EP1159888A1 - Height-adjustable support leg - Google Patents

Abstract

The foot for a desk or work table whose height can be adjusted comprises a column (1) mounted on a base (2). A tube (3), which carries a support bracket (4) for a work surface at its upper end, slides in upper (11) and lower (10) guides mounted in the column. The tube can be locked in position by a pivoting lever (12).

Description

The present invention relates to a furniture leg at height adjustable especially intended to equip office furniture with trays forming work plans.

For offices, work tables etc ..., the possibility of a height adjustment provides additional comfort because such adjustment improves the adequacy between the user (s) and their workstation of work by allowing an adaptation either to the size of said users, either to the type of work carried out on the corresponding platforms.

There are many solutions to this problem, simpler ones offering manual adjustment between a few positrons discreet, to the most complicated allowing a continuous adjustment fully automated.

The main purpose of the present invention is to provide a simple and robust adjustment system, than any fitter can be implemented without tools at the location of the installation furniture.

According to another essential objective, the system of the invention allows a continuous adjustment allowing a very fine adjustment to the specifics of the workstation or the morphology of the occupant of that post.

To this end, the furniture leg of the invention, comprising essentially an external barrel in which a tube slides between two positions determining the amplitude of the height adjustment, is characterized in that that the tube is guided in the barrel by means of a share of at least two guide parts and on the other hand a movable locking / unlocking handle between two stable positrons, a lateral guide position in which the tube is slidable in the barrel, and a locking position in any relative tube / barrel positioning, said guide pieces and said lever being arranged on either side of the tube and exerting antagonistic actions for the blocking.

The guide position is actually a loose position in which the lever is no longer in contact with the tube. However, it is configured so to be close enough to said tube, so that during sliding, it constitutes a lateral guide member practically in the same way as the parts on the other side.

According to a preferred configuration, said guide parts are at number of two, arranged directly above each other, one being fixed to the base of the tube and the other being kept fixed in translation near the end top of the barrel.

The lower guide therefore performs rather external guidance, while the upper guide implements internal guidance.

To this end, said guide parts having an external surface of which at least a portion is provided to fit the inner wall of the barrel, at least a portion of their internal surface being designed to match the outer wall of the tube.

Preferably, at least one of the lateral end surfaces of the pieces of speed guide parallel to the sliding axis, intended to come into contact respectively with the internal wall of the barrel and the external wall of the tube, and oriented substantially perpendicular to the direction of action of the forces of locking, have an angle of inclination relative to the vertical allowing the pivoting of said parts upwards by an equivalent angle when they are in contact with said walls.

This structural feature makes it possible to reduce, due to this pivoting, the distance between the external wall of the tube and the internal wall of the barrel, walls which are develop vertically. When locking, tightening results in bending of the guide parts to bring them closer to the horizontal, increasing the distance above, and making friction blocking more effective.

According to one possibility, validated by numerous tests, this angle is understood between 1 ° and 3 °, and is preferably centered in this interval.

More precisely, the guide parts have a portion in the form of fork inside the branches of which the sliding tube fits, the outside said branches fitting into the barrel.

The internal surface of the branches actually follows the external shape of a portion of the tube, while their outer surface matches part of the wall internal of the barrel. Depending on the case, it can be more or less complex, especially in its lateral zones housing the guide parts, which then have a shape adapted to this complexity, as we will see more in detail below.

The interior of the fork legs is provided in the vicinity of where they meet with an orifice which can accommodate a flexible pad.

This accommodation is not systematically used: in the context of the invention, only the guide piece located near the upper end of the barrel has a cylindrical pad made of flexible absorbent material. It's here only one of the two guide pieces which in fact performs internal guidance.

This synthetic material shoe further improves the necessary friction effect blocking, as well as guidance when the tube is not blocked.

This same upper guide piece is supported by at least one support element fixed to the internal wall of the barrel, and it is held in part upper by a cover forming the upper end of said barrel, and comprising an opening for the passage of the sliding tube.

Although this guide piece is not directly attached to the barrel, it is therefore maintained in vertical translation by the above-mentioned elements, and it is immobilized in a horizontal direction between the tube and the barrel.

