EP1209994B1 - Chair - Google Patents

Abstract

This invention concerns a chair with a seat panel, with a central column or several legs and with a backrest carrier. In order to provide a tilting movement, the front of the seat panel rests on a horizontal, crosswise running first pivot and, in order to provide a tilting movement, the rear of the seat panel is attached to the backrest carrier around a second pivot. The backrest carrier is attached to the central column or the legs around a third pivot. The springs are arranged so that they exert an upward force on the seat panel and a forward force on the backrest. An arrangement of springs is provided that has at least one gripped spring, comprising bent spring-steel rod or wire, attached to the central column or the chair legs with at least one first and one second leg of the spring. The spring is hinged to the seat panel and supports the seat panel with one or more spring sections, and, at the same time, forms the first pivot. Further, the spring rests on the seat panel and on the backrest carrier and is pre-stressed in such a way that it exerts an upward force on the seat panel and a forward force on the backrest via the backrest carrier.

Description

The present invention relates to a Chair with a seat plate by one central chair column or several chair legs is worn, and with a backrest, the under the seat back and behind the seat Seat plate runs up and a backrest carries, with the seat plate close to her Leading edge around a horizontally transverse first pivot axis is pivotally mounted, with the seat plate close to its trailing edge a parallel second pivot axis pivotable is hinged to the backrest support, wherein the Lean support around one between first and second Swivel axis parallel to this running third pivot axis pivotable at the central Chair column or the chair legs articulated is, wherein a spring arrangement is provided, the at least one of a bent spring steel rod or wire existing spring with at least ever includes a first and second spring leg, being the spring with one or more Spring sections hinged to the seat plate is connected and at the same time the first pivot axis forms, and wherein the spring on the one hand the seat plate and on the other hand on the backrest support so supported and so biased that put it on the seat plate an upward facing Force and on the backrest support a backrest exerts forward biasing force.

A chair of the type mentioned is known from DE-A-3741472 known. With this construction of the Chair is achieved a so-called synchronous mechanism, when the user reclines the chair with loading of the rear part of the seat plate this rear is lowered and at the same time the backrest to is pivoted at the rear, this pivoting against the force of the spring takes place. The swivel angle of the backrest is usually greater than the swivel angle the seat plate. The ratio of the swivel angle each other is due to the cooperating lever lengths established.

A disadvantage is considered in this known chair, that the biasing force of the backrest only from the strength of the spring assembly and of the at Construction of the chair depends on fixed leverage. A change in the biasing force of the Backrest can only be done manually, which is an undesirably high effort represents, especially if a chair of different and different users. In addition, it is not guaranteed that the user actually find the right setting, resulting in wrong and possibly even harmful to health Settings of the biasing force of the backrest result can.

For the present invention, therefore, the task, to create a chair of the kind mentioned above, which avoids the disadvantages presented and in particular an automatic adjustment of the preload force the backrest to different heavy users the chair is achieved and in which the constructive Effort and especially the number of required parts should stay low.

The solution of this problem is achieved by the invention a chair of the type mentioned above with the characterizing Features of claim 1.

By specified in the characterizing part of claim 1 essential to the invention Features of the chair will be additional for synchronous mechanism achieved that the seat plate at Use by a user against the force of the spring assembly according to the weight of the user moved down, which inevitably leads to a corresponding Increasing the tension of the spring assembly leads. There On the other hand, the spring arrangement on the backrest support supports, exerts the increased tension of the spring assembly on the backrest carrier an increased lever moment, to an increase in the biasing force of Backrest leads. A chair user with a higher one Body weight thus receives increased support his back through the backrest, as desired and ergonomically useful. If a lighter weight User sits on the chair, takes the seat plate an upper lying position, in which the spring arrangement less tense; correspondingly results inevitably a lower preload the backrest, so that a lightweight user according to his lower body weight also one reasonably lower support force through the backrest on his back. At the same time the remains Synchronous adjustment of seat plate and backrest in preserved in full, so that even with changes the seating position the seat plate and the backrest in pivoted at a fixed ratio to each other become. Despite the synchronous mechanism and the automatic Adjustment of the backrest preload force to different ones User body weights is the chair of a surprisingly simple construction, so that the Production of the chair in relation to the offered Functions is simple and inexpensive. Especially no separate seat support is needed because the spring assembly at the same time the seat plate near its front edge carries and swivels. The spring arrangement is easy by bending into the required shape too bring; a modification of the spring force is by change the material thickness of the spring steel rod or wire or by changing spring leg lengths easily possible.

