DE20306685U1 - Folding chair, comprising movable joints at all corners in order to facilitate extremely flat folding - Google Patents

Abstract

The chair (1) is assembled of four legs (2, 3, 4, 5), each movable joined to the lateral seat parts (6, 7) and to a lateral positioned bottom bar (10, 11). Round transversal bars (8, 9, 18, 19) are positioned between the upper ends of the front legs (2, 4), the upper ends of the rear legs (3, 5), the lower ends of the front legs (2, 4) and the lower ends of the rear legs (3, 5). The lateral parts (13, 14) of the back rest are swivel mounted to the round transversal bar (9) at the rear of the seat area which is covered with a textile material (17). The joint areas (21, 22, 31, 32, 41, 42, 51, 52) are provided with stops. For storage the backrest is folded to the front and the upper transversal bar (8) at the front is moved towards the lower bar (9) at the back, resulting in a completely flat shape.

Description

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P28149DE

Folding chair l

The invention relates to a folding chair.

The aim of folding chairs is to be able to be folded up in a way that saves space and is as stackable as possible. On the other hand, folding chairs must have a construction that is secured against accidental folding so that the user is not endangered. The aim of the invention is therefore to create a folding chair that, in addition to the technical requirements of good foldability, stackability and safety, is easy to handle and also has an attractive appearance.

This object is achieved with a folding chair which, according to the invention, has the features mentioned in patent claim 1.

Advantageous embodiments of the invention emerge from the subclaims.

The folding chair according to the invention is designed in such a way that the chair legs are connected to support bars at their lower ends and, together with the chair legs and the two seat bars that connect the chair legs to each other at their upper ends, form four-bar joints. These four-bar joints allow the folding chair to be folded into one plane. The backrest is designed in such a way that it can be rotated between the seat bars. At least one joint on the right chair legs and one joint on the left chair legs have a limited degree of rotation in order to provide stability when unfolded. The chair is stabilized by the weight of the user sitting on it.

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According to a special embodiment of the invention, the four-bar linkage is designed as a parallelogram, which gives the folding chair an attractive appearance. According to a further embodiment, the chair legs have cranked ends at diagonally opposite joints. This allows the front chair legs to rest on the support slats and the seat bars to rest on the rear chair legs, which are then aligned with the support slats, when the folding chair is folded up, so that the folding chair is very flat when folded up. According to another embodiment, the support slats and the seat bars can be arranged on the inside of the chair legs, so that when folded up, the chair legs and the seat slats or the seat bars lie next to one another, with the backrest then being pivoted between the seat bars, so that when folded up, the folding chair only has a very small surface area, which is determined by the width of the chair legs or the support slats.

In the following, the invention is described and explained in more detail using the embodiment shown in the figures.

Show it: 1 figure 2 figure 3 figure 4 figure 5 A-F figure 6 figure

a perspective view of the folding chair in

unfolded state;

a view of the folding chair from the right in the unfolded state;
Figure 3 is a plan view of the unfolded folding chair exactly from

above;

a view of the folding chair directly from the front;

the process of folding;

in detail one of the joints of the folding chair with rotation angle limitation;

Figure 7 shows another joint.

According to Figure 1, the folding chair consists of a right and a left four-bar linkage, whereby the right four-bar linkage is formed from the front chair leg 2 and the rear chair leg 3, the support bars 10 connecting their lower ends and the seat bar 6. The left four-bar linkage consists of the front chair leg 4, the rear chair leg 5, the support bar 11 and the seat bar 7. The front upper ends of the front chair legs 2, 4 are connected to a front cross bar 8 and the upper ends of the rear chair legs 3, 5 are connected to a rear cross bar 9. The connections of the chair legs 2, 3, 4, 5 to the support bars 10, 11 and the seat bars 6, 7 are designed as joints 21, 22, 31, 32, 41, 42, 51, 52. A cloth is stretched between the front crossbar 8 and the rear crossbar 9 as a seat surface 17. The backrest consists of a right support 13, a left support 14 and a cross brace 15, with a cloth also stretched between the supports 13, 14 as a leaning surface 16. The supports 13, 14 of the backrest are preferably bent backwards at their ends so that the cross brace 15 is offset backwards. The lower ends of the front chair legs 2, 4 are connected by a front cross brace 18, the lower ends of the rear chair legs 3, 5 are connected by a rear cross brace 19, so that an oblique parallelepiped is formed which is very stable since the chair legs cannot move against each other when set up.

The joints 21, 32, 41, 52, where the chair legs form an acute angle with the associated seat bars and slats, have a rotation limiter by means of a stop. The weight of the user sitting on them exerts a force in the direction of the stop, so that the parallelepiped becomes stable.

In Figure 2, the chair is shown in a view from the right. The front leg 2 of the chair uses a cranked lower end 24, whereby the angle α between the cranked end and the long part 23 is approximately 110°. Other values for the angle α are also possible, but it must be greater than 90°. Accordingly, the angle ß by which the leg 2 of the chair is inclined forwards against the vertical when it is in the upright position is approximately 70°, or 180° - α.

The rear chair leg 3 is also cranked, and is arranged rotationally symmetrically to the front chair leg 2, so the chair leg 3 is cranked at the upper end 34. The angle α between the cranked end 34 and the long part 33 is just as large as for the front chair leg and is 110° in the example mentioned. The design of the joints 21, 22, 31, 32 of the front and rear chair legs is limited and corresponds to the angle α, so that after unfolding the chair legs are prevented by a stop from being rotated against the base bar 10 or the seat bar 6 by more than the angle α.

