EP1908374B1 - Synchronous office chair - Google Patents

Abstract

The office chair has a seat support (2) implementing a tilting movement about a tilting axis (4) with a clamp (5). A rear part (3) implements another tilting movement about a virtual axis (13) with a rear bracket (6), where the latter tilting movement is approximately two or three times larger than the former tilting movement in accordance to amount and at the same time implements a translatory movement. A momentary pivotal point of the latter tilting movement lies in a constant distance over a rear middle part of the seat support.

Description

The invention relates to a synchronous office chair according to claim 1.

As a synchronous office chair is commonly referred to a chair in which a seat part and a backrest part can perform coupled movements. For example, such an office chair can be designed so that the inclination of the backrest part is coupled with a smaller inclination of the seat surface part.

More particularly, the present invention relates to a synchronous office chair having substantially three main parts cooperating to provide synchronous movement of the synchronous office chair. These three main parts are arranged on a support column and comprise a support fixedly connected to the support column, a seat support hinged to the support on a tilting axis and a back part which is coupled to the support and the seat support. The tilting axis is located under the front area of the seat, ie approximately in the knee area of the seated person.

Although there are already many synchronous office chairs already known that have synchronous mechanisms, such as the US 5,354,120 or the US 6,431,649 , However, they usually consist of joint mechanisms and they often have the disadvantage that the synchronous movement of the seat surface part and the backrest part is ergonomically unfavorable insofar as the "pull out" effect occurs. By this is meant the well-known effect that a seated person, when leaning backwards, somehow pulls the shirt out of his pants. This is a consequence of the fact that the coupled relative or synchronous movements of the seat part and the Backrest part (at least in this respect) are unfavorably matched.

The object of the invention is to provide an improved synchronous office chair, in which the undesirable "pull-out" effect is largely avoided.

This object is achieved by the feature combination of claim 1.

Furthermore, also a well integrated in the improved synchronous mechanism device for limiting the synchronous movement in the form of an inclination stop and a device for decelerating the synchronous movement in the form of a bias voltage should be specified.

• einem mit einer Tragsäule fest verbundenen Träger,
• einem am Träger an einer Kippachse angelenkten Sitzträger und einem mit dem Sitzträger fest verbundenen Horn,
• einem Rückenteil und einem mit dem Rückenteil fest verbundenen Rückenbügel, wobei der Rückenbügel
  • -- eine erste Kurvenbahn,
  • -- eine zweite Kurvenbahn, und
  • -- eine dritte Kurvenbahn aufweist, und
  • -- wobei der Rückenbügel des Rückenteils in einen Zwischenraum zwischen dem Träger und dem Sitzträger eingreift und wobei das Horn des Sitzträgers in den Rückenbügel eingreift,

und wobei der Sitzträger mit dem Horn und das Rückenteil mit dem Rückenbügel zur Ausführung einer Synchronbewegung ausgebildet sind.An inventive synchronous office chair therefore consists essentially of the following parts:

• a support fixedly connected to a support column,
• a seat support hinged to the support on a tilt axis and a horn fixedly connected to the seat support,
• a back part and a backrest fixedly connected to the back part, wherein the back strap
  • a first curved track,
  • - a second curved path, and
  • - Has a third curved path, and
  • - Wherein the back strap of the back part engages in a space between the carrier and the seat carrier and wherein the horn of the seat carrier engages in the back strap,

and wherein the seat carrier with the horn and the back part are formed with the back strap for performing a synchronous movement.

• am Horn des Sitzträgers ein erstes Rollenlager angebracht, das in die erste Kurvenbahn des Rückenbügels eingreift und bei der Synchronbewegung des Bürostuhls in der ersten Kurvenbahn geführt wird,
• am Sitzträger ein zweites Rollenlager angebracht, das in die zweite Kurvenbahn des Rückenbügels eingreift und bei der Synchronbewegung des Bürostuhls in der zweiten Kurvenbahn geführt wird,
• am Träger ein drittes Rollenlager angebracht, das in die dritte Kurvenbahn des Rückenbügels eingreift und bei der Synchronbewegung des Bürostuhls in der dritten Kurvenbahn geführt wird.

Furthermore, in the synchronous office chair according to the invention:

• attached to the horn of the seat carrier, a first roller bearing, which engages in the first curved path of the back bracket and is guided in the synchronous movement of the office chair in the first curved path,
• attached to the seat support a second roller bearing which engages in the second curved path of the back bracket and is guided in the synchronous movement of the office chair in the second curved path,
• attached to the carrier a third roller bearing, which engages in the third curved path of the back bracket and is guided in the synchronous movement of the office chair in the third curved path.