To achieve a particularly flat, low height claiming Construction of the mechanism under the seat plate is preferably provided that the backrest support an over the third pivot axis pointing forward, one Lever arm forming extension and that the Spring is supported on the backrest extension and exerts a downward force on them. This design required for the chair movements Mechanics also offers a pleasing appearance of the chair and is in particular for use suitable for stackable chairs.

It is further provided that the spring arrangement by two in plan view, U-shaped curved springs is formed, the side by side mirror-symmetrical under the seat plate are arranged, wherein in each case the first U-spring leg pointing to the back of the chair column or the chair legs is clamped, the U-bow of the spring with the the seat plate connected spring section for the first Pivoting axis forms and wherein in each case the second U-spring leg supported on the extension of the backrest support is. These U-shaped springs are very special flat and are easy to produce as bending parts. The Use of two springs ensures a good distribution forces and avoids unwanted lateral Tilting movements of the seat plate.

A development of the embodiment set out above is that the two forming the spring assembly U-shaped bent springs into a one-piece, in Top view W-shaped bent spring are combined, the symmetrical to the longitudinal center axis of the seat plate below this is arranged. This reduces the Production and assembly costs in the production of See.

It is also proposed that on the chair column or the chair legs for each first spring leg one each Clamping fixture, preferably a clamping sleeve, fixed is appropriate. The determination of the spring is on this Way very simple and at the same time visually very inconspicuous.

An alternative embodiment of the chair provides that the backrest ends at the third pivot axis and that the spring behind the third pivot axis on the backrest support supported and an upward on this Exercise power. Also with this version of the Chair are achieved the above-mentioned functions, wherein here one changed in terms of their direction of action Spring arrangement can be used. This increases the technical Freedom in the manufacture of the chair and in particular in the selection of the springs to be used.

A development of the chair described above Is characterized in that the spring arrangement by two torsion springs, each with a coiled spring body and each two spring legs is formed, wherein the springs side by side mirror-symmetrical under the seat plate are arranged, wherein each of the spring body the surrounding the third pivot axis, wherein in each case the first spring leg supported on the seat plate facing forwards is and at its front end with the seat plate connected spring portion for the first pivot axis forms and wherein each of the second spring leg after is supported on the backrest pointing backrest. Torsion springs need a bit more height, can be but easier to influence in their spring characteristic and vote. In addition, they usually allow larger Spring travel and thus a higher comfort of the chair.

In a further embodiment, the two are advantageous Spring assembly forming torsion springs to a einstükkigen Double leg spring combined, symmetrical to the longitudinal center axis of the seat plate below this is arranged. This will again be a simplified Production and assembly of the chair mechanism achieved.

For the designs of the chair with leg springs is preferably provided that on the chair column or the Chair legs for each first spring leg one each Movement upwards limiting stop, preferably a stop plate, is firmly attached. Thereby a defined upper end position of the seat plate is set, when the chair is not used. An undesirable wide increase of the seat plate in the absence of load is so excluded.

Instead of the concretely described spring arrangements can Alternatively, other spring assemblies are used, provided they needed the necessary forces in the, apply force directions as described above.

For all chair designs is provided advantageous that on the underside of the seat plate at least two front Bearing supports through which the first pivot axis passes, and at least two rear bearing supports, through which runs the second pivot axis are mounted. The forces that occur when using the chair become so conveniently introduced into the seat plate and from this derived. It can also be changed easily Seat plate to be grown, which together with a just as simple exchange of cultivated back modifications allows the chair in a variety of forms.

Furthermore, the invention provides that the formation of the third pivot axis under the seat plate a rod or tubular bearing pin is arranged, the tight with the chair column or the chair legs is connected and on which the backrest support is pivotally mounted. Except for the formation of the third pivot axis this serves Bearing bolt as a cross strut of the chair, what its stability promotes, especially when running with four chair legs.

As explained above, the chair preferably has a combination of synchronous mechanism and weight-dependent backrest preload. For those users who use the synchronous mechanism Do not wish, the chair can alternatively Be executed that the articulation of the seat plate to the Backrest support and the second, rear pivot axis omitted are, causing the seat plate and the backrest support unsynchronized, that is independently pivotable are. Restrict the necessary technical changes on the omission of individual parts, in particular the rear bearing pin and the associated Bearing supports.

