EP0156814B1 - Articulated seat - Google Patents

Abstract

The articulated seat comprises at least one support (103, 104), a back rest (100) and a seating (102) articulated together. It further comprises a foot rest (131) articulated to the seating (102) along an articulation (N-N') parallel to the seating-back rest (Y-Y') and back rest-support (X-X') articulations and means (133, 134) for hingedly connecting the foot rest (131) to a back rest portion (100) situated beyond the seating-back rest articulation (Y-Y') with respect to the back rest-support articulation (X-X'), so that any modification of the angular position of the back rest (100) with respect to its support (103, 104) results in an angular modification of the foot rest (131) with respect to the seating (102). The arrangement is particularly used in relaxation chairs with multiple positions.

Description

The present invention relates to an articulated seat which allows the user to continuously modify the relative positions of the backrest and the seat, without significant effort and without having to get up from the seat.

In FR-A-2527061 in the name of the present applicant, a seat has been described comprising at least one backrest and one seat articulated together along a movable axis, the backrest being articulated to a support along an axis parallel to the aforementioned axis, this file and this seat being continuously movable relative to each other between a position in which the file is substantially vertical and the seat substantially horizontal and a position in which the file and the seat are substantially horizontal. According to this patent, this seat is characterized in that at least the displacement of the seat is guided opposite its axis of articulation on the back following a curve chosen so that when the back and the seat move between the two aforementioned positions, the center of gravity of the seat user's body deviates little from a horizontal plane and the user is therefore in a situation very close to equilibrium, which allows you to only need to exert a light pressure on the seat or on the backrest to change its position on the seat.

The main advantage of this seat is that it allows its user to modify the relative positions of the backrest and seat by exerting on them efforts so minimal that they are acceptable even for the elderly and people with physical disabilities .

On the other hand, according to FR-A-711 928, there is known an articulated seat comprising at least one support, a back and a seat articulated together, this back and this seat being continuously movable relative to each other between a position in which the backrest is substantially vertical and the seat is substantially horizontal and a position in which the backrest and seat are substantially horizontal. This seat further comprises a footrest articulated on the seat along an articulation parallel to the seat-back and back-support articulations and means for connecting, in an articulated manner, the footrest to a part of the back located beyond of the seat-back joint with respect to the back-support joint, so that any modification of the angular position of the backrest with respect to its support causes an angular modification of the footrest relative to the seat. The connecting means between the footrest and the backrest comprise at least one link articulated at one of its ends to the footrest and connected in an articulated manner by its other end to the backrest. However, the passage between the sitting and lying positions can not be done without user effort.

The object of the invention is to remedy this drawback by creating a seat in which the passage between the sitting and lying positions and vice versa does not require any particular effort for the user, this seat further providing improvements compared to that described. in FR-A-2 527 061 of the applicant.

According to the invention, this seat is characterized in that at least the movement of the seat is guided opposite its axis of articulation relative to the backrest along a curve determined so that when the backrest and the seat move between the two aforementioned positions, the center of gravity of the seat user's body deviates little from a horizontal plane, in that the link is connected to the backrest by means of a slide articulated on the backrest and in that the end of the link opposite the articulation on the footrest comprises a stud moving in a groove provided on the slide.

This arrangement has a very advantageous advantage from an economic point of view since, for example, compared with the embodiment of FIG. 18 of FR-A-2 527 061, it eliminates a guide system consisting of rotary rollers mounted on the footrest and two complex grooves with several successive curves arranged on the large flanges of the seat, and replaces them by a system comprising simple articulations cooperating with elements already existing on the seat.

In the embodiments described in the aforementioned French patent, there is provided, to guide the relative displacements of the backrest and the seat, a system of grooves in which axes or rollers move arranged on the articulations between backrest, support and seat, the grooves having profiles specially established to ensure the slight displacement of the center of gravity of the user.