• der Sitzträger mit dem Horn eine erste Kippbewegung um die Kippachse ausführt,
• das Rückenteil mit dem Rückenbügel eine zweite Kippbewegung um eine virtuelle Achse ausführt, die betragsmässig etwa zwei- bis dreimal so gross ist wie die erste Kippbewegung und gleichzeitig auch eine translatorische Bewegung ausführt,
• und zudem der momentane Drehpunkt der zweiten Kippbewegung um die virtuelle Achse im wesentlichen stets etwa im gleichen Abstand über dem hinteren mittleren Teil des Sitzträgers liegt.

The synchronous movement in the synchronous office chair is formed by means of the aforementioned parts such that

• the seat support with the horn performs a first tilting movement about the tilting axis,
• the back part carries out a second tilting movement about a virtual axis with the back strap, which amount is approximately two to three times as large as the first tilting movement and at the same time also performs a translatory movement,
• and moreover, the instantaneous pivot point of the second tilting movement about the virtual axis is substantially always approximately the same distance above the rear central part of the seat support.

The advantages of this solution are, in particular, that it can be adapted to complex lever mechanisms and in particular the main goal, namely the avoidance of the "pull-out" effect is achieved. With only two main moving parts, namely the seat support and the back part, this goal can already be achieved.

The synchronous movement, i. the positively driven relative movement of seat support and back part is achieved by the leadership of the roller bearings in the curved paths. The disclosed arrangement of the roller bearings and the cam tracks causes the instantaneous pivot point of the tilting movement of the back part about the virtual axis to be essentially always approximately the same distance above the rear central part of the seat carrier. Thus, in a human seated and reclining on the synchronous office chair, the body pivot point and the instantaneous pivot point of the back rest tilting about the virtual axis are largely in agreement, resulting in the desired goal.

As already mentioned, the improved synchronous mechanism can also be well combined with a device for slowing down the synchronous movement - namely in the form of a bias voltage. Here, the goal is to achieve an adjustable cushioning of the seat support and the back part, which is optimally suitable and adjustable for very light as well as for very heavy people, and also has a very high reliability and durability. Through the use of leaf springs with sliding support and the use of a bevel gear for shifting or positioning of the supports not only achieves a simple mechanical structure but also the desired scope of application.

In fact, it has been found that in particular leaf springs made of a glass fiber plastic composite material with unidirectionally directed glass fibers provide the necessary strength values and in particular the desired service life. Other materials, such as steel springs and the like, on the other hand, tend to break fatigue much more quickly and, moreover, can not usually be used for the entire range of applications from very light to very heavy Persons are suitably dimensioned.

As already mentioned, the improved synchronous mechanism can also be combined well with a device for limiting the synchronous movement - here in the form of a tilt stop. The user of the synchronous office chair according to the invention should be able to adjust and change the maximum inclination of the back part or of the seat support in a simple manner. Through the use of a toothed segment on the support and a gear with a stop disc and a grid lever in a tilting mechanism holder on the seat support and an actuator for actuating the grid lever can be achieved here the desired simple and reliable mechanical structure. The mentioned elements for realizing the inclination stop ultimately cause the gear that runs on the toothed segment - depending on the setting of the inclination stop - can only depart a certain way on the whole available path on the sector gear. If the locking lever is not engaged in the stop disc, the entire available path on the toothed segment can be utilized. The user can therefore, for example by means of a push button on a cable, solve the grid lever of the stop disc and tilt the synchronous office chair in any tilt position (within the entire possible range of synchronous movement) to the rear to pick a new stop position. Thus, here too results in a very simple and convenient operation.

In the following, an embodiment of an inventive office chair will be explained in more detail with reference to drawings.

