, as can be seen in FIG. 13, an armrest 110 can optionally be attached to each side, which has a vertical round bar 110.1 which runs parallel to the respective rear leg 21.3 or 21.4 and which is attached obliquely according to the oblique boundary surface 86 at the top has an armrest tube 110.2 which is angled vertically downward in its front end region 110.3 and merges under the seat 23 into a horizontal section 110.4 which can be fastened to the frame part 22 with a connecting flange. Here too, the basic principle of forming round rod bundles by inserting them into the recess is retained. The armrest tube 110.2 can be provided with a flat and / or soft support or casing in the support area 112, as is indicated by dash-dotted lines in the left armrest 110 on the right in FIG. 13.

The embodiment of FIGS. 15 to 22 shows a chair similar in design, but which is formed with solid wooden legs. The same parts are provided with the same reference symbols. The frame part 122 is here constructed using a new technique from synthetic resin pressed wood formed with long fibers, but has the same design as the one previously treated, only the ends of the leg connection arms 126 are provided with dovetail-like thickenings 127. The continuous fibers 128 of the arms 126 extend into these. The legs 121 are formed from solid cylindrical round wooden bars 145.1, 145.2, 145.3, 145.4. These are designed with recesses matching the dovetails 127 over a length corresponding to the height 44 of the frame part 122, as can be seen from FIGS. 18 to 21. As can be seen, the correspondingly recessed solid round wooden bars can be attached laterally to the thickenings 127 and connected with glue. The third round bar 145.5 is fastened with countersunk round dowels 129 in the area of the frame part 122 and the thickening 127. In other areas, dowels 130 in the shape of a round or disc can take over the connection. As can be seen, the upper ends of the legs protrude above the arms 126 of the frame part 122 and offer a continuous, straight-line, smooth image, in which the end grain 165 is now visible without cover caps on the obliquely cut off upper end surface 165, unless one is present Paintwork. If, in order to achieve special color effects and, if necessary, to make the front legs appear slimmer, a different coloring of the round bars is desired, the round bars of both the front legs and the rear legs can be painted in different colors before being joined together. The backrest 124 can be fastened in the same way as in the first exemplary embodiment and, if necessary, can be reached through the rods. However, a weak point between the hind legs could result. Therefore, the embodiment shown in FIG. 22 Dovetails 132 screwed on the end face to the vertical boundaries 125 and made of flat metal, for example aluminum, or steel. For their legs 132.1 and 132.2, slots 133 are suitably machined into the upper ends of the rear leg bars. So you can insert the backrest 124 from above. Central bores 134 in the upper free end parts of the leg bars and a suitably shaped insert 135, which can be seen in FIG. 22, close off the upper ends and, above all, hold the two bars securely together, so that the backrest 124 is held.

In a further exemplary embodiment according to FIGS. 23 and 24, a frame part 222 with straight-ended arms 226 is provided. This can consist of metal or composed of individual wooden parts or can also be designed as a molded wooden part. Insert parts of the legs are screwed onto the end faces 227 of the arms 226, which can be provided with threaded sleeves 228 in the case of wood or the like.

T-profile bars 230 are provided for the front legs, the web 231 of which protrudes outwards in the diagonal and is somewhat recessed in the upper end region in order to make room for two fastening bores 234 and the screws 235. The thickness and the length of the web 231 and the leg 232 are dimensioned such that they can be easily inserted into longitudinal grooves 236 which are correspondingly introduced into the round bars, without there being any risk of the wood breaking. The round bars here are essentially cladding of the actual T-shaped support part. However, they protrude upwards beyond the insert and thus completely hide the supporting structure.

Metal flat bars 240 are provided for the rear legs, the thickness and width of which are dimensioned such that the round rods 245.1 and 245.2 made of solid round wood can be plugged on. Through holes 234 for screws 235 are provided at the corresponding points, in a similar manner also in the area of the upper end 241. Here, a suitably dimensioned backrest fastening part 246 is provided, which is T-shaped in cross section and screwed to the flat bar 240 with its flat leg 246.1 and has an inwardly projecting fastening web 246.2, on which the slotted molded wood back 224 is unplugged and secured, for example, with the aid of the pins 247.

In summary, the invention can also be described as follows:
The chair has legs, a seat and a backrest (24). The legs (21.1 to 21.4) are formed from bundles of round rods with at least two round rods. The leg connection arms (26.1 to 26.4) of a frame part are connected in the inward-facing recesses between the round bars. The frame part has a rectangular frame (25), in the corners of which the leg connection arms (26.1 to 26.4) are attached to the diagonals (46). The round bars of the legs are continuous. They can be composed of individual bars and can be designed in different colors. The round bars can be made of light metal tube or solid wood or can be formed with metal inserts.