Preferably, the guide piece fixed to the base of the foot is clipped onto it, each branch of the fork comprising for this purpose a housing provided for receive a relief protruding from the outer wall of the tube, the two branches of the fork deforming during the passage of their end over said reliefs, until the latter arrive in front of said accommodation and stay there, the branches then resiliently returning to their initial position in contact with the tube.

Although this is only one method of attachment among others, it is a quick way to proceed, which does not require any tools.

More preferably, for obvious economic reasons, said guide parts are identical, whether fixed at the bottom or held in the upper part, between the tube and the barrel.

In the system of the invention, opposite the guide parts, and exercising an antagonistic action to effect blocking, is the joystick height adjustment control.

This includes a manipulation lever and a fork cooperating with a lateral end of the tube, said handle being able to pivot relative to said between two positions, a first position in which the fork guides the tube in its sliding movement relative to the barrel and a second locking position in tight contact against the tube.

For this purpose, the internal wall of the fork has a rounded surface such that in any pivoting position of the lever, it has in a plane perpendicular to the sliding axis a curve adjusting substantially to the external profile of the tube, and the distance from which varies in depending on the pivoting position.

In fact, the internal surface of the fork acts as a cam tightening / loosening, exerting when in contact with the barrel a radial action in opposite direction of the reaction exerted by the aforementioned guide parts. The forks of the latter are oriented in opposite direction to the fork of the lever, the assembly constituting clamping jaws frictionally locking the tube in the barrel at a given position.

According to one possibility, the lever pivots in an opening of the barrel allowing the passage of the handling lever, this being arranged outside the barrel while the fork is inside, the pivot axis being constituted by rounded edges disposed on said fork near the internal surface of lever / fork connection, on both sides of the lever, said edges rolling on the internal wall of the barrel on either side of the opening.

This lever is therefore not connected to the barrel by a mechanical connection permanent, but on the contrary is removable and installable - in the absence of tube - without any tools, immediately.

According to one configuration, the handling lever and the fork are arranged substantially perpendicular to each other, the fork being in close contact with the barrel when the lever is parallel to the wall of said barrel, and in the guide position without contact when the lever is perpendicular to the barrel.

This structure is advantageous because it allows the lever to be pressed against the was in the usual operating position, or even hiding it when it is placed in an axial channel or groove made in the external wall of said barrel.

According to the invention, the internal wall of this barrel has at least one stop upper for the guide piece fixed to the base of the tube.

This stop marks the upper limit of elevation of the system, the limit lower being of course produced by the contacting of the barrel of the elements supported by the tube (for example a sole supporting a tray).

Preferably, each upper stop is associated with an element of support of the guide piece located near the upper end of the barrel to form a single piece attached to the inner wall of the barrel.

It can be one or more plates fixed axially to the internal wall of the barrel, and which fulfill another function which does not participate in the present invention, and is therefore not explained in detail.

To correctly adjust several feet supporting the same structure, the tube sliding in the barrel is provided with graduations allowing measure its position relative to the barrel. It is therefore possible to standardize the adjustment from one tube to another, uniformity necessary to obtain horizontality correct for example for the desk top.

• la figure 1 est une vue en élévation de la face d'un pied de mobilier selon l'invention, en position bloquée ;
• la figure 2 est quasi-identique à la précédente, mais en position débloquée autorisant le coulissement relatif du tube dans le fût ;
• la figure 3 représente une vue en perspective d'un fût équipé d'un système de l'invention ;
• la figure 4 montre une section transversale d'un tel fût ;
• la figure 5 représente une vue en perspective d'une manette de commande selon l'invention ;
• la figure 6 en est une vue de face ;
• la figure 7 montre une coupe de ladite manette selon les flèches VII-VII de la figure précédente ;
• la figure 8 illustre une pièce de guidage possible, en vue perspective ;
• la figure 9 en est une vue de face ; et,
• la figure 10 montre ladite pièce en vue de côté.