Fig. 1

eine schematische Seitenansicht eines SynchronBürostuhls mit einem Träger, einem Sitzträger und einem Rückenteil bei einer Sitzträgerneigung von 0°,

Fig. 2

eine schematische Seitenansicht des Synchron-Bürostuhls gemäss Fig. 1 bei einer Sitzträgerneigung von 11°,

Fig. 3

eine räumliche Ansicht des Trägers gemäss Fig. 1 von oben,

Fig. 4

eine räumliche Ansicht des Sitzträgers gemäss Fig. 1 von oben,

Fig. 5

eine räumliche Ansicht des Rückenteils gemäss Fig. 1 von vorne,

Fig. 6

eine schematische Seitenansicht des Trägers und des Sitzträgers mit der prinzipiellen Anordnung der Elemente der Vorspannung,

Fig. 7

eine Freistellung der Elemente der Vorspannung,

Fig. 8

eine räumliche Ansicht des Trägers mit den Elementen der Vorspannung,

Fig. 9

eine schematische Seitenansicht des Trägers und des Sitzträgers mit der prinzipiellen Anordnung der Elemente des Neigungsanschlages,

Fig. 10a

eine schematische Darstellung der Elemente des Neigungsanschlages in der 0°-Position, und

Fig. 10b

eine schematische Darstellung der Elemente des Neigungsanschlages in der 6°-Position.

In the drawings show:

Fig. 1

a schematic side view of a synchronous office chair with a carrier, a seat support and a back at a Sitzträgernigung of 0 °,

Fig. 2

a schematic side view of the synchronous office chair according Fig. 1 at a seat post inclination of 11 °,

Fig. 3

a spatial view of the carrier according to Fig. 1 from above,

Fig. 4

a spatial view of the seat support according Fig. 1 from above,

Fig. 5

a spatial view of the back according to Fig. 1 from the front,

Fig. 6

a schematic side view of the carrier and the seat carrier with the basic arrangement of the elements of the bias voltage,

Fig. 7

an exemption of the elements of the prestress,

Fig. 8

a spatial view of the carrier with the elements of the bias,

Fig. 9

a schematic side view of the carrier and the seat support with the basic arrangement of the elements of the inclination stop,

Fig. 10a

a schematic representation of the elements of the tilt stop in the 0 ° position, and

Fig. 10b

a schematic representation of the elements of the tilt stop in the 6 ° position.

The FIG. 1 shows a schematic side view of a synchronous office chair with a support 1, a seat support 2 and a back part 3 at a Sitzträgernigung of 0 °. Two of these three "main parts", namely the seat support 2 and the back part 3 are movable in such a way that a synchronous movement is created. Because the FIG. 1 (as well as the FIG. 2 ) serve mainly to clarify the basic arrangement of the main parts, the carrier 1, the seat support 2 and the back part 3 for the purpose of representing their shape in the Figures 3-5 also shown in spatial representations.

The carrier 1 is fixedly connected to a support column (not shown). The support column can be mounted in a manner customary for office chairs on an office chair foot part. On the support 1, the seat support 2 is articulated on a tilting axis 4. The seat support 2 has a rearwardly and upwardly toward the back part 3 extending horn 5. Seat support 2 and horn 5 are firmly connected. The back part 3 has a back bracket 6 extending downwards and toward the direction of the seat support 2. Back part 3 and back bar 6 are also firmly connected. The back bar 6 of the back part 3 engages in a space between the carrier 1 and the seat support 2, and the horn 5 of the seat support 2 engages in the back strap 6 a.
The back yoke 6 has a first curved track 7, a second curved track 8, and a third curved track 9.

The curved paths 7, 8, 9 are all approximately circular-arc-like and concave from the point of view of a viewer standing in front of and above the synchronous office chair. In addition, the second and third curved paths 8, 9 are brought together so closely from a lateral view (as shown here) that there is an overlap.

At the horn 5 of the seat support 2, a first roller bearing 10 is mounted, which engages in the first curved path 7 of the back yoke 6 and is guided in the synchronous movement of the office chair in the first curved path 7.

On the seat support 2, a second roller bearing 11 is mounted, which engages in the second curved path 8 of the back yoke 6 and is guided in the synchronous movement of the office chair in the second curved path 8.

On the carrier 1, a third roller bearing 12 is mounted, which engages in the third curved path 9 of the back bracket 6 and is guided in the synchronous movement of the office chair in the third curved path 9.

