DE19931099C2 - Chair with independent adjustment of the preload force of the backrest - Google Patents

Description

The present invention relates to a chair with a Seat plate, with a seat support carrying the seat plate ger, that with a central chair column or more Is connected to the legs of the chair, and to a back support, the one under the seat plate to the rear and behind the seat plate runs up and carries a backrest where at the seat plate near its front edge by one hori zontally transverse first pivot axis pivotable on the seat support and offset from it by one parallel second pivot axis pivotable on the back is supported articulated, the backrest support by one between the first and second pivot axes parallel to the running third pivot axis pivotable on the Seat support is articulated and being under the seat plate a compression spring arrangement supported on this hen is that on the seat plate one up and on the backrest a forward-acting preload exercises power.

A chair of the type mentioned is from DE 43 13 301 C2 known. It is specifically provided that at the sub side of the seat plate in the front and rear area Columns fixed downwards in pairs are, with the lower ends of the front supports with the lower ends of downward, pivotable  handlebars attached to the seat support and the lower ends the rear supports can be swiveled with the backrest support are bound, and that the compression spring assembly between the seat plate and the seat support is arranged. With this construction of the chair becomes a so-called syn chron mechanics achieved, when loading the rear part of the seat plate lowered this back and at the same time the backrest ver is pivoted, the pivoting angle of the backrest is usually larger than the swivel angle of the seat plate. The ratio of the swivel angle to each other is determined by the interacting lever lengths.

The disadvantage of this known chair is angese hen that the preload of the backrest only from the strength of the compression spring assembly and the Kon structure of the chair depends on the leverage so that in no way an adjustment of the preload thanks to the backrest to different body weights different users of the chair is possible. A Be influence of the preload force of the backrest would be by using an adjustable or preload ble compression spring arrangement possible, but must be for this the user of the chair makes the adjustment manually ren, which is an undesirably high effort, be especially if a chair is different and different heavy users. Besides, it is not ensures that the user will actually fit the de takes what causes wrong and under Um even harmful settings of the board load capacity of the backrest can result.

Furthermore, EP 0 277 474 A1 also includes a piece of seating a seat support, a seat hinged to the seat support part and a back supported on a back support known part, the support force of the back part change is derbar. What is important with this seating is further  provided that the seat part by means of a parallelo Gram handlebar arrangement against the biasing force of a spring elements is adjustable in height mounted on the seat support and that the back support is pivotally mounted on the seat support is, with a pivoting movement of the back support ge against the biasing force of the spring element. Here is an automatic, body weight dependent Setting the resetting force of the tilt mechanism and the back part mechanics reached.

The disadvantage of this known seating furniture see that due to the storage of the seat part on a Parallelogram handlebar arrangement every movement in vertical direction inevitably leads to a simultaneous horizonta len offset leads. Since the Paral lelogram handlebars are approximately vertically aligned, is the ho at the beginning of a lowering movement of the seat part horizontal offset greater than vertical movement. The This horizontal offset of the seat part is for the user zer of the chair annoying and ergonomically unfavorable because thereby the distance of the back of the chair the person is changed from the backrest.

For the present invention, therefore, arises to create a chair of the type mentioned above, who avoids the disadvantages and with which independent adaptation with little design effort solution of the preload force of the backrest under different heavy users of the chair is reached without disturbing movements of parts of the chair occur.

This object is achieved in accordance with the invention by a chair of the type mentioned with the characteristics nenden features of claim 1.  

By the specified in the characterizing part of claim 1 he essential features of the chair are achieved, that the seat plate when used by a heavier Users straight forward and without a distracting simultaneous is moved downward towards the horizontal offset. This Movement of the seat plate down leads inevitably a tension of the compression spring assembly. Since the Compression spring arrangement on the backrest extension supports, the compression spring assembly exerts on the backrest support a lever moment that leads to an enlargement of the front load capacity of the backrest leads. A chair user with a higher body weight, a ver increased support of his back through the back lean as this is desirable and ergonomically sensible. If a lighter user in the chair sits, the seat plate takes a higher one Location one in which the compression spring assembly is less strong is tense; accordingly also results inevitably fig a lower preload of the backrest, so that a lightweight user is appropriate an appropriately low weight support from the backrest on his Back experiences. At the same time, however, the synchronizer remains Position of the seat plate and backrest in full received so that even when changing the seating position the seat plate and the backrest in a fixed Relationship to each other can be pivoted. Despite the syn chronomechanics and automatic adjustment of the back leaning preload to different users The chair's body weights are surprisingly one fold construction, so that the manufacture of the chair is relatively simple and inexpensive.  

