HK1090264B - Chair - Google Patents

Description

Chair (Ref. now to FIGS)

Technical Field

The invention relates to a chair with a seat and a mechanism for adjustably fixing the angle of inclination of the seat to a seat support, which is connected to a central column.

This type of chair may be used in applications such as offices, meeting rooms, reception rooms, etc. The inclination angle of its seat and/or backrest can be adjusted.

Background

DE 4403123 a1 describes a synchronous adjustment device in which the ratio between the angle of inclination of the seat and the angle of inclination of the backrest can be adjusted. The synchronous adjustment mechanism is composed of a plurality of parts which are hinged with each other and an energy storage element (a spring is used in the process). The relatively complex and expensive synchronous adjustment mechanism of the known type is relatively expensive due to the use of numerous components and parts, and the service life of the known adjustment mechanism is limited due to the use of moving parts which are subject to wear.

DE 29704906U 1 describes a seat with a synchrotilt mechanism, in which the seat surface is fastened to the seat post by means of a first elastically deformable element and the backrest is fastened by means of a backrest support to a second elastically deformable element connected to the first elastic element. Furthermore, the first spring element or seat surface is connected to the second spring element or backrest carrier in a spring-like manner or in an articulated manner. This avoids the above-mentioned disadvantages of previous mechanisms for synchronous adjustment, in particular the long service life and the low operating noise that can be achieved during actuation. Of course, this solution still uses numerous mechanical parts, which results in high assembly costs and a high wear potential in use. Moreover, it does not allow free, continuous relative adjustment of the seat surface and the backrest.

Disclosure of Invention

The object of the invention is to improve a chair of the type mentioned at the outset, in such a way that as few mechanical moving parts as possible are required, that the synchronous adjustment and optionally the adjustment of the seat support and backrest can be achieved in a simple manner, and that the movement sequence of the adjustment is continuous and lighter than hitherto.

This object is achieved by a chair having a seat and a mechanism for adjustably fixing the angle of inclination of the seat to a seat support connected to a central column, wherein the mechanism comprises a knee lever arrangement. The tilting movement can be adjusted in any way and continuously thanks to the use of a knee lever structure, and the movement is very light. In particular, complicated mechanical spring elements and wear-prone gear changes and transmissions are completely eliminated.

The curved bar structure comprises a first connecting rod fixed on a fixed middle shaft on the seat and a second connecting rod hinged on a third rotating shaft fixed on the seat support, the two connecting rods are mutually hinged on a movable fourth rotating shaft, and a mechanical structure for connecting the fourth rotating shaft with the seat is also arranged. The seat and the seat support are then connected to each other in a simple manner.

The seat is adjusted in inclination in relation to the compression of the rear seat part, and to influence the degree of inclination, the fourth shaft is connected via a telescopic element and a further connecting rod to a torsion bar, wherein the further connecting rod is connected in a rotationally fixed manner to the torsion bar.

In a simple embodiment, the telescopic structure is designed as a pin which can be inserted into the receptacle against the force of a compression spring.

In order to adjust the angle of inclination of the seat back, a set of mechanisms for backrest inclination adjustment may be additionally provided on the seat.

A good inclination adjustment can be achieved in that the backrest is connected via a backrest support to a slide which is mounted so as to be slidable on the seat, wherein the backrest can be laterally fixed on the seat.

Preferably, an arc-shaped lever is provided which supports the slide, so that an adjustment of the angle of inclination of the backrest into a comfortable rest position can be achieved.

The two sides of the seat can be respectively provided with a sliding block, the sliding blocks are mutually opposite, and the two sliding blocks are respectively fixed with the middle shaft through a connecting element. The movement of the two slides is also synchronized.

In order to achieve a synchronous inclination adjustment of the seat and the backrest, the first link of the knee lever arrangement and the rotatable central shaft are connected in a rotationally fixed manner, so that the central shaft is rotated by the first link when the seat is lowered, so that the slide is moved rearward by the connecting element. Whereby the backrest sinks rearward integrally with the seat. The angle between the first link and the two connecting elements, both fixed to the central axis, determines the degree to which the backrest, together with the seat, sinks down.

To limit the tilting of the backrest, an air spring can be provided to limit the sliding block.

Drawings

The following figure schematically shows a preferred embodiment of the invention and is described in connection with the accompanying drawings. The attached drawings are as follows:

FIG. 1: a perspective view of the seat;

FIG. 2: a seat perspective view of the chair without the seat cushion;

FIG. 3: FIG. 2 is a cross-sectional view of the seat taken along line III-III;

FIG. 4 a: a side view of the seat with the seat and backrest not reclined;

FIG. 4 b: FIG. 4a is a partial enlarged view of a side view;

FIG. 5 a: a side view of the seat with the seat and backrest tilted;

FIG. 5 b: FIG. 5a is a partial enlarged view of a side view;

Detailed Description

In fig. 1, the structure of a chair 1 can be seen, which basically comprises a backrest 2, a seat 3 and a central upright 4, which is connected to a base, not shown in the figures, which is slidable by means of rollers.

The seat 3 has a shell shape with a flat middle part 5 and two side walls 6 mounted laterally and projecting in the direction of the backrest 2. The seat 3 is arranged on the central upright 4 by means of a seat support 7.

The backrest 2 is connected to the side wall 6 via two L-shaped backrest brackets 8 arranged transversely to the backrest 2, one arm 8a of the bracket 8 being fixed to the backrest 2 and the other arm 8b being movably articulated to the side wall 6. Due to the L-shape and the lateral arrangement of the backrest support 8, a distance is provided between the backrest 2 and the rear region of the seat 3 below the lower region 9 of the backrest that is oriented toward the seat. The arm 8b is also spaced from the rear region of the seat.