Now, if a user sits down on the synchronous office chair and leaning back, then run the seat support 2 and the back part 3 of the aforementioned synchronous movement. The seat support 2 with the horn 5 makes a first tilting movement about the tilting axis 4. The back part 3 with the back yoke 6 makes a second tilting movement about a virtual axis 13 which is about two to three times as large as the first tilting movement. At the same time makes the back part 3 with the back bar 6 is still a translational movement down and forward. During the synchronous movement of the instantaneous pivot point of the second tilting movement about the virtual axis 13 is substantially always approximately the same distance above the rear central part of the seat support. This is from the FIGS. 1 and 2 , which are drawn on the same scale, clearly visible. Thus, the movements of the seat support 2 and the back part 3 are mutually positively guided or coupled together, which is why one speaks of a synchronous movement. The position of the virtual axis is chosen so that it essentially always corresponds to the pelvic pivot of a person sitting on the inventive synchronous office chair.

The property of the synchronous office chair according to the invention that during the synchronous movement the instantaneous pivot point of the second tilting movement about the virtual axis 13 remains essentially always approximately the same distance above the rear central part of the seat carrier is intended and is represented by the structure of the synchronous Mechanics, in particular the arrangement of the cam tracks 7,8,9 and the roller bearings 10,11,12 achieved. It causes the aforementioned "pull-out" effect does not occur or at least is very much minimized.

The FIG. 2 shows a schematic side view of the synchronous office chair according Fig. 1 at a seat post inclination of 11 °. Here it is clearly visible that the back part 3 with the back bar 6 has made a sliding movement downwards and forwards and simultaneously also a rotational movement about the virtual axis 13. For clarification, the instantaneous position of the virtual axis 13 is also shown here. It should be noted that the distance of the virtual axis 13 to the upper edge of the seat support 2 has barely changed.

Also note that here (also in terms of FIG. 1 ) the stationary position of the third roller bearing 12 on the carrier 1 is clearly visible. Equally clearly visible (again in relation to FIG. 1 ), the stationary position of the second roller bearing 11 on the seat support. 2

The FIG. 3 shows for clarity a spatial view of the carrier according to Fig. 1 , in the view from above and behind. Particularly clearly visible here is the third roller bearing 12th

The FIG. 4 shows for clarity a spatial view of the seat support according to Fig. 1 , in the view from above and in front.

The FIG. 5 shows for clarity a spatial view of the back according to Fig. 1 , in the view from the front and above. Particularly clearly visible here are first, second and third curved path 7,8,9.

The FIG. 6 shows a schematic side view of the carrier 1 and the seat support 2 with the basic arrangement of the elements of the bias. The most important elements of the prestressing comprise at least one leaf spring 20, a support device 21, a support 22, a support surface 23 and a positioning device 24 for the support 22 on the support surface 23.

The at least one leaf spring 20 is used to generate a biasing force for the bias and is fixed to a first leaf spring end 25 in the region of the tilting axis 4 on the carrier 1. The second (opposite) leaf spring end 26 is arranged vertically movable and resilient in the area below the rear middle part of the seat support 2. The seat support 2 is supported by means of the support means 21 attached thereto at the rear central part of the seat support 2 rolling or sliding on the / the leaf spring (s) or can be supported thereon. The at least one leaf spring 20 in turn is supported on the support surface 23 rolling or slidingly displaceable support 22. Thus leaves itself by displacement or positioning of the support 22 on the support surface 23, the biasing force for the bias - so the first tilting movement of the seat support 2 counteracting force - continuously adjusted.

The positioning device 24 for the support 22 on the support surface 23 may be configured in various ways, but advantageously it is adjustable via a bevel gear 27 whose drive axis is arranged coaxially to the tilting axis 4.

The at least one leaf spring 20 preferably consists of a glass fiber-plastic composite material with unidirectionally directed glass fibers. The strength values and the reliability of these (today common) materials are so good that can be realized with the disclosed leaf spring design preloads in a range of forces that can cover the entire range of application of very light to very heavy people.

The FIG. 7 shows for the sake of further clarification an exemption of the elements of the bias. Shown here is a bias with two parallel leaf springs 20, wherein the support means for the leaf springs 20 are formed here as a substantially cylindrical, slidable supports 22, and wherein the two supports 22 together by means of a shaft 28 and a threaded spindle 29 via the bevel gear 27th on the support surface 23 (see Fig. 6 ) can be slidably positioned. Of course, rolling supports could also be provided.

The FIG. 8 shows a spatial view of the carrier 1 with the elements of the bias voltage. In addition visible here are next to the bevel gear 27 plastic inserts 30 in which the leaf springs 20 at the first leaf spring ends 25th be held and fixed. By means of a crank 31, the threaded spindle 29 via the bevel gear 27 is rotatable. Since the threaded spindle 29 is guided in a threaded hole of the shaft 28, by rotation on the crank 31, the position of the supports 22 on the bearing surface - and thus the biasing force for the bias - can be adjusted.

