EP0364309A1 - One-shell extruded plastic armchair stackable in a compact manner - Google Patents

Abstract

The armchair comprises various elements consisting of a seat (1) with subjacent stiffening projections, a back (2), four legs (4, 5) and arm rests (3), elements which have substantially horizontal parts and substantially vertical parts, the latter being inclined forming, between their line of greatest inclination and the vertical, a so-called stacking angle (a). <??>According to the invention, the stacking angle (a) is between 8 and 15 DEG in order to reduce the stacking pitch, the connection of the legs with the seat, the arm rests and the back being achieved by reinforced recess and stiffening means inserted in this restricted pitch. <??>Advantageously, this angle (a) is substantially equal to 10 DEG 30' for a wall thickness of approximately 5 mm. <IMAGE>

Description

The present invention relates to a stackable monocoque armchair made of injected plastic, which armchair comprises a seat, a backrest and two armrests integral with four feet.

Such known armchairs have so-called vertical "facets" which correspond to the feet, the backrest, the armrests, the edges and ribs of the seat, etc. and so-called horizontal "facets" which correspond to the seat and other elements which are substantially parallel to it. For such armchairs to be stackable, it is in particular necessary for the lines of greatest slope of the so-called vertical facets to form a particular nesting angle with respect to the vertical; this angle determines as a function of the thickness of these so-called vertical facets and when the so-called vertical facets of the stacked armchairs are in contact with each other, the stacking pitch; of course, the height of the seat with its underlying projections must be less than said pitch, otherwise it determines the latter by abutment.

Very many models of this known armchair exist, probably almost two hundred, and can be classified into several types according to the orientation of the feet.

A first type comprises V-shaped feet open rearward for the rear feet and forward for the front feet.

A second type has V-shaped front legs open towards the rear, while V-shaped posterior legs are open at the sides.

According to a variant, the rear legs are profiled in angles and open on the sides as well as towards the rear.

A third type comprises profiled feet in angles open on the sides and forward for the front feet and rearward for the rear feet.

These armchairs made of molded plastic must meet many imperatives: aesthetics, stability and resistance, comfort, ability to safely support heavy people or unsolicited stresses such as pressing on one or two feet with a rocking movement, possibility of stacking them for transport and storage, easy to dislodge by avoiding jamming, minimum cost of storage and transport, competitive cost price ...

To reconcile all these imperatives, rules of use practiced by all manufacturers have appeared. Thus, the minimum thickness of the feet is of the order of 6 mm and the angle of said feet relative to the vertical is between 5 and 8 degrees without ever exceeding this maximum value.

With such rules, it is possible to constitute a stack of 30 armchairs with a pitch of approximately 60 mm; this pile enclosed in a cover measures a height of 2.30 m compatible with the free height of the means of transport used.

The object of the present invention is to increase the storage and transport capacity in order to reduce the cost of these services. The problem to be solved to achieve this goal is to reduce the stacking pitch.

Once the problem is posed, the invention seems obvious. It suffices to slightly reduce the thickness and increase the stacking angle formed by the vertical line with the greatest slope of the so-called vertical facets mentioned above, an angle which use limits to 8 degrees.

In this case, the directive C-IV 94-i relating to the examination carried out at the European patent office indicates that the inventive activity must be assessed at the level of the formulation of the idea or a problem to solve.

Under these conditions, the characteristic of the invention according to which the stacking angle is between 8 and 15 degrees in order to reduce the stacking pitch, exhibits the inventive activity required, since this must be appreciated. according to the aforementioned directive, not at the level of the characteristic itself which seems obvious, but at the level of the problem to be solved which does not never seems to have been asked.

This characteristic must of course be combined with another characteristic of the invention also appearing obvious, according to which the connection of the feet with the seat, the armrests and the backrest must be carried out by reinforced means of embedding and stiffening s' inserting in this no limited stacking. This other characteristic implies the inventive step required, not in itself but at the level of the problem to be solved, since by reducing the stacking pitch, the height of the underlying elements of the seat intended for stiffening is reduced. the connection of the latter with the feet and that it is then necessary to reinforce the embedments.

To obtain this reinforcement, various and combined means can be used.

First of all, it is a question of increasing the extent of the attachments of the elements which end at the feet.

For this purpose, the third type of seat is selected and the seat which is shaped like a bowl is projecting:
- towards the bottom, an anterior rim and two lateral rims, as well as ribs which are parallel to them,
- upwards, a rounded part of connection with the backrest and, downwards, a rear rib which is parallel to it, as well as upwards the front rising parts of the armrests, all these edges, ribs, rounded part of rear connection and rising parts of armrests integral with the wings of the angles forming the feet.