The backrest support 8 laterally encloses the rear seat part and can be used as an armrest. The backrest 2, the seat 3 and the backrest support 8 are all covered with cushions 10a to 10 c.

Figure 2 clearly shows the seating form with a flat middle piece 5 and upwardly projecting side walls 6 for accommodating the mechanism for simultaneous adjustment of the seat and back rest inclination.

The arm 8a of the backrest support 8, not shown in fig. 2, is fixedly connected to a slide 11, which slide 11 can slide on an arc-shaped bar 12 of circular cross-section, so as to bring the backrest into a vertical basic position and into a tilted rest position. The two inner sides of the backrest bracket hinged on the side wall 6 are the same. In order to synchronize the movement of the two sliding blocks 11, they are each connected to a rotatable central shaft 14 via a connecting element 13. The movement of the slide 11 is such that the slide 11 and thus the backrest automatically return to the basic position, respectively, against the spring force of the tension spring 15. An air spring 16 connected to the connecting element 13 is provided for arresting the slider 11. If there is sufficient pressure in the air spring 16, the movement of the connecting element 13 and thus the further displacement of the slider 11 is prevented.

The central axis 14 is also the part of the link between the backrest tilt adjustment and the seat tilt adjustment. A set of curved rod structures 17 is arranged on the central shaft 14, and the curved rod structures can realize the functions of adjusting the inclination of the seat 3 and the seat support 7 and can control the inclination adjustment according to the weight distribution of the tail part of the seat. The other side of the knee lever arrangement 17 is connected to a torsion bar 18, the ends of the torsion bar 18 being fixedly supported on the seat 3 and forming the axis of rotation of the seat 3.

In fig. 3 it can be seen that the knee lever arrangement 17 comprises a first rotary shaft, which is formed by the central shaft 14 and is stationary in the seat 3, a second rotary shaft, which is formed by the torsion bar 18 and is stationary in the seat 3, a third rotary shaft 19, which is stationary in the seat support 7, a fourth movable rotary shaft 20 and a fifth movable rotary shaft 21.

The first link 22 is arranged on the central shaft 14 in a rotationally fixed manner and is connected via a fourth pivot 20 to a second link 23, the second link 23 being mounted in an articulated manner on the seat carrier 7. When the seat 3 is subjected to a pressure load in the direction 24 indicated by the arrow, the links 22 and 23 move relative to each other about the pivot axis 20 and push the pin 26 into the receiving member 25 against the spring force of the pressure spring 27. This force is in turn transmitted to the other link 28 causing it to deflect, thereby causing torsion in torsion bar 18 as the other link 28 is connected to torsion bar 18 in a torsionally stiff manner. By means of the pivot 29, the force for deflecting the connecting rod 28 can additionally be adjusted. Torsion bar 18 is used for seat 3 recovery when unloaded.

When the seat 3 is subjected to the weight in the direction of the arrow 24 and the rear part thereof sinks, the center shaft 14 is rotated by the first link 22 provided on the center shaft 14 in a torsion-proof manner. The connecting element 13 and the slide 11 fixed thereto are thereby moved backwards, so that a synchronized tilt adjustment of the backrest and the seat 3 is obtained.

Fig. 4a to 5b show in sequence the tilting adjustment of the seat 3 and the backrest 2 from a basic position (fig. 4a and 4b) into a relaxed position (fig. 5a and 5 b). Possible weight transfers at the rear of the seat are indicated by arrows.

Claims (8)

1. A chair (1) having a seat (3) and a mechanism for the angularly adjustable fixing of the seat (3) to a seat support (7) connected to a central upright (4), which mechanism comprises a knee lever arrangement (17), which knee lever arrangement (17) comprises a first connecting rod (22) which is fixed to a stationary central shaft (14) on the seat (3) and a second connecting rod (23) which is articulated to a stationary third shaft (19) on the seat support (7), which two connecting rods (22, 23) are articulated to one another on a movable fourth shaft (20), wherein mechanical means (18, 25, 26, 27, 28) are provided for connecting the fourth shaft (20) to the seat (3), characterized in that the fourth shaft (20) is connected via a telescopic element (25, 26, 27, 28), 26. 27) and the further link (28) are connected to a torsion bar (18), while the further link (28) is connected to the torsion bar (18) but not torsionally movable relative thereto.

2. Seat according to claim 1, characterized in that the telescopic element is constituted by a pin (26) insertable in a housing (25) against the force of a compression spring (27).

3. Seat according to claim 1, characterized in that a mechanism for the inclination adjustment of the backrest (2) is provided.

4. Chair according to claim 3, characterized in that the backrest (2) is connected by means of a backrest support (8) with a slide (11) which is supported slidably on the seat (3).

5. Seat according to claim 4, characterized in that an arc-shaped bar (12) is provided which supports the slider (11).

6. Seat according to claim 4 or 5, characterized in that one of said sliders (11) on one side of the seat (3) is opposite the other slider (11), the two sliders (11) being each fixed to the central shaft (14) by a respective connecting element (13).

7. Seat according to claim 6, characterized in that the first link (22) of the knee lever arrangement (17) is connected in a rotationally fixed manner to the rotatable central shaft (14).

8. Seat according to claim 6, characterized in that an air spring (16) is provided to limit the movement of the slider (11).