The FIG. 9 shows a schematic side view of the carrier 1 and the seat support 2 with the basic arrangement of the elements of the inclination stop. The most important elements of the inclination stop include a toothed segment 40 attached to the carrier 1 and a tilting mechanism holder 41 attached to the seat carrier 2. The tilting mechanism holder 41 in turn essentially contains a toothed wheel 42, a stop disc 43 and a ratchet lever 44 Tilting axis 4 moves the gear 42 on the sector gear 40 a certain way - here, of course, a circular arc segment - from. In the present exemplary embodiment, this path, or the circular arc segment, is approximately 11 ° (angle degree) at a maximum when the inclination stop is fully released (deactivated). Because the gear 42 (in the present geometric conditions and because of the relatively narrow arc segment) when rolling on the sector gear 40 undergoes no complete revolution, it does not need to be provided with a toothing over the entire circumference. When activated inclination stop the rolling movement of the gear 42 is blocked on the sector gear 40 at a certain Abrollposition. The activation / deactivation of the inclination stop is carried out via an actuation of the grid lever 44, which can be done for example by means of a push button via a cable. Other actuation mechanisms, for example via linkage, are well known to those skilled in the art and of course, of course, may also be used.

The structure and operation of the tilt stop is based on the Figures 10a and 10b explained in more detail. It should be noted here only that the Figures 9 and 10 Represent views from opposite sides. However, this does not change the functional principle.

The FIG. 10a shows a schematic representation of the elements of the inclination stop in the 0 ° position (the maximum inclination of the seat support 2 about the tilting axis 4 is here 0 °). For the purpose of concentrating on the essential functional elements, the remaining parts of the synchronous office chair are omitted in this drawing.

• Das Zahnrad 42, weist einen Zahnradanschlag 45 auf. Wie bereits erwähnt, braucht das Zahnrad nicht über den ganzen Umfang verzahnt zu sein. Der Zahnradanschlag 45 wird hier durch eine Flanke eines ersten Zahnradzahnes gebildet, es kann aber auch ein separater, mit dem Zahnrad fest verbundener Zahnradanschlag vorhanden sein.
• die Anschlagscheibe 43 weist einen Scheibenanschlag 46 auf. Der Scheibenanschlag 46 ist zur Anlage bzw. Anschlag am Zahnradanschlag 45 ausgestaltet. Die Anschlagscheibe 43 weist zudem entlang ihres Umfangs eine Reihe von Rasterzähnen 47 auf. Auch hier brauchen die Rasterzähne nicht auf dem gesamten Umfang der Anschlagscheibe vorhanden zu sein und auch hier könnte ein separater Scheibenanschlag vorgesehen sein.
• das Zahnrad 42 und die Anschlagscheibe 43 sind koaxial und zumindest teilweise gegenseitig verdrehbar auf einer Achse 48 in der Neigungsmechanikhalterung 41, die ihrerseits am Sitzträger 2 angebracht ist, gelagert. Die nur zumindest teilweise mögliche gegenseitige Verdrehbarkeit ergibt sich, wenn der Zahnradanschlag 45 und der Scheibenanschlag 46 gegenseitig in Anschlag stehen (was hier der Fall ist).
• der Rasterhebel 44 ist an einer Schwenkachse 49 in der Neigungsmechanikhalterung gelagert und greift mit einem Arretiernocken 50 in die Rasterzähne 47 des Scheibenanschlages 46 ein. Der Rasterhebel 44 ist mittels eines (nicht dargestellten) Seilzuges über eine Oese 51 betätigbar.

The parts in the tilting mechanism mount 41, that is to say the gearwheel 42, the stopper disk 43 and the ratchet lever, are constructed as follows in this exemplary embodiment:

• The gear 42 has a gear stop 45. As already mentioned, the gear need not be toothed over the entire circumference. The gear stop 45 is formed here by an edge of a first gear tooth, but it may also be a separate, fixed to the gear gear stopper be present.
• the stop disc 43 has a disc stop 46. The disc stop 46 is designed for abutment or stop on the gear stop 45. The stop disc 43 also has along its circumference a series of raster teeth 47. Again, the grid teeth do not need to be present on the entire circumference of the stop plate and also here a separate disc stop could be provided.
• the gear 42 and the stopper plate 43 are coaxial and at least partially mutually rotatable on an axis 48 in the tilting mechanism mount 41, which in turn is mounted on the seat support 2, stored. The only at least partially possible mutual rotatability results when the gear stopper 45 and the disc stop 46 are mutually abutting (which is the case here).
• the grid lever 44 is mounted on a pivot axis 49 in the inclination mechanism holder and engages with a locking cam 50 in the grid teeth 47 of the disc stop 46 a. The grid lever 44 can be actuated by means of a cable (not shown) via an eyelet 51.