To achieve a compact, take up little space the construction is preferably provided that the second Swivel axis near the longitudinal center of the seat plate below this runs. The required for the chair movements Liche mechanics can under the front half of the Seat plate are concentrated on what the manufacture of the Chair simplified and what an appealing look of the chair and in particular its under the Seat plate arranged movement mechanism results.

It is also provided that the seat plate on the underside at least one front and rear bearing support points through which the first, front and second tere pivot axis runs. Using these bearing supports get the first and the second pivot axis ge desired distance from the seat plate. You can also do so different seat plates in the simplest way the bearing supports are connected so that with little Effort different designs and designs of the chair with different seat plates are possible.

A technically simple and at the same time reliable Solution to achieve the vertical movement mentioned above play of the seat plate in relation to the seat support and / or the backrest carrier is that the camp zen each have an elongated hole through which one first, front and fixed to the seat support second, rear bearing bolt runs, the long holes on a radius around the not associated other bearing bolts. Through the mentioned Ver the slot is a swivel of the seat te both around the front, first pivot axis and around the rear, second pivot axis possible without jamming, see above that the seat plate has different seating positions of the chair user can adjust freely.  

It is also proposed that to form a backrest carrier movement stop the second, rear bearing bolt zen also by an essentially vertically aligned long slot runs in the backrest support. Separate funds to limit the movement of the backrest support saved this way, which is another contribution to ver simplification of the mechanical construction of the chair. At the same time, the slot mentioned serves in interaction with the second, rear bearing pin for coupling Seat plate and backrest swivel within the syn chronomechanics.

A version of the chair, which is preferred as an office shoot Chair can be used, provides that the seat support in Longitudinal direction of the seat plate in its transverse direction arranged below this and at its rear end connected to the chair column that left and right from the seat support symmetrical to this one backrest support provided with an associated compression spring arrangement is that there are two front and rear bearing supports those are and that a continuous front and back ter bearing pin is attached to the seat support.

An alternative version of the chair that is special is suitable as a meeting or conference chair characterized in that the seat support in two parts executed and in the longitudinal direction of the seat plate fend arranged on the left and right below this and one at each of its front and rear ends Chair leg is connected to the left and right inside of the two seat support parts parallel to each one Backrest support with an associated compression spring arrangement voltage is provided that two front and rear La are supported and that a continuous front and rear bearing bolts on the two seat supports gerteile is appropriate.  

The compression spring arrangement mentioned is preferably one Coil spring arrangement because coil springs have little on require installation space and because they are common and correspond easily available in various designs res component.

Instead of a coil spring arrangement, the Compression spring arrangement, for example, also a leg or gas pressure or elastomer spring arrangement.

Finally, the invention provides that the seat support and at least the one below the seat plate Part of the backrest support and, if applicable, the bearings support stamped and pressed parts are made of sheet steel. Stamping and pressed parts made of sheet steel are particularly inexpensive can be mass produced in large numbers where with it at the same time a high stability and durability show speed. This makes it high and permanent Quality of the chair with low manufacturing costs and guaranteed with low wear.

Two embodiments of the invention will follow that explained with the aid of a drawing. The figures of the Show drawing:

Fig. 1 a swivel chair seat in a first embodiment as an office, in side view,

Fig. 2 shows the chair of Fig. 1 in a bottom view and

Fig. 3, the chair in a second embodiment as a conference chair, also in side view.

In Fig. 1 as the first embodiment shown te office swivel chair 1 has as essential parts a seat plate 2 , a seat support 3 , a backrest support 4 with a backrest 4 'and a central chair column 5 with a base 50 at its lower end.