The invention will now be described in more detail, with reference to the appended figures, for which:

• Figure 1 is an elevational view of the face of a furniture leg according to the invention, in the locked position;
• Figure 2 is almost identical to the previous one, but in the unlocked position allowing the relative sliding of the tube in the barrel;
• FIG. 3 represents a perspective view of a barrel equipped with a system of the invention;
• Figure 4 shows a cross section of such a barrel;
• FIG. 5 represents a perspective view of a control handle according to the invention;
• Figure 6 is a front view;
• Figure 7 shows a section of said lever according to arrows VII-VII of the previous figure;
• FIG. 8 illustrates a possible guide part, in perspective view;
• Figure 9 is a front view; and,
• Figure 10 shows said part in side view.

Referring to Figure 1, the furniture leg shown comprises essentially a barrel (1) surmounting a base (2), and a tube (3) sliding in the barrel (1) and supporting a sole (4) connecting to an upper element, by example a tray (not shown). The barrel is shown in broken lines, with the exception of a wall (5) which plays an essential part in the the invention. This representation also symbolizes the transparency that is artificially conferred, allowing the visualization of the components of the invention.

The base (2) is mounted on adjustment cylinders (6), allowing in particular adaptation to uneven soils. The upper sole (4) is mounted on an upper portion (7) of barrel, the base of which is closed by a cover (8), which comes into contact with the cover (9) obstructing the upper part of the barrel (1), marking the position in which the tube (3) is in bottom stop.

Without going into the construction details of each component, which will be studied more thoroughly in the following, it should be noted that the tube (3) cooperates, inside barrel (1), with two guide pieces (10,11) and a handle (12), which is shown in the locked position. In the representation of Figure 1, the foot is therefore blocked in the configuration as shown.

The guide piece (10) is fixed in the vicinity of the lower end of the tube (3), using two screws (13) located symmetrically with respect to said tube (3) and therefore only the head of one appears. This screw (13) is actually screwed directly in the tube and allows clipping of the lower guide piece (10) by inserting the screw head (13) into the holes (14), as will be explained in more detail below, with reference to the shape of this part (10).

The guide piece (11) located near the upper end of the barrel (1) is not fixed to the tube (3), or even directly to the barrel (1). She is actually held between the cover (9) and at least one support element (15) fixed to the wall internal of the barrel (1) in this case by two bolts (16, 16 '). This support (15), as well as the bolts (16, 16 ') and the slots (17, 17') in which the latter are inserted, performs other functions unrelated to the invention, and as such not described here.

The locking / unlocking handle (12) comprises a manipulation lever (18), as well as a fork (19) whose branches grip the tube (3) and whose internal surface achieves either blocking by clamping the tube (3) between the pieces of guide (10, 11) and the lever (12), i.e. the guide when there is no contact between the fork (19) and said tube (3). This is the position that is shown in Figure 2: the lever is now perpendicular to the sliding axis after pivoting the joystick about 90 ° counterclockwise.

In this case, it is possible to slide the tube (3) in the barrel (1) between lateral guides made up of two guide parts (10, 11) on one side, and of the handle (12) in its new position on the other side. A graduation (20) printed on the tube (3) allows precise measurement of the height adjustment operated on the foot.

With reference to figs 3 and 4, the barrel (1) consists of a cut sheet and folded, even stamped, which creates an internal volume of particular shape, the envelope is produced by said thin sheet. This sheet closes on itself, enclosing said volume, at the level of the wall (5) set back relative to the actual end, so that a side channel (21) is created which can be closed by a cover (22) clipped at this level (see Figure 4).

In the wall (5), opening into the channel (21), an opening (23) allows the passage of the lever (12) appearing in FIGS. 5 to 7. Said lever (12) is not attached to the barrel (1). It is inserted from the inside, so that the lever (18) passes outside said wall (5) via the opening (23), which is however too small to allow passage of the fork (19). In short, the part handle (18) of the handle (12) is accessible from outside the barrel (1) then that the "active" part, that is to say the fork (19) is retained inside the barrel (1) between the wall (5) and the tube (3).