In the FIG. 10a the inclination of the seat support 2 (not shown here) has a tilt angle of 0 ° (inclination about the tilting axis 4). The tilt stop is activated because the locking cam 50 of the grid lever 44 engages in the ratchet teeth 47 of the stop plate 43 and therefore prevents rotation of the stop plate 43. If a person sat down on the synchronous office chair, the gear 42 would go down in a counter-clockwise rotation on the toothed segment 40 when the tilt stop was not activated. This movement is blocked here but because of the abutting gear stop 45 and disc stop 46. The synchronous movement of the office chair is thus completely prevented here.

In contrast to the state described above, when the inclination stop is deactivated, the locking cam 50 of the grid lever 44 does not engage in the ratchet teeth 47 of the stop disc 43. Thus, the user of the synchronous office chair can recline with the tilt stop disabled, for example, up to a tilt of the seat support 2 by a tilt angle of 6 ° (inclination about the tilt axis 4), whereby the gear 42 and the stop plate 43 in the FIG. 10b reach shown position. If the user of the synchronous office chair decides that this position should be the maximum tilt position desired by him, he can in turn activate the inclination stop in this position, ie he can let snap the grid lever 44 with the locking cam 50 in this position again in the grid teeth 47 of the stop plate. This is so in the FIG. 10b shown.

The Fig. 10b Thus, finally shows a schematic representation of the elements of the inclination stop in the 6 ° position (the maximum inclination of the seat support 2 about the tilting axis 4 is here 6 °). The tilt stop is activated because the locking cam 50 of the grid lever 44 engages in the ratchet teeth 47 of the stop plate 43 and therefore prevents rotation of the stop plate 43. By contrast, here is the tilting movement of the seat support 2 in the inclination range between 0 ° and 6 ° possible because the gear 42 and the stop plate 43 are at least partially mutually rotatable on the axis 48 are arranged. Would in the example of the Fig. 10b Thus, the angle of inclination is reduced, so the gear 42 would go in clockwise rotation on the toothed segment 40, because this mutual rotation between the gear 42 and stop plate 43 is not hindered by the stops 45,46. Thus, the disclosed inclination stop acts as a means for limiting the synchronous movement, ie the synchronous movement can be limited in one of the selectable rotational position of the stop disc 43 corresponding inclination position of the seat support 2 and the back part 3.

Of course, the geometry and the design of the inventive tilt stop need not necessarily correspond exactly to the embodiment shown. For example, the gear 42 with gear stopper 45 and the stopper plate 43 with the disc stopper 46 must not be made in one piece and neither the gear 42 nor the stopper plate 43 need only be provided on a part of its circumference with a toothing.

Overall, both the device for the tilt stop as well as the device for the bias voltage are particularly suitable to be used in an office chair with a synchronous movement designed according to the invention. The inclination stop allows an optional and particularly easy-to-use limitation of the synchronous movement with simple means, while the bias is mainly due to the very large adjustment range, but certainly also because of the basic simplicity, well suited.

As mentioned earlier, in the illustrated embodiment, the seat support 2 and the horn 5 are firmly connected together, as well as the back part 3 and the back bar 6. Of course, it is structurally readily possible to make the corresponding parts either assemblable or in one piece.