Figure 3 shows the folding chair in an upright position from above. It can be seen that the supports 13, 14 of the backrest are arranged on the inside of the seat bars 6, 7. Figures 2 and 3 also show that the cross brace 15 of the backrest is located in front of the lower ends of the rear chair legs 3, 5, so that the folding chair cannot tip backwards even if the user leans back and perhaps rocks the chair.

The cloth forming the seat surface 17 is provided with an opening 20 at its rear end, which is placed around the rear cross member 9, which enables the user to grasp and carry the chair in the folded state by the cross member 9.

Figure 4 shows the chair from the front.

Figures 5 A to F show the process of folding the folding chair. The seat back is rotated between the seat bars and at the same time or subsequently the chair legs are rotated towards the support bars so that the folding chair in the folded state is determined only by the width of the support bars or the chair legs.

Figure 6 shows a detail of the joint 32, which forms the connection between the right-hand support rail 10 and the right-hand rear chair leg 3, in a largely unfolded state. The lower end of the chair leg 3 and the rear end of the support rail 10 are each provided with a central slot 36, 60, which are dimensioned such that one of the two webs 35, 37 of the chair leg 3 located on the sides of the slot 36 fits into the slot 60 of the support rail 10, and likewise one of the two webs 65, 67 of the support rail 10 fits into the slot 36 of the chair leg 3. The joint axis can be formed by the rear cross brace 19. On the outside of the joint there is a decorative disc that covers the axis of rotation.

If, when setting up the chair, the chair leg 3 is pivoted from the folded state, in which the chair leg 3 and the support bar 10 lie in the same plane, in the direction of arrow A in Fig. 6 towards the support bar, after a rotation through the angle α the web 35 of the chair leg 3 hits the inner boundary surface 61 of the slot 60 in the support bar 10, so that further rotation is no longer possible. In this position the chair leg 3 is directed diagonally forwards, as shown in Fig. 1 and 2. The joints 21, 41 and 52 are designed in the same way.

Figure 7 shows a detail of the joint 22 at the lower end of the right front chair leg 2. The cranked end 24 of the chair leg 2 and the front end of the support rail 10 are each provided with a slot 26 or 27, which are dimensioned so that the two ends can be fitted into one another. The other joints 31, 42, 51 are designed in the same way. These joints can rotate freely, but they can also be provided with a rotation angle limit in a similar way to the joint 32 by shaping the slots and webs of the ends of the chair leg and support rail accordingly.

Alternatively, the angle of rotation can also be limited by a stop pin which is arranged at the end of the stand rail or chair leg and engages in a corresponding groove in the other part, whereby the circular sector over which this groove extends determines the angle of rotation.

Claims (11)

1. Folding chair with
two right ( 2 , 3 ) and two left ( 4 , 5 ) chair legs,
a right ( 6 ) and a left ( 7 ) seat bar, which connect the upper ends of the right and left chair legs, respectively,
a front ( 8 ) and a rear ( 9 ) crossbar which connect the seat bars ( 6 , 7 ) at their ends,
and with a backrest ( 12 ) pivotably attached to the rear end of the seat bars ( 6 , 7 ),
characterized in that
the lower ends of the right ( 2 , 3 ) and left ( 4 , 5 ) chair legs are connected to a right ( 10 ) or a left ( 11 ) support bar, and that the connections of the chair legs ( 2 , 3 , 4 , 5 ) to the associated seat bars ( 6 , 7 ) and the support bars ( 10 , 11 ) are designed as joints ( 21 , 22 , 31 , 32 , 41 , 42 , 51 , 52 ) to form a four-bar linkage. 2. Folding chair according to claim 1, characterized in that the four-bar linkage is a parallelogram. 3. Folding chair according to one of claims 1 or 2, characterized in that the lower ends of the right ( 2 , 3 ) and the left ( 4 , 5 ) chair legs are connected to cross braces ( 8 , 9 ). 4. Folding chair according to one of claims 1 to 3, characterized in that the angle of rotation of the joints ( 21 , 22 , 31 , 32 , 41 , 42 , 51 , 52 ) is limited by a stop. 5. Folding chair according to one of claims 1 to 4, characterized in that the chair legs ( 2 ) each have a cranked end ( 24 , 34 ). 6. Folding chair according to claim 5, characterized in that the angle α between the long part ( 23 , 33 ) of the chair legs and their cranked ends ( 24 , 34 ) is between about 60° and about 120°, preferably 110°. 7. Folding chair according to one of claims 5 or 6, characterized in that the cranked ends ( 24 , 34 ) in the four-bar linkage are diagonally opposite one another. 8. Folding chair according to claim 7, characterized in that the maximum angle of rotation α of the joints ( 21 , 22 , 31 , 32 , 41 , 42 , 51 , 52 ) corresponds to the angle formed by the cranked ends with the long part of the chair legs. 9. Folding chair according to one of claims 1 to 8, characterized in that in the erected state the angle between the long part ( 23 ) of the front chair legs ( 2 , 4 ) and the base strips ( 10 ) is more than 90°. 10. Folding chair according to one of claims 4 to 9, characterized in that in the folded state the front chair legs ( 2 , 4 ) rest on the support bars ( 10 , 11 ) and the seat bars ( 6 , 7 ) rest on the rear chair legs ( 3 , 5 ). 11. Folding chair according to one of claims 1 to 10, characterized in that the seat surface ( 17 ) is formed by a cloth stretched between the front and the rear cross member ( 8 , 9 ).