The seat plate 2 is a plate which is stable in itself and which can be provided on the upper side with a cushion, not shown here. On the underside, the seat plate 2 is connected to two front bearing supports 21 and two rear bearing supports 22 . The bearing supports 21 , 22 of each pair of supports are arranged one behind the other in the Seitenan view shown in FIG. 1, so that only one of the bearing supports 21 , 22 is visible. The front bearing supports 21 are arranged near the front edge of the seat plate 2 and each have an elongated hole 21 'through which a first bearing pin 31 runs horizontally and transversely. This first bearing pin 31 is fixedly connected to the seat support 3 , which in turn is fixedly connected to the upper end of the central chair column 5 by means of a chair column holder 30 .

The rear, second bearing supports 22 also each have an elongated hole 22 'through which a second Lagerbol zen 32 runs. This second bearing pin 32 is also firmly connected to the seat support 3 and runs parallel to the first bearing pin 31 . The elongated hole 22 'in the second bearing supports 22 runs on a radius around the first, front bearing pin 31 ; the elongated hole 21 'in the front bearing supports 21 runs on a radius around the second bearing pin 32 . In this way, ei ne movement of the seat plate 2 in the vertical direction relative to the seat support 3 is possible, this vertical movement can take place both approximately in a straight line downward and in the form of pivoting around the first, front bearing pin 31 or around the second, rear bearing pin 32 .

The backrest 4 'carrying backrest support 4 is formed in the illustrated embodiment by two backrest support parts 40 , 40 '. The backrest support part 40 runs below the seat plate 2 ; at its rear end, this is connected to the second backrest support part 40 'in the form of a plug-in connection which enables a height adjustment of the second backrest support part 40 ' and the backrest 4 'attached to it.

The extending under the seat plate 2 first Lehnenträ gerteil 40 is by means of a bore 43 and a bearing pin 33 , which is also firmly connected to the seat support 3 , pivotally mounted. Furthermore, the first backrest support part 40 has an extension 41 pointing forward over the bearing pin 33 , which runs parallel to the two other bearing pins 31 and 32 .

Finally, the chair 1 also comprises a Druckfederanord voltage, which is gebil det here by two helical compression springs 6 . The springs 6 are arranged one behind the other in the side view, so that only one spring 6 is visible in FIG. 1. With its upper end, the helical compression spring 6 is supported on the underside of the seat plate 2 , specifically in an area between the front bearing supports 21 and the rear bearing supports 22 . With its lower end, the helical compression spring 6 is supported on the forward-facing extension 41 of the first backrest support part 40 , as a result of which the helical compression spring on the one hand on the seat plate 2 has an upward biasing force and on the other hand via the first and the second backrest support part 40 , 40 ' exerts a forward bias force on the backrest 4 '.

In Fig. 1 the chair 1 is shown in a relieved To, in which no forces are exerted by a user of the chair 1 on the seat plate 2 and on the backrest 4 '. The pivot position of the backrest support 4 is limited in this position by an impact, which is formed by an elongated hole 42 in the first backrest support part 40 . With this elongated hole 42 of the second bearing bolt 32 extends, in which case the bearing pin 32 at the lower end of the slot 32 abuts.

If the chair 1 is loaded by a user, the seat plate 2 - depending on the body weight of the user - moves more or less far down. When the seat plate 2 is loaded by a heavier user, the spring arrangement 6 is compressed more and thus receives a higher tension. As a result, the Federanord voltage 6 exerts a greater force on the extension 41 of the first backrest support part 40 , which inevitably leads via lever action that the backrest 4 'receives a higher preload force to the front, that is to say supports the back of the user with a higher force. In the case of a lightweight user of the chair 1 , the seat plate 2 is pressed down correspondingly less, as a result of which the spring arrangement 6 is also less tensioned and as a result the backrest 4 ′ then also experiences a lower preload force. The preloading force or supporting force of the backrest adapts itself automatically to users of different weights.

In addition, the chair 1 offers a synchronous mechanism, which allows the position of the seat plate 2 and backrest 4 'to be coupled to one another. When a user leans back on the chair 1 , the seat plate 2 is lowered at the rear, with the backrest 4 'being pivoted backwards over the lever effects which occur.

In addition, as is known and customary per se, the backrest 4 'can be pivoted about a horizontally transverse axis on the second backrest support part 40 ', which enables a further improved adaptation of the backrest 4 'to different users of the chair 1 . The chair column 5 is also of known and conventional design and is preferably height adjustable and sprung, so that the chair 1 offers a wide range of adaptations to different users, the adjustment of the preload force of the backrest 4 'advantageously automatically depending on the body weight of the user of chair 1 is done.