List of reference numerals:

1

carrier

2

seat support

3

back

4

tilt axis

5

horn

6

back support

7

1st curved track

8th

2nd curved path

9

3rd curved path

10

1. Roller bearings

11

2. Roller bearings

12

3. Roller bearings

13

virtual axis

14-19

not used

20

leaf spring

21

support means

22

In stock

23

bearing surface

24

Positioning device (for the support)

25

1. leaf spring end

26

2nd leaf spring end

27

bevel gear

28

wave

29

screw

30

Plastic insert

31

crank

32-39

not used

40

gear segment

41

Inclination mechanism holder

42

gear

43

stop disc

44

grid lever

45

gear stop

46

glass-stop

47

grid teeth

48

axis

49

swivel axis

50

locking boss

51

Eyelet

Claims (7)

1. Synchronised office chair, having

   - a support (1) rigidly connected to a support column,

   - a seat support (2) hinge-jointed to the support (1) on a tilting axle (4), and a horn (5) that is rigidly connected to the seat support (2),

   - a back part (3) and a back frame (6), wherein the back frame (6) has

   - a first curved track (7),

   - a second curved track (8), and

   - a third curved track (9), and

   - wherein the back frame (6) of the back part (3) engages in a cavity between the support (1) and the seat support (2) and wherein the horn (5) of the seat support (3) engages in the back frame (6),

   and wherein the seat support (2) with the horn (5) and the back part (3) with the back frame (6) are constructed for executing a synchronised motion, and where additionally in said synchronised office chair

   - a first roller bearing (10) is mounted on the horn (5), which engages in the first curved track (7) of the back frame (6) and during the synchronised motion of the office chair is guided in the first curved track (7),

   - a second roller bearing (11) is mounted on the seat support (2), which engages in the second curved track (8) of the back frame (6) and during the synchronised motion of the office chair is guided in the second curved track (8),

   - a third roller bearing (12) is mounted on the support (1), which engages in the third curved track (9) of the back frame (6) and during the synchronised motion of the office chair is guided in the third curved track (9),

   and the synchronised motion of the synchronised office chair is configured in such a way that

   - said seat support (2) executes a first tilting movement with the horn (5) about the tilting axle (4),

   - said back part (3) executes a second tilting movement with the back frame (6) about a virtual axis (13), which in extent is about twice or three times as large as the first tilting movement, and simultaneously also executes a translational movement,

   - and in addition the instantaneous fulcrum of the second tilting movement about the virtual axis (13) is always substantially at about the same distance above the rear central part of the seat support (2).
2. Synchronised office chair according to Claim 1, characterized in that a device for limiting the synchronised motion in the form of a reclining stop is present, and/or a device for slowing down the synchronised motion in the form of a pretension is present.
3. Synchronised office chair according to Claim 2, characterized in that at least one leaf spring (20) is mounted on the support (1) for applying a pre-tensioning force for the pretension, wherein

   - the at least one leaf spring (20) is fixed at a first leaf spring end (25) in the region of the tilting axle (4) on the support (1), and at a second leaf spring end (26) is arranged in a moveable and elastic manner in the region below the rear central part of the seat support (2), and

   - said seat support (2) is or can be supported by means of a support device (21) on the rear central part of the seat support (2), rolling or sliding on the leaf spring (20), and

   wherein a support (22), displaceable in a rolling or sliding manner on a support surface (23), is present, on which the at least one leaf spring (20) is supported and wherein the pre-tensioning force can be adjusted by displacement of the support (22) on the support surface (23).
4. Synchronised office chair according to Claim 3, characterized in that the positioning of the support (22) is adjustable by means of a conical gear drive (27).
5. Synchronised office chair according to Claim 3 or 4, characterized in that the at least one leaf spring (20) consists of a fibreglass-plastic composite material with unidirectionally aligned glass fibres.
6. Synchronised office chair according to Claim 2, characterized in that a toothed segment (40) is mounted on the base (1) and a cog (42) with a stop plate (43) and a locking lever (44) are mounted on the seat support (2) in a reclining mechanism support (41), wherein

   - said cog (42) engages in the toothed segment (40) and can be moved up and down during the synchronised motion,

   - the cog (42) comprises a cog stop (45),

   - the stop plate (43) comprises a plate stop (46),

   - the cog (42) and the stop plate (43) are mounted coaxially on an axle (48) and are at least partially mutually rotatable, and

   - the stop plate (43) can be locked by means of the locking lever (44) in a selectable rotary position with respect to the reclining mechanism support (41),

   wherein the synchronised motion can be limited in a reclining position of the seat support (2), or of the back part (3), corresponding to the selectable rotary position of the stop plate (43) in which the cog stop (45) and the plate stop (46) are mutually limited.
7. Synchronised office chair according to Claim 6, characterized in that said locking lever (44) can be detached, or disengaged, from the stop plate (43) by means of an activation device and in the reclining position of the seat support (2), or of the back part (3), corresponding to the selectable rotary position of the stop plate can be reengaged into the stop plate (43).

Images