Figur 1

einen Stuhl in einer ersten Ausführung als Konferenzstuhl, in Seitenansicht,

Figur 2

den Stuhl aus Figur 1 in einer Unteransicht,

Figur 3

den Stuhl in einer zweiten Ausführung als Konferenzstuhl, ebenfalls in Seitenansicht,

Figur 4

den Stuhl aus Figur 3 in einer Unteransicht.

Figur 5

den Stuhl in einer dritten Ausführung als Bürodrehstuhl, in Teil-Seitenansicht, und

Figur 6

den Stuhl aus Figur 5 in einer Unteransicht.

Three embodiments of the invention are explained below with reference to a drawing. The figures of the drawing show:

FIG. 1

a chair in a first version as a conference chair, in side view,

FIG. 2

the chair of Figure 1 in a bottom view,

FIG. 3

the chair in a second version as a conference chair, also in side view,

FIG. 4

the chair of Figure 3 in a bottom view.

FIG. 5

the chair in a third version as an office swivel chair, in partial side view, and

FIG. 6

the chair of Figure 5 in a bottom view.

The illustrated in Figure 1 as the first embodiment Chair 1 has as essential parts a seat plate 2, a backrest support 4 with a backrest 4 ', four Chair legs 5 and a spring assembly 6. The chair legs 5 are left and right in pairs as one piece executed approximately U-shaped arc, the U-leg form the legs 5. The spring arrangement consists here a spring 6 passing through a bent spring steel bar is formed. The spring 6 is approximately in the bottom view W-shaped, as will be described with reference to FIG 2 becomes. Two lateral outer legs 62 of the spring 6 are fixed at its end in grommets 56, the fixed are connected to the chair legs 5.

The seat plate 2 is a stable plate in itself on the upper side with a pad, not shown here can be provided. On the underside, the seat plate 2 with four front bearing supports 21 and two rear bearing supports 22 connected. The bearing supports 21, 22 are at the side view shown in Figure 1 in succession arranged so that in each case only one of the bearing supports 21, 22 is visible. The front bearing supports 21 are near the left of the drawing Front edge of the seat plate 2 arranged and own one storage hole each. Through the front bearing supports 21, a front portion 61 of the spring 6 and thus forms a first pivot axis 71 for the seat plate Second

The rear, second bearing supports 22 also have each a bearing hole through which a bearing pin 32 in Chair transverse direction runs horizontally. In addition, runs this second bearing pin 32 through the backrest carrier 4 and forms with this a pivot joint with a second pivot axis 72, which is parallel to the first pivot axis 71 runs.

The backrest 4 'supporting backrest support 4 is in one piece by an approximately right-angled profile, e.g. a pipe formed. The backrest support 4 initially runs below the seat plate 2 to the rear and bends then upwards. At its upper end is the backrest support 4 connected to the backrest 4 '.

The running under the seat plate 2 first section of the backrest support 4 is by means of a bearing sleeve 33 'and a bearing pin 33 fixed to the chair legs. 5 is connected to a third pivot axis 73, which is parallel to the other pivot axes 71, 72 runs, pivotally mounted. Furthermore, the backrest support 4 a pointing over the bearing pin 33 forward Extension 41 on. With her second, from the spring section 61 rearwardly facing spring leg 64 is the spring 6 on the upper side of the forward facing extension 41 of the first back support member 40 supported. The spring 6 is biased so that they on the one hand the seat plate 2 an upward biasing force and on the other hand on the backrest support 4 on the Backrest 4 'is a forward biasing force exercises. At the same time, the chair 1 is a movement the seat plate 2 in the vertical direction relative to the Chair legs 5 possible, this vertical movement both approximately straight-line vertically as well as in the form of Verschwenkungen about the first, front pivot axis 71st or around the second, rear pivot axis 72 can.

In the figure 1, the chair 1 is in a discharged state shown in which on the seat plate 2 and on the backrest 4 'no forces by a user of the Chair 1 are exercised. The pivoting of the backrest carrier 4 forward is in this position by a limited visible stop.