The bottom view of the chair 1 from FIG. 1 shown in FIG. 2 of the drawing illustrates the symmetrical arrangement of the mechanics of the chair 1 on both sides of the longitudinal central axis 10 of the chair. In the middle is the seat support 3 , which has at its rear end, on the right in FIG. 2, the chair column receptacle 30 for connection to the chair column 5 , which is not visible here. Transversely to the seat carrier 3 are to this the three mounting pins 31, 32, 33 fixed, parallel to each other in the transverse direction of the chair 1 under the seat plate. 2 The ends of the bearing bolts 31 and 32 lie in the front and rear bearing supports 21 , 22 and run through the elongated holes 21 ′, 22 ′ provided therein and described in FIG. 1.

Further shows the Figure 2 that the first backrest support is designed in part 40 in two parts with two parallel, ten parallel to the longitudinal center axis 10 Abschnit The two portions of the first backrest support part 40 are Gert pivotable gela to the third bearing bolt 33..; in front of the third bearing pin, ie to the left in FIG. 2, are the extensions 41 of the two sections of the first backrest support part 40 . On these extensions stanchions 41 , the two helical compression springs 6 are supported with their lower end, which is turned towards the viewer here. With its upper end facing away from the viewer, the helical compression springs 6 are supported on the underside of the seat plate 2 facing the viewer.

On the far right in Fig. 2 it can be seen that here the second backrest part 40 ', not shown, with the backrest 4 ' can be connected by plugging in with the two sections of the first backrest part 40 .

Overall, FIG. 2 illustrates the very compact construction of the mechanics of the chair 1 , which results in a simple manufacture and a compact design. The various, for the movements of Sitzplat te 2 and backrest support 4 with the backrest 4 'required union pivot axes 71 , 72 , 73 are formed by the bearing bolts 31 , 32 , 33 , this construction being as stable as it is closable.

Fig. 3 of the drawing finally shows as a second exemplary embodiment from a conference or meeting chair 1 , which now has four chair legs 5 'instead of the central chair column, wherein only the chair leg facing the viewer can be seen in the side view shown in Fig. 3.

This version of the chair 1 includes a stable seat plate 2 with a cushion 20 , wherein on the underside of the seat plate 2 again the vorde ren and the rear bearing supports 21 , 22 with their elongated holes 21 ', 22 ' are available. The chair legs 5 'are rigidly connected to one another via the seat support 3 . Again, the three bearing bolts 31 , 32 , 33 are present, which in turn are firmly connected to the seat support 3 .

The backrest support 4 is designed to be continuous and carries the backrest 4 'on its upper part 40 '. The underlying the seat plate 2 part 40 of the Leh nenträgers 4 is mounted around the bearing shaft 33 pivotably on the seat carrier. 3 Here, too, the second, rear bearing bolt 32 runs through an elongated hole 42 in the backrest support part 40 in order to limit its pivoting path.

The backrest support 4 also has an extension 41 here, which extends forwards over the pivot axis 33 . On the extension 41 , the Druckfederanord voltage 6 is supported with its lower end, the upper end of which also lies on the underside of the seat plate 2 .

With regard to the movements of the seat plate 2 and backrest support 4 with backrest 4 ', the chair 1 behaves according to FIG. 3 like the chair 1 according to FIGS. 1 and 2; here, too, there is an automatic adjustment of the preload force of the backrest 4 'to the body weight of the user of the chair 1 . In addition, in the chair 1 according to FIG. 3, the synchronous mechanism for the coupling th pivoting of the seat plate 2 and backrest support 4 with backrest 4 'is ensured. A total height adjustment, as is possible through the chair column 5 in the chair 1 according to FIG. 1, does not have the chair 1 according to FIG. 3. A separate height adjustment of the backrest 4 'is also not provided for the chair 1 according to FIG. 3. Since this simplifies the individual parts of the chair 1 according to FIG. 3, the chair 1 can be manufactured particularly inexpensively in this embodiment. At the same time, it offers the user a high level of comfort through the synchronous mechanism and through the automatic adjustment of the preload force of the backrest 4 'depending on the body weight of the respective user. In addition, since the entire mechanism when the chair 1 according to Figure 3 below the seat plate 2 is very compact., Also this chair 1, as conventional rigid chairs can be known, to be stacked for storage and transport purposes, resulting in a very space saving arrangement.