According to an advantageous version proposed by the present invention, the backrest is, on the other hand, articulated on the support by a fixed axis and, on the other hand, connected to the seat by an intermediate surface on which it is articulated by a axis integral with said surface, the latter itself being articulated at its other end, both on the seat and on one of the ends of a connecting rod whose other end is articulated on the support along a fixed axis located near the fixed axis on which the backrest is articulated.

A first advantage of this embodiment is the flexibility and comfort that the intermediate surface between the backrest and seat gives in the angle changes between them when moving from one position to another, and a second advantage is that the seat guide grooves are straight because they no longer need to have a particular curvature.

According to another embodiment, the means for guiding the seat comprise a connecting rod, one of the ends of which is articulated along a fixed axis on the support, the other end being articulated on an axis integral with said seat. This provision has the advantage of eliminating the friction between axes and grooves, the friction being always less important on the connecting rods.

According to another embodiment, the means for guiding the seat comprise two connecting rods articulated on the same free axis in a fixed groove on the seat, the other end of one of the two connecting rods being articulated along a fixed axis on the support and the other end of the other connecting rod being articulated on the backrest along an axis located on the backrest beyond the backrest-seat joint with respect to the backrest-support joint, this arrangement having the same advantage as the previous one as regards the reduction of friction.

According to another embodiment, the means for guiding the seat include a deformable parallelogram, one of the four sides of which is formed by a part of the seat and one of the articulations of which merges with the back-seat articulation, the articulation opposite to this articulation carrying at least one roller rolling on a fixed ramp secured to the support, the fact of replacing axes moving in grooves by rollers rolling on ramp bringing an additional reduction in friction.

Other features and advantages of the invention will appear in the description below.

• la figure 1 est une vue en perspective d'un fauteuil conforme à l'invention ;
• la figure 2 est une vue latérale partielle du fauteuil ;
• les figures 3, 4 et 5 montrent schématiquement un fauteuil dans trois positions différentes ;
• la figure 6 est une vue latérale partielle d'une variante de réalisation d'un fauteuil ;
• les figures 7, 8, 9 et 10 sont les schémas de quatre autres variantes de réalisation de l'invention.

In the appended drawings, given by way of nonlimiting examples:

• Figure 1 is a perspective view of an armchair according to the invention;
• Figure 2 is a partial side view of the chair;
• Figures 3, 4 and 5 schematically show a chair in three different positions;
• Figure 6 is a partial side view of an alternative embodiment of an armchair;
• Figures 7, 8, 9 and 10 are diagrams of four other alternative embodiments of the invention.

The embodiment shown in Figures 1 to 5 reproduces that illustrated in Figures 1 to 6 of French patent 82 08 778, but improved according to the present invention.

It is a garden armchair made of plastic material which has a back 100, a seat 102 and four legs 103, 104, the legs 103 carrying at their upper part two armrests 103a.

As in the case of FIGS. 1 to 6 of the aforementioned French patent, the backrest 100 is articulated on the rear legs 103 along a fixed horizontal axis X-X 'and on the seat 102 along an axis Y-Y' also horizontal but mobile.

The feet 104 carry rollers which can be mounted on ball bearings or be coated with an anti-friction material and which cooperate with grooves 105 provided in the flanges 106 of the seat 102 to allow a certain displacement of the latter, when the backrest 100 changes from the vertical position to the horizontal position or vice versa. This displacement is such that the center of gravity of the user's body moves a sufficiently small distance in the vertical plane so that the forces necessary to move from one position to the other are acceptable even for an elderly person or disabled.

The modification made to the aforementioned embodiment of the French patent is the presence of a footrest 131 with its control system (see FIGS. 1 and 2).

The rods 4a appearing in FIGS. 2 and 3 of the aforementioned French patent have been deleted here and replaced by a slide 134 which, with two straight rods 133, constitute the control system of the footrest 131.