If the chair 1 is loaded by a user, moves the seat plate 2 - depending on the body weight of the user - more or less far down. Under pressure the seat plate 2 by a heavier user becomes the spring 6 in its section 61 bent more downwards and thereby receives a higher voltage. Thereby exercises the spring 6 with its spring leg 64 a correspondingly greater downward force on the extension 41 of the backrest part 40, which is about leverage inevitably leads to the fact that the backrest 4 ' receives a higher biasing force forward, so supports the user back with a higher force. For a more lightweight user of chair 1 will the seat plate 2 correspondingly less pressed down, whereby also the spring 6 is tensioned less and which then also the backrest 4 'a smaller Preload experienced. The preload force or Supporting force of the backrest 4 'thus fits automatically to different heavy users.

In addition, the chair 1 provides a synchronous mechanism, the it allows the position of seat plate 2 and backrest 4 'coupled with each other to change. If a user on the chair 1 leaning backwards, the Seat plate 2 lowered against the force of the spring 6 back, at the same time the backrest 4 'on the thereby occurring leverage in a fixed swing angle ratio is pivoted to the rear.

As an alternative to the embodiment shown, as such known, the backrest 4 'to a horizontal transverse Axis pivotally mounted on the backrest support 4 what a further improved adaptation of the Backrest 4 'to different users of the chair 1 allows.

The bottom view shown in Figure 2 of the drawing of the chair 1 of Figure 1 illustrates the symmetrical Arrangement of the mechanics of the chair 1 on both sides of the Longitudinal axis 20 of the seat plate 2, in the background is visible. In the middle is parallel to the axis 20th the backrest support 4, at its rear, in Figure 2 upper end, the backrest 4 'carries. Cross to the backrest 4, the two bearing pins 32, 33, the extend parallel to each other in the transverse direction of the chair 1 below whose seat plate 2 run and the second and third pivot axis 72, 73 form. The ends of the back, shorter bearing bolt 32 are in the rear Bearing supports 22, both sides of the backrest support 4 at the seat plate 2 are attached; the ends of the middle one Bearing 33, which extends over the entire width of the seat plate 2 ranges are on two lateral bearing plates 53rd fixed, which is firmly connected to the chair legs 5 are.

The backrest support 4 is on the central bearing pin 33rd by means of a bearing sleeve 33 'about the pivot axis 73 pivotally stored; in front of this bearing pin, i. in figure 2 under this, is the extension 41 of the backrest carrier 4. On this extension 41 is based Spring 6 with their central spring legs 64 from. With its two lateral outer spring legs 62 is the spring 6 is held in the lateral gripping sleeves 56, which are fixedly attached to the chair legs 5. The near the front edge of the seat plate 2, in the drawing lying below sections 61 of the spring 6 run transversely to the axis 20 through the four front bearing supports 21 and form the first pivot axis 71st

Figure 2 clearly shows the very simple and clear Construction of the mechanics of the chair 1, which itself a simple manufacturability and a compact size result. The construction is both stable as well as wear-resistant. In addition, the chair 1 is included Non-use space-saving stackable, which so far only with simple chairs without synchronous mechanism and without automatic weight adjustment of the backrest force was possible.

Figures 3 and 4 of the drawing show second Embodiment another conference chair 1, the in contrast to the chair according to FIGS. 1 and 2 equipped with two springs 6 and two backrests 4 is.

This embodiment of the chair 1 includes a in itself stable seat plate 2, being at the bottom of the seat plate 2 here four front and rear bearing supports 21, 22 are present. The chair legs 5 are over the a cross-beam forming central bearing pin 33rd rigidly connected, the third at the same time Pivot axis 73 forms. Also here are two rear bearing pins 32 present, with their ends in the associated rear bearing supports 22 are fixed and the form the second pivot axis 72.