Claims (33)

1. Chair having the following features:

   - four legs (21, 121);

   - a seat (23);

   - a back rest (24, 124, 224);

   - a body part (22, 122, 222) which connects the legs (21, 121), carries the seat (23) and is constructed as an internal frame part;

   - the seat (23) is held at a distance above the body part (22, 122, 222);

   - the back rest (24, 124, 224) is fastened on the rear legs (21.3, 21.4) which rise upwardly beyond the seat;

   - each of the legs (21) is formed from at least two straight cylindrical round rods (45, 145, 245) which are directly adjacent to one another;

   - the body part (22, 122, 222) has projecting leg-attaching arms (26, 126, 226);

   - the attaching ends (36) of the leg-attaching arms (26, 126, 226) penetrate in each case into the inwardly pointing indentations (38, 39) between the two round rods (45, 145, 245) of each leg;

   - they are connected there to the legs (21, 121) so as to receive the supporting, bending and twisting forces occurring.
2. Chair according to claim 1, characterised in that the legs (21) consist of extruded aluminium tube.
3. Chair according to claim 2, characterised in that two round tubes (45.1, 45.2; 45.3, 45.4) are constructed as a single-piece extruded profile in each case. (Figure 7, Figure 8).
4. Chair according to one of the preceding claims, characterised in that the third tube (45.5) of the front legs (21.1, 21.2) has a pointed external ribs (57) engaging in the indentation (56) between the other two tubes (45.3, 45.4).
5. Chair according to one of the preceding claims, characterised in that the round rods (45) or extruded round tubes have externally longitudinally extending narrow and small protective ribs (60).
6. Chair according to one of the preceding claims, characterised in that the round rods (45) constructed as tubes have longitudinal ribs (51) which extend longitudinally in their interior and serve for centering and fastening.
7. Chair according to at least one of the other claims, characterised in that the leg-attaching arms (26) or the attaching branch (35) thereof and preferably also the fastening of the back rest (24, 124) takes place at a distance (63, 79) below the limits (62, 80) of the round rods (45, 145, 245) of the legs (21).
8. Chair according to at least one of the other claims, characterised in that the round rods (45, 145, 245) of the legs (21) have end faces (65, 165, 85) which are oblique at the top.
9. Chair according to at least one of the other claims, characterised in that appropriate foot-glider stoppers (67, 68) and/or covering cap stoppers (66) and/or stoppers (82) which hold together the tube ends are inserted into the ends of the tubular round rods (45).
10. Chair according to at least one of the other claims, characterised in that the body part (22, 122, 222) connecting the legs (21) and/or carrying the seat (23) has a rectangular frame-shaped base member (25) from the corners of which the leg-attaching arms (26, 126, 226) project diagonally.
11. Chair according to at least one of the other claims, characterised in that the leg-attaching arms (26.1, 26.2; 126, 226) for the front legs (21.1, 21.2, 121.1, 121.2) extend rectilinearly in the chair diagonals (56).
12. Chair according to at least one of the other claims, characterised in that the leg-attaching arms (26.3, 26.4, 126, 226) for the rear legs (21.3, 21.4; 121.3, 121.4) extend diagonally, preferably in the diagonals (46), to the connecting plane (40) connecting the rear legs and, in each case, have an attaching branch (35) angled into the connecting plane (40) of the rear legs.
13. Chair according to at least one of the other claims, characterised in that the ends (36) of the leg-attaching arms (26) and the attaching branches (35) provided thereon are tapered and bevelled.
14. Chair according to at least one of the other claims, characterised in that vertically extending recesses (27) of preferably cylindrical shape are provided in the corners of the rectangular frame (25) of the body part (22) to receive the fastening of the seat (23) and optionally stack supporting pegs (105).
15. Chair according to at least one of the other claims, characterised in that the body part (22) consists of four extruded light metal profile parts (22.1, 22.2, 22.3, 22.4) which are cut off according to the height (44) and are connected to one another.
16. Chair according to claim 15, characterised in that the body part elements (22.1, 22.2, 22.3, 22.4) constructed as light metal profile parts have, in thickened ends (29), connecting slots (30) for appropriately inserted tabs and/or bevels (31) for a weld seam (32).
17. Chair according to at least one of the other claims, characterised in that the upper ends (70) of the rear legs (21.3, 21.4) are equipped with vertically extending slots (71; 133) for insertion of the edges (75, 132) of the back rests (24, 124).
18. Chair according to claim 17, characterised in that the slots (71) introduced into the light metal extruded profiles of the rear legs (21.3, 21.4) are covered, after insertion of the shallowly curved back rest (24) which is preferably tapered in the insertion region (73), by a respective stopper (82) which is inserted into the ends of the tubular round rods (45.1, 45.2) and secures them against lateral outward bending.