This comprises two ears 132 which are articulated on the one hand on the seat 102 along the horizontal axis N-N 'and on the other hand on the two links 133 along the horizontal axis P-P'. The other end of the links 133 is articulated on the slide 134 along the horizontal axis M-M ', the slide 134 itself being articulated on the backrest 100 along the horizontal axis Q-Q'. Finally, the slide 134 has, like the rods 4a of Figures 2 and 3 of the main patent, grooves 105b. But in the present case, these are grooves which cooperate with the rollers of the feet 104 to ensure the movement of said slide 134 relative to the seat 102.

When the backrest 100 is in the vertical position (see FIG. 3), the seat 102 is in the low position, the rollers 107 fixed to the feet 104 being in high abutment on the end of the grooves 105. As for the slide 134, it is in the maximum rear position and the links 133 ensure the vertical positioning of the footrest 131 while maintaining the axis PP 'in its extreme position towards the rear of the seat 102.

When the backrest 100 begins to tilt (see FIG. 4), the assembly consisting of the seat 102, the slide 134 and the footrest 131 begins to rotate around the fixed axis XX ′. But, simultaneously, the seat 102 by the combined action of the rollers 107 and the grooves 105, begins a rocking movement around the axis Y-Y ', a movement which causes its front to rise somewhat.

For its part, the slide 134, by the rocking movement of the seat 102 on which it is articulated and by the combined action of the rollers 107 and the grooves 105b, has its own rocking movement around the axis Q-Q ', and since this axis is located, relative to the fixed axis XX' further than the axis Y-Y ', its linear displacement is greater than that of the axis YY' for the same angular displacement. The result of this greater displacement is that it advances the slide 134 relative to the seat 102. Thanks to this forward movement, the links 133 operate on the axis P-P ', which causes the rotation of the footrest 131 which therefore makes movement towards the horizontal position.

In the last part of the movement (see FIG. 5), when the rollers 107 arrive roughly at the bottom stop on the end of the grooves 105, the rotation around the axis XX 'brings up the rear of the seat 102 due to the shape of said grooves 105, which brings the seat to the horizontal. As for the slide 134, it continues its forward movement and the footrest 131 continues its rotational movement to the horizontal position.

It should be noted that the angular displacement of the footrest, if it is linked to that of the backrest, is not identical to it. It is also a function of the distance between the joints NN 'and PP' and of the path difference of the joints QQ 'and Y-Y', which difference is itself a function of the distances of these joints from the fixed axis X-X '.

The farther the joint Q-Q 'is from the joint Y-Y', the longer its path, for the same angular displacement, and the greater the relative movement between the seat 102 and the slide 134. Therefore, for a given distance from N-N 'to P-P', the greater the angular displacement of the footrest.

In the reverse movement, when the backrest 1 rises vertically, the seat 102 lowers slightly while the slide 134, moving back more than the seat, moves the rods 133 and therefore the part of the articulated footrest in P-P ', which results in the rotation of the latter around NN' in an anti-clockwise direction and in its return to the vertical position.

As in the case of the main patent, the different positions of the backrest 100 and of the seat 102 can be blocked by clamping levers 109. But, moreover, these also block the footrest 131 by blocking the slide. 134.

Given that the mounting and the relative positions of the backrest 100 and of the seat 102 are the same as in FIGS. 1 to 7 of the main patent, there remains the essential advantage concerning the small vertical clearance of the center of gravity of the seat user.

But there is added at least one advantage compared to the two embodiments described in the main patent: compared to the first, greater comfort due to the presence of the footrest 131 and this, without considerably increasing the cost price , and compared to the second, a significantly reduced cost price, without reducing reliability.

In FIG. 7, the seat shown diagrammatically comprises a backrest 151, a seat 152 and a support 153 with four legs 154 and 155.

An intermediate bearing surface 156 is provided between the backrest 151 and the seat 152. It is articulated at 157 on the base of the backrest 151 and at 158 on the rear of the seat 152.

The backrest 151 is articulated on the support 153 along a fixed axis 159 and the seat 152 carries two rollers 160, one on each side, which circulate in grooves 161 forming part of the support 153.