The backrest support 4 ends here at the central bearing pin 33rd and are rotatably mounted on a bearing pin 33 on this Bearing sleeve 33 'attached, e.g. welded. The Back support 4 here have none over the third Swivel axis 73 projecting extension. At her upper End wear the backrest support 4 back the backrest 4 '. The backrest 4 'and the backrest support 4 are therefore at the bearing pin 33 and the third pivot axis 73 pivotally stored. On the central bearing pin 33 is left and right outside next to the sleeve 33 'each of the coiled spring body 65 of the springs 6 is supported, the here are torsion feathers. Two first spring legs 62 extend from the spring body 65 forward and are there in Transverse direction of the seat plate 2 is bent and through the front bearing supports 21 out. These sections 61 The spring 6 thus also form the first pivot axis 71. Each two second spring legs 64 run from the spring body 65 back and are with their end on the backrest 4 supported behind the third pivot axis 73. The leg spring 6 is biased so that the first Leg 62 on the seat plate 2 a force upward and the second legs 64 on the backrest support 4 a Exercise force also upwards. The movement of the seat plate 2 up is through two side stops 57, which are firmly connected to the chair legs 5 and against the strike the first spring legs 62, limited.

Regarding the movements of seat plate 2 and backrests 4 with backrest 4 ', the chair 1 behaves according to Figure 3 and 4 as the chair 1 according to Figure 1 and 2; Here, too, is an automatic adjustment the biasing force of the backrest 4 'on the body weight In addition, it is also the user of the chair in the chair 1 according to Figures 3 and 4, the synchronous mechanism for coupled pivoting of seat plate 2 and backrest support 4 with backrest 4 'guaranteed. Because the whole Mechanics also in the chair 1 according to Figures 3 and 4 below the seat plate 2 is very compact, too this chair 1 stacked for storage and transportation purposes be, resulting in a very space-saving arrangement results.

Figures 5 and 6 of the drawing show an embodiment of chair 1, in which this as an office swivel chair, So with a central chair column 5, is executed. The central chair column 5 has at its upper end a head 51, through which the middle, third bearing pin 33 runs. To this bearing pin 33, the third pivot axis 73 forms is the backrest support 4th pivotable. At its upper, not visible here End carries the backrest support 4 back the backrest.

Furthermore, the chair 1 according to FIG. 5 and FIG 6 a seat plate 2, the lower side four front Has bearing supports 21 and two rear bearing supports 22. Finally, the chair 1 is a spring 6, which is similar here as in the example according to Figures 1 and 2. The spring 6 is what Figure 6 particularly clarified, in view W-shaped bent and mirror-symmetrical to the longitudinal central axis 20 of the seat plate 2 arranged under this. Also here has the spring 6 two front, extending in the transverse direction of the seat plate 2 Spring portions 61 passing through the front bearing supports 21 run and the first pivot axis 71 form. On the outside are two spring legs 62 of the spring portions 61 to the rear. With your rear part are the spring legs 62 in two lateral outer grommets 56 set. The clamping sleeves 56 are at the outer end of two wings 52 firmly attached, in turn, firmly with the head piece 51 of the central chair column 5 are connected.

Two inner spring legs 64 extend from the spring sections 61 also backwards and are in theirs End area integrally connected to each other. In this Area support the spring legs 64 on top the extension 41 of the backrest support 4 from. The spring 6 is biased so that it on the seat plate 2 a upward force and extension 41 of the backrest support 4 exerts a downward force. The downward, on the extension 41 of the backrest support 4 exerted force causes a preload the backrest towards a user of the chair.

In terms of its function, the chair corresponds to Figures 5 and 6 the previously described embodiments according to the figures 1 to 4. Also here is So an automatic adjustment of the preload force the backrest depending on the weight of the user reached the chair 1. At the same time here is one Synchronous mechanism in the movement of seat plate 2 and Backrest support 4 given. As particularly the figure 5 illustrates, is also in the execution of the chair 1 as Office swivel chair the mechanism below the seat plate 2 very compact and requires only a small height as well only a few items.

Claims (12)

1. Chair (1) comprising a seat plate (2) that is supported by a central chair column or several chair legs (5) and comprising a backrest base (4) that is extending underneath the seat plate (2) in a backward direction and behind the seat plate (2) in an upward direction and is carrying a backrest (4'), wherein the seat plate (2), near its front end, is mounted such that it can be pivoted about a first swivel axis (71) that extends horizontally in a transverse direction, wherein the seat plate (2), near its rear end, is mounted to the backrest base (4) such that it can be pivoted about a parallel second swivel axis (72), wherein the backrest base (4) is mounted to the central chair column or the chair legs (5) such that it can be pivoted about a third swivel axis (73) that extends between the first and second swivel axes (71, 72) and in parallel thereto, wherein a spring arrangement is provided that comprises at least one spring (6) that consists of a bent spring steel bar or wire and is provided with at least one first and one second spring leg (62, 64), wherein the spring (6) is pin-connected to the seat plate (2) with one or more spring sections (61) and, at the same time, forms the first swivel axis (71), and wherein the spring (6) is supported against the seat plate (2) on the one hand and against the backrest base (4) on the other hand and is biased such that it exerts on the seat plate (2) a force that acts upwards and on the backrest base (4) a force that preloads the backrest (4') in a forward direction,
   characterized in that