Claims (10)

1. Chair ( 1 ) with a seat plate ( 2 ), with a seat plate ( 2 ) carrying seat support ( 3 ), which is connected to a central chair column ( 5 ) or several chair legs ( 5 '), and with a backrest support ( 4 ), which runs backwards under the seat plate ( 2 ) and upwards behind the seat plate ( 2 ) and carries a backrest ( 4 '), the seat plate ( 2 ) near its front edge about a horizontally transverse first pivot axis ( 71 ) can be pivoted to the seat support ( 3 ) and offset from it rearward about a parallel second pivot axis ( 72 ) pivotally to the backrest support ( 4 ), the backrest support ( 4 ) about a between the first and second pivot axes ( 71 , 72 ) parallel to this third pivot axis ( 73 ) is pivotally articulated to the seat support ( 3 ) and under the seat plate ( 2 ) a compression spring arrangement ( 6 ) supported on this is provided, which on the seat plate ( 2 ) one upwards n and exerts a forward biasing force on the backrest ( 4 '), characterized in that
that the backrest support ( 4 ) has an extension ( 41 ) pointing beyond the third pivot axis ( 73 ) and forming a lever arm, that the compression spring arrangement ( 6 ) is supported with its end remote from the seat on the backrest extension ( 41 ) and
that the seat plate ( 2 ) relative to the seat support ( 3 ) and / or the backrest support ( 4 ) has a vertical movement movement. 2. Chair according to claim 1, characterized in that the second pivot axis ( 72 ) near the longitudinal center of the seat plate ( 2 ) runs below this. 3. Chair according to claim 1 or 2, characterized in that the seat plate ( 2 ) on the underside has at least one front and rear bearing support ( 21 , 22 ) through which the first, front and second, rear pivot axis ( 71 , 72 ) runs. 4. Chair according to claim 3, characterized in that the bearing supports ( 21 , 22 ) each have an elongated hole ( 21 ', 22 ') through which a fixed to the seat support ( 3 ) connected to the first, front and second, rear Bearing pin ( 31 , 32 ) extends, the elongated holes ( 21 ', 22 ') running on a radius around the respective other not corresponding bearing pins ( 32 , 31 ). 5. Chair according to claim 4, characterized in that to form a backrest support movement stop, the second, rear bearing pin ( 32 ) also extends through a substantially vertically aligned slot ( 42 ) in the backrest support ( 4 ). 6. Chair according to claim 4 or 5, characterized in that the seat support ( 3 ) in the longitudinal direction of the seat plate ( 2 ) arranged in the transverse center below this and at its rear end with the chair column ( 5 ) is connected that left and to the right of the seat support ( 3 ) symmetrically to this, a backrest support ( 4 ), each with an associated compression spring arrangement ( 6 ), is provided, that two front and rear bearing supports ( 21 , 22 ) are available and that a continuous front and back terer bearing pin ( 31 , 32 ) on the seat support ( 3 ) is introduced. 7. Chair according to claim 4 or 5, characterized in that the seat support ( 3 ) made in two parts and arranged in the longitudinal direction of the seat plate ( 2 ) extending laterally to the left and right below this and at its front and rear ends with a chair leg ( 5 ') is connected that on the left and right inside of the two seat support parts ( 3 ) parallel to each one backrest support ( 4 ) is provided with an associated compression spring arrangement ( 6 ) that two front and rear bearing supports ( 21 , 22 ) are available are and that each run through the front and rear bearing bolts ( 31 , 32 ) on the two seat support parts ( 3 ) is attached. 8. Chair according to one of the preceding claims, characterized in that the compression spring arrangement ( 6 ) is a coil spring arrangement. 9. Chair according to one of claims 1 to 7, characterized in that the compression spring arrangement ( 6 ) is a leg or gas pressure or Elastomerfederanord voltage. 10. Chair according to one of the preceding claims, characterized in that the seat support ( 3 ) and at least the underneath the seat plate ( 2 ) extending part ( 40 ) of the backrest support ( 4 ) and optionally the bearing supports ( 21 , 22 ) punching and pressed parts are made of sheet steel.