For the same purpose, the width of the wings of the feet at the level of the apparent upper surface of the seat, that is to say at the root, is included:
- between 85 and 115 mm for the transverse wings and 75 and 105 mm for the anteroposterior wings of the front feet,
- between 60 and 90 mm for the transverse wings and 75 and 105 mm for the anteroposterior wings of the hind feet.

According to a particularly advantageous embodiment, the width of the transverse wings of the feet anterior measures approximately 95 mm and that of the anteroposterior wings approximately 85 mm, while the width of the transverse wings of the hind feet measures approximately 70 mm and that of the anteroposterior wings approximately 85 mm.

Each rising armrest part is profiled in an angle whose transverse wing extends the marginal part of that of the corresponding front leg and whose anteroposterior wing prolongs a recessed part returning from the corresponding lateral edge of the seat.

The bowl-shaped seat has in the median transverse direction an arrow (F) substantially equal to 26 mm for a span (p) substantially equal to 430 mm and a thickness of between 3 and 4 mm.

The ribs have a height (h) substantially equal to 23 mm and are spaced from the edges by a distance of between 80 and 50 mm.

This particular conformation makes it possible to obtain the desired reinforcement.

However, it is permissible to think that the reinforcement thus obtained will not prevent the chair from deforming a little, but that this chair will, despite this, be sufficiently resistant to oppose the various stresses to which it is usually subjected.

The inventive step then also resides in the idea that the resulting flexibility of the chair should be perfectly accepted by the user, contrary to the received idea that the user imperatively seeks rigidity and non-formability. The complementary idea which justifies the inventive step is therefore that the flexibility and deformability of the seat are properties which should appeal to the user provided that safety is ensured (no rupture or spillage).

As soon as this idea is posed, the means to be implemented are obvious: increasing the angle of the feet and accepting just enough embedding; inventive step is therefore not at the level of these means, but according to the aforementioned directive in terms of the formulation of the idea set out above.

Note that these two apparently different inventive ideas: reducing the stacking pitch and increasing the flexibility of the chair are combined and unitary in terms of the means used.

Various other characteristics and advantages of the invention will also emerge from the detailed description which follows.

An embodiment of the object of the invention is shown, by way of nonlimiting example, in the accompanying drawing.

• - la figure 1 est une perspective illustrant un fauteuil conforme à l'invention,
• - la figure 2 est une élévation vue de face du fauteuil,
• - la figure 3 est une vue en plan de dessus de ce fauteuil.

On this drawing :

• FIG. 1 is a perspective illustrating a chair according to the invention,
• FIG. 2 is a front view elevation of the chair,
• - Figure 3 is a top plan view of this chair.

As the drawing shows, the armchair is monocoque and made of injected plastic. It has a seat 1, a backrest 2, armrests 3, front legs 4 and rear legs 5.

The seat 1 is shaped like a concavity bowl directed upwards (FIG. 2) and having an arrow f for a median transverse bearing p (FIGS. 2 and 3). This seat is connected to the backrest 2 by a rounded connection part 6 and has a downward projection.
a front edge 7 and a rib 8 substantially parallel to one another,
- On each side, a side edge 9 and a rib 10 substantially parallel to each other.
- a rear rib 11 substantially parallel to the rounded connection part 6.

The front legs 4 are angles open at the sides and towards the front; in other words, their transverse wings 12 extend in extension from one another towards the exterior and are connected by the anterior rib 8, these transverse wings 12 forming one body with the seat 1, as well as with the lateral edges 9 and the ribs 10 which are substantially perpendicular to them; their anteroposterior wings 13 extend substantially as an extension of the lateral ribs 10 towards the front and are integral with the seat 1, as well as with the front edge 7 and the rib 8.

The rear legs 5 are angles open at the sides and towards the rear; in other words, their transverse wings 14 extend in extension from one another towards the outside and are connected by the rear rib 11, these transverse wings 13 forming one body with the seat 1 as well as with the lateral edges 9 and the ribs 10 which are substantially perpendicular thereto; their anteroposterior wings 15 extend in extension of those 13 of the front legs 4 towards the rear, are connected by the lateral ribs 10 and form a body with the seat 1, the rounded connection part 6 and the posterior rib 11.

These feet 4 and 5 are semi-pyramidal in the sense that their base section is smaller than their head section (Figure 3).

According to the invention, so that the stacking pitch (that is to say the distance from the top of the seat 1 of a seat above that of the neighboring seat in the stack) is reduced, l 'angle "a" of stacking which is that which forms the line of greatest slope of the so-called vertical facets with the vertical is between 8 and 15 °.

This angle "a" is marked in Figure 2 for a front leg 4; in this case, this is the angle formed by the anteroposterior wing 13 with the vertical and which is found for the transverse wing 14 of said foot.

Advantageously, the angle "a" is substantially equal to 10 ° 30 ′.