19. Chair according to at least one of the other claims, characterised in that the upper ends (70) of the rear legs (21.3, 21.4; 121.3, 121.4) are cut off at oblique limiting planes aligned with the obliquely extending upper limiting faces (86) of the back rest (24, 124) and are optionally sealed with stoppers (82) ending in these planes.
20. Chair according to at least one of the claims, characterised in that the legs (121.1, 121.2, 121.3, 121.4) consist of cylindrical round wood rods (145.1, 145.2, 145.3, 145.4) which are connected to one another and consist of solid wood.
21. Chair according to claim 20, characterised in that the body part (122) connecting the legs (121) and carrying the seat (23) has, at the ends of its leg-attaching arms (126), dovetail-like thickenings (127) which are placed in appropriately hollowed indentations in two adjacent round rods (145.1, 145.2; 145.3, 145.4) which are placed and preferably glued thereon.
22. Chair according to at least one of the other claims, characterised in that the body part (122, 222) connecting the legs (21, 121) and carrying the seat (23) consists of compression-moulded plastics material/fibre/wood, on which the outwardly projecting leg-attaching arms (126, 226) are shaped with continuously extending fibres (128).
23. Chair according to at least one of the other claims, characterised in that the back rest (124) has, on each side, a metal profile (132) which is shaped in the manner of a dovetail, is attached to the vertical limit (125) of the back rest (124) and engages in vertically machined slots (133) in the adjacent round wood rods (145.1, 145.2) of the rear legs (121.3, 121.4).
24. Chair according to at least one of claims 20 to 23, characterised in that the third round wood rod (145.5) of the bundle of the front legs (121.1, 121.2) is glued by means of concealed dowels (129, 130) on the leg-attaching arms (126) and their thickenings (127) of the body part (122) and optionally the round wood rods (145.3, 145.4) of the legs (121).
25. Chair according to at least one of claims 1, 7, 8, 10, 12, 20, characterised in that a body part (222) consisting of metal or compression-moulded pulp wood is provided, on the leg-attaching arms (226) and attaching branches (35) of which there is attached, preferably screwed, in the rear region, a respective vertically extending flat rod (240) and on the leg-attaching arms (226) for the front legs there is attached, preferably screwed, a respective T-profile rod (230) pointing outwardly at 45° with the web (231), in which the length and thickness of the web (231) and of the branches (231.1, 231.2) is substantially smaller than the diameter of the round wood rods (245) and in that the round wood rods (245) are provided with appropriate longitudinal grooves (236) by means of which they are placed onto the branches of the flat rods (240) and of the T-profile rods (230).
26. Chair according to claim 25, characterised in that the round wood rods (245) protrude upwardly beyond the inlaid flat rods (240) and/or T-profile rods (230).
27. Chair according to at least one of claims 20 to 26, characterised in that the round wood rods (145, 245) are machined off at their upper ends in markedly inclined end faces (125).
28. Chair according to at least one of the other claims, characterised in that, beneath the seat (23) there are fastened spacer members (93.1, 93.2) in the lower end of which there are provided threaded bores (94) by means of which the seat (23) is fastened on the body part (22, 122, 222) with interposition of spring elements (102).
29. Chair according to claim 28, characterised in that the spring elements (102) are penetrated by screws (99) by means of which the initial spring tension and/or the inclination of the seat (23) can be adjusted.
30. Chair according to claim 29, characterised in that the heads of the screws (99) are fastened axially unmovably in fastening recesses (27) of the body part (22).
31. Chair according to claim 30, characterised in that the lateral walls (96) of the fastening recesses (27) have, on the body part (22) in the region of the heads of the screws (99) and of the spring elements (102), insertion bores (97) which penetrate them and through which round wire stirrups (98) surrounding the bolts (99.1) of the screws (99) but securing them against axial displacement are inserted.
32. Chair according to at least one of the other claims, characterised in that the seat (23) consists of an unpadded, rigid, wipeable material such as plastic wood or metal, and is provided, in its lowest region, with through-bores (91) for liquids.
33. Chair according to at least one of the other claims, characterised in that it is equipped with arm rests (110) such that they have a vertical round rod (110.1) which is laid into the indentation (55), pointing away from the attachment to the body part (22), of each rear leg (21.3, 21.4) and is fastened thereon, and wherein the substantially horizontally extending arm rest tube (110.2) is attached to the vertical round rod, preferably with an obliquely extending kink and passes, at its front end, into a vertical front end region to which there is attached a horizontal portion (110.4) which is bent beneath the seat (23) and is preferably fastened on the body part (22).

Images