Two links 162, one on each side, are articulated, on the one hand on the support 153 along a fixed axis 163 and, on the other hand, on the articulation 158 connecting the intermediate bearing surface 156 and the seat 152 .

The operation of the seat according to the invention is as follows:

The backrest 151, by tilting backwards during its passage from the vertical position to the horizontal position, moves the seat 152 opposite which, thanks to the inclination of the grooves 161, comes to rest first in its front part, then in its rear part, at the level of the backrest when it reaches its horizontal position.

Thanks to the intermediate surface 156 and to the connecting rods 162, the result is greater flexibility and greater comfort for the user when moving from one position to another. On the other hand, the seat guide grooves have become rectilinear.

In FIG. 8, the seat includes a backrest 171, a seat 172 and a four-legged support 173 174, 175.

The backrest 171 is articulated on the support 173 along a fixed axis 176. The seat 172 and the backrest 171 are articulated one on the other at 177.

Two connecting rods 178 are articulated at one of their ends on the feet 174 of the support 173 along a fixed axis 180, the other end of the connecting rods being articulated at 179 on the seat 172.

Compared to the operation of the embodiment of the invention described in Figure 7 attached, the difference comes from the replacement by the two connecting rods 178 of the guide system of the seat with grooves and rollers.

When the backrest 171 switches from the vertical position to the horizontal position, the seat 172 is moved forward and its normalization is effected by the two connecting rods 178, the role of which is therefore the same as that played, for example , by the grooves 161 and the rollers 160 of FIG. 7.

In addition to its greater ease of production, this system has the advantage of having very reduced friction compared to that of axes or rollers guided in grooves.

In FIG. 9, the seat comprises a backrest 191, a seat 192 and a four-legged support 193 194, 195.

The backrest 191 is articulated on the support 193 along a fixed axis 196. The seat 192 and the backrest 191 are articulated one on the other in 197.

A stick 200 continues the file beyond the axis 197 and constitutes one of the sides of a deformable parallelogram whose three other sides are formed by the part 203 of the seat 192 and two rods 201 and 202. The rod 201 is articulated at one of its ends on the seat 192 along an axis 204, while the rod 202 is articulated on the stock 200 along an axis 206, the two rods being moreover articulated one on the another along an axis 205 carrying at least one roller 199 which rolls on a ramp 198 fixed on the support 193.

When the backrest tilts backwards, the stick 200 forming an integral part of the backrest 191 rotates with it around the fixed axis 196, pushing forward the rod 202 and therefore the rotating roller 199 which rolls on the ramp 198.

Thanks to the fact that the parallelogram formed by the butt 200, the rod 202, the rod 201 and the part 203 of the seat is deformable, the cam movement caused by the roller 199 while rolling on the ramp 198, raises the front of the seat 192, which is thus in the normal position when the backrest 191 reaches the position horizontal at the same time as the rear of the seat.

Again, such an arrangement has the advantage of reducing friction compared to a guide system by grooves and rollers.

Of course, the invention is not limited to the examples which have been described and numerous modifications can be made thereto without departing from the scope of the invention.

FIG. 6 shows precisely an alternative embodiment of the seat illustrated in FIGS. 1 to 5. Instead of being articulated by a fixed articulation on the slide 134, each link 133 carries a stud 135 which moves in a groove 136 disposed on the slide 134. Thanks to its weight, the footrest puts the nipples 135 into abutment at the ends of the grooves 136, which allows the slide to transmit its action, the advantage of the grooves being allowing the chair to be folded under less size.

FIG. 10 also shows another embodiment which constitutes a variant of FIG. 8.

We have a seat with a backrest 211, a seat 212 and a support 213 with four legs 214 and 215.

The backrest 211 is articulated on the support 213 along a fixed axis 216 and the seat 212 is articulated at 217 on the backrest 211.

On each side of the seat, a connecting rod system is provided comprising a first connecting rod 218 articulated at one of its ends on the feet 214 of the support 213 along a fixed axis 222, the other end being carried by a joint 220.