   the spring (6) is mounted to the central chair column or the chair legs (5) in a gripping manner,

   the chair (1) is designed without a seat base, and

   the spring (6) forms the only support of the seat plate (2) within the area of the first swivel axis (71).
2. Chair according to claim 1, characterized in that the backrest base (4) comprises an extension (41) that forms a lever arm and extends beyond the third swivel axis (73) in a forward direction, and that the spring (6) is supported against the backrest base extension (41) and exerts a force that acts on the latter in a downward direction.
3. Chair according to claim 2, characterized in that the spring arrangement is formed by two springs (6) that are bent in the shape of a U as seen from above, with said springs (6) being arranged underneath the seat plate (2) side by side and mirror-symmetrically, wherein the first U-spring leg (62) is each mounted to the chair column or the chair legs (5) in a gripping manner such that it points to the rear, wherein the U-bend of the spring (6) forms the spring section (61) for the first swivel axis (71), with the spring section (61) being connected to the seat plate (2), and wherein the second U-spring leg (64) is each supported against the extension (41) of the backrest base (4).
4. Chair according to claim 3, characterized in that the two springs (6) that are bent in the shape of a U and form the spring arrangement are combined to form a single-piece spring (6) that is bent in the shape of a W as seen from above, with said W-shaped spring (6) being arranged symmetrically to the longitudinal central axis (20) of the seat plate (2) underneath the latter.
5. Chair according to claim 3 or 4, characterized in that one gripping holder (56), preferably one gripping sleeve, is each mounted to the chair column or the chair legs (5) in a non-removable manner for each first spring leg (62).
6. Chair according to claim 1, characterized in that the backrest base (4) ends at the third swivel axis (73) and that the spring (6) is supported against the backrest base (4) behind the third swivel axis (72, 73) and exerts on the latter a force that acts in an upward direction.
7. Chair according to claim 6, characterized in that the spring arrangement is formed by two leg springs (6), each comprising a helical spring element (65) and two spring legs (62, 64), wherein the springs (6) are arranged underneath the seat plate (2) side by side and mirror-symmetrically, wherein the spring element (65) each environs the third swivel axis (73), wherein the first spring leg (62) is each supported against the seat plate (2) while pointing to the front and, at its front end, forms the spring section (61) for the first swivel axis (71), said spring section (61) being connected to the seat plate (2), and wherein the second spring leg (64) is each supported against the backrest base (4) while pointing to the rear.
8. Chair according to claim 7, characterized in that the two leg springs (6) forming the spring arrangement are combined to form a single-piece dual leg spring that is arranged symmetrically to the longitudinal central axis (20) of the seat plate (2) underneath the latter.
9. Chair according to claim 7 or 8, characterized in that, for each first spring leg (62), a stop (57), preferably a stopper plate, is each mounted to the chair column or the chair legs (5) in a non-removable manner, said stop (57) limiting the movement of the first spring leg (62) in an upward direction.
10. Chair according to one of the preceding claims, characterized in that at least two front bearing supports (21) and at least two rear bearing supports (22) are attached to the seat plate (2) underneath the latter, with the first swivel axis (71) extending through the at least two front bearing supports (21) and the second swivel axis (72) extending through the at least two rear bearing supports (22).
11. Chair according to one of the preceding claims, characterized in that a bar-shaped or tubular bearing bolt (33) is arranged underneath the seat plate (2) to form the third swivel axis (73), wherein said bearing bolt (33) is connected to the chair column or the chair legs (5) in a non-removable manner, and wherein the backrest base (4) is pivoted to said bearing bolt (33).
12. Chair according to one of the preceding claims, characterized in that the pivoted attachment of the seat plate (2) to the backrest base (4) and the second, rear swivel axis (72) have been omitted and that the seat plate (2) and the backrest base (4) can be pivoted independently of each other in a non-synchronized manner.

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