Still according to the invention, the feet more sloping than until now, are more extended at the head so that the distances extreme attachment points (underlying projecting elements 7 to 11 of the seat 1 and the rounded overlying connection part 6) are larger and thus reinforce the embedding, while the height of said elements 7 to It is reduced in correspondence with the reduction in the stacking pitch.

Thus, at the level of the apparent upper surface of the seat 1 (FIG. 3):
- The width lA of the transverse wings 12 of the front legs 4 is between 85 and 115 mm; advantageously, it measures substantially 95 mmm,
- The width LA of the anteroposterior wings 13 of the front legs 4 is between 75 and 105 mm; advantageously, it measures substantially 85 mm,
- The width lp of the transverse wings 14 of the rear legs 15 is between 60 and 90 mm; advantageously, it measures substantially 70 mm,
- The width LP of the anteroposterior wings 15 of the hind feet 15 is between 75 and 105 mm; advantageously, it measures substantially 85 mm.

At the rear, the embedding of the rear legs 5 is obtained over a greater extent by the rounded connection part 6.

At the front, the embedding of the front legs 4 is obtained more efficiently by the rising part of the armrests 3 which is profiled in angle (FIG. 1). The transverse wing of this part extends at its base the transverse wing 12 of the corresponding front leg 4, while the anteroposterior wing 17 of said part extends a step 18 of the corresponding side edge 9, a step which is hollowed inwards .

Of course, each armrest 3 forms an flying buttress connecting the front leg 4 to the backrest 2.

According to the invention, the concavity of the seat 1 is accentuated, so that said seat behaves like a shell opposing the flattening of the front feet forward and feet back to back when a person sits down. Thus, the arrow "f" in the median transverse direction is substantially equal to 26 mm for a span "p" substantially equal to 430 mm and a thickness of between 3 and 4 mm.

Furthermore, the ribs 8, 10 and 11 have a height "h" substantially equal to 23 mm and are spaced from the edges 7, 9 by a distance "d" between 80 and 50 mmm.

Claims (7)

1.- Monocoque injected plastic armchair, stackable at low pitch and comprising various elements consisting of a seat (1) with underlying stiffening projections (7 to 11), a backrest (2), four feet (4, 5 ) and armrests (3), elements which have substantially horizontal parts and substantially vertical parts, the latter being inclined forming between their line of greatest slope and the vertical, a so-called stacking angle (a),
characterized in that the stacking angle (a) is between 8 and 15 ° to reduce the stacking pitch, the connection of the feet with the seat, the armrests and the backrest being carried out by means reinforced with embedding and stiffening fitting into this limited step. 2.- armchair according to claim 1, characterized in that the stacking angle (a) is substantially equal to 10 ° 30 ′ for a wall thickness of approximately 5 mm. 3.- Armchair according to claim 1 or 2, the feet of which are shaped as angles open on the sides as well as forwards for the front feet (4) and rearwards for the rear feet (5), the seat (1) which is shaped like a bowl projecting:
- downwards, an anterior rim (7) and two lateral rims (9), as well as ribs (8, 10) which are parallel to them,
- upwards, a rounded connection part (6) with the backrest (2) and, downwards, a rear rib (11) which is parallel to it, as well as upwards the front rising parts (16, 17) armrests (3), all these edges, ribs, rounded posterior connection part and rising armrest parts which are integral with the wings of the angles forming the feet,
characterized in that, in order to increase the stiffness of the connection of the feet with the seat while the height of the underlying projecting elements thereof is reduced, the width of the feet wings at the level of the apparent upper surface of the seat is included:
- between 85 and 115 mm for the transverse wings (12) and 75 and 105 mm for the anteroposterior wings (13) of the front legs (4),
- between 60 and 90 mm for the transverse wings (14) and 75 and 105 mm for the anteroposterior wings (15) of the hind feet (5). 4.- armchair according to claim 3, characterized in that the width (lA) of the transverse wings (12) of the front legs (4) measures substantially 95 mm and that (LA) of the anteroposterior wings (13) substantially 85 mm, while that the width (lP) of the transverse wings (14) of the hind feet (5) measures substantially 70 mm and that (LP) of the anteroposterior wings (15) substantially 85 mm. 5.- armchair according to claim 3 or 4, characterized in that each rising armrest part is profiled at an angle, the transverse wing (16) of which extends the marginal part of that (12) of the corresponding front leg (4) and the anteroposterior wing (17) of which extends a re-entrant recessed portion (18) of the corresponding lateral edge (9) of the seat (1). 6.- armchair according to claim 1 or 2, characterized in that the seat (1) in the form of a bowl has in the median transverse direction an arrow (f) substantially equal to 26 mm for a span (p) substantially equal to 430 mm and a thickness between 3 and 4 mm. 7.- armchair according to claim 6, characterized in that the ribs (8, 10) have a height (h) substantially equal to 23 mm and are spaced from the edges (7, 9) by a distance between 80 and 50 mm.

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