The articulation 220, which moves in a light 221 secured to the seat 212, also carries one end of a second connecting rod 219 the other end of which is articulated at 223 on an extension of the backrest 211.

When the backrest 211 is in the vertical position, the articulation 220 carrying one end of the two connecting rods 218 and 219 is located in the rear part of the lumen 221.

When it begins to tilt backwards, the seat 212 and the link 219 are moved forward. But because the link 219 is articulated on the extension of the backrest, it will move forward faster than the seat.

The articulation 220 will therefore move forward inside the lumen 221 until it comes to the end of the travel, in abutment. During the movement, the connecting rod 218 went from an inclined position at the start to a substantially vertical position at the end of the movement, thus playing the same role as the connecting rod 178 in FIG. 8.

The invention can also be applied to any other type of seat, provided that it comprises at least one backrest, a seat and possibly a footrest.

Finally, the movement of the various articulated elements could be motorized by means of a low power motor controlled by the user and the invention can be applied to a bed base.

Claims (5)

1. An articulated chair comprising at least one support (103, 104), a back (100) and a seat (102) which are articulated to one another, the back and the seat being continuously displaceable relatively to each other between a position in which the back is substantially vertical and the seat is substantially horizontal and a position in which the back and the seat are substantially horizontal, a foot rest (131) articulated on the seat (102) about an articulation (N-N') parallel to the seat-back articulation (Y-Y') and the back-support articulation (X-X'), and means (133, 134, 135, 136) for pivotally connecting the foot rest (131) to a part of the back (100) situated beyond the seat-back articulation (Y-Y') relatively to the back-support articulation (X-X') ; in such manner that any modification of the angular positon of the back (100) with respect to its support (103, 104) involves an angular modification of the foot rest (131) with respect to the seat (102), the connecting means between the foot rest (131) and the'back (100) comprising at least one link (133) articulated at one of its ends to the foot rest (131) and pivotally connected by its other end to the back (100), characterised in that at least the displacement of the seat is guided opposite to its articulation axis with respect to the back along a curve so defined that when the back and seat move between the two said poisitions the centre of gravity of the body of the user of the chair does not deviate substantially from a horizontal plane, in that the link (133) is connected to the bacl (100) by means of a guide (134) articulated on the back (100) and in that the end of the link (133) remote from the articulation on the foot rest (131) comprises a stud (135) moving in a groove (136) provided on the guide (134).

2. An articulated chair according to claim 1, characterised in that the back (151) is, on the one hand, articulated on a support (153) about a fixed axis (159) and, on the other hand, connected to the seat (152) by an intermediate surface (156) on which it is articulated by an axis (158) connected to said surface, the latter in turn being articulated at its other end by an axis (158) both to the seat (192) and to one of the ends of a link (162) whose other end is articulated on the support (153) about a fixed axis (163) situated near the fixed axis (159) on which the back (151) is articulated.

3. An articulated chair according to claim 1 or 2, characterised in that the means for guiding the seat (172) comprise a link (178), one of the ends of which is articulated about a fixed axis (180) on the support, the other end being articulated on an axis (179) connected to said seat.

4. An articulated chair according to any one of claims 1 to 3, characterised in that the means for guiding the seat (212) comprise two links (218, 219) articulated on the same axis (220) free in a fixed slot (221) on the seat, the other and of one (218) of the two links being articulated about a fixed axis (222) on the support, and the other end of the other link (219) being articulated on the back (211) about an axis situated on the back beyond the back-seat articulation (217) with respect to the back-support articulation (216).

5. An articulated chair according to any one of claims 1 to 4, characterised in that the means for guiding the seat (192) comprise a deformable parallelogram, one of the four sides of which (200, 201, 202, 203) is formed by a part (203) of the seat (192) and one of the articulations of which coincides with the articulation (205) situated remote from said articulation bearing a roller (199) rolling on a fixed ramp (198) on the support (193).

Images