• la surface (24), rejoignant les deux branches (25, 26) de la fourche (19), présente un gauchissement dans l'espace (voir en particulier la figure 7) tel qu'il autorise d'une part la rotation et d'autre part le blocage/déblocage de la manette (12). La rotation ne rencontre pas d'obstacle du fait de l'existence de la courbe (27), visible dans le plan de la figure 7. À tout moment, dans un plan perpendiculaire à ce dernier et à l'axe du coulissement, la surface (24) offre de plus une courbe (28), qui permet d'épouser le contour latéral du tube (3), que cela soit en contact serré lors du blocage (en position des figures 1, 6 et 7) ou à distance lors de la phase de guidage (représentée en figure 2). Dans ce dernier cas, seule la courbe (28') apparaissant en figure 6 est concernée.
• Les portions arrondies (29, 29') localisées de part et d'autre du levier (18), permettent d'assurer le pivotement de la manette (12) par appui sur les surfaces localisées de part et d'autre de l'orifice (23) de la paroi (5) (voir figure 3). Il n'y a pas d'axe fixe, la rotation résultant du roulement de la manette (12) sur ladite paroi (5), via ces portions arrondies (29, 29').

Two areas are essential in the fork (19):

• the surface (24), joining the two branches (25, 26) of the fork (19), presents a warping in space (see in particular FIG. 7) such that it allows on the one hand the rotation and d 'other hand blocking / unblocking the handle (12). The rotation does not encounter any obstacle due to the existence of the curve (27), visible in the plane of FIG. 7. At any time, in a plane perpendicular to the latter and to the axis of the sliding, the surface (24) moreover offers a curve (28), which makes it possible to follow the lateral contour of the tube (3), whether this is in close contact during blocking (in the position of FIGS. 1, 6 and 7) or at a distance during the guidance phase (shown in Figure 2). In the latter case, only the curve (28 ') appearing in FIG. 6 is concerned.
• The rounded portions (29, 29 ') located on either side of the lever (18), allow the pivoting of the lever (12) by pressing on the surfaces located on either side of the orifice (23) of the wall (5) (see Figure 3). There is no fixed axis, the rotation resulting from the rolling of the lever (12) on said wall (5), via these rounded portions (29, 29 ').

In the position shown in Figures 5 to 7, the handle (12) is generally vertical, that is to say in the clamping position. In this case, the distance between the rounded portions (29, 29 ') and the curve (28) located approximately in the same horizontal plane is maximum, where the contact with the tube (3) and the blocking.

However, the distance between said portions (29, 29 ') and the curve (28') is minimal, which explains the absence of contact, when the handle is arranged in the unlocked position, after rotation of 90 ° counterclockwise.

The fork (19) of the lever (12) exerts, in the locked position, an action on the lateral end of the tube (3), the external shape of which is intended to fit between the branches (25, 26), in contact with at least one curve (28) of the left surface (24).

At the other lateral end, the guides (10, 11) have an internal surface (30), designed to accommodate said end in order to exert a reaction thereon antagonist during blocking. These guide pieces (10, 11) have also a general shape (see figures 8 to 10) in the form of a fork with two arms (31, 32) and an axial portion (33) which adjusts in the lateral end cylindrical in shape of the barrel (1), as it appears for example in Figures 3 and 4.

This axial portion (33) is split at (34) so as to increase the flexibility branches (31, 32), in particular for fixing purposes (see below). The branches (31, 32) and said portion (33) have upper edges and lower (35, 36) continuous which adjust in the volume delimited by the internal wall of the rounded lateral portion of the barrel (1).

A cylindrical housing (37) equips the internal wall (30) of the pieces of guide (10, 11), for housing a cylindrical shoe of flexible plastic material improving friction blocking when tightening (not shown). Each branch (31, 32) further comprises an elongated orifice (14, 14 ') which can accommodate a protrusion (for example a screw head (13) as in Figures 1 and 2) fixed to the tube (3). The fixing is then carried out as follows: the screw heads (13) being fixed to the tube (3), it suffices to engage the guide piece to be fixed from the lateral end of the tube (3) until said heads (13), bearing on the inclined planes (40, 41), separate the branches (31, 32) from one another. The heads (13) are then housed in the holes (14, 14 ') when continuing inserting the guide piece, making the clipping.

Figure 8 shows in transparency the shape of the tube (3) as inserted in the guide parts (10, 11). As previously mentioned, only the part (10) is fixed to said tube (3). Referring to Figure 10, all walls or virtual vertical walls oriented transversely to the room guidance are not parallel: an angle α, preferably chosen at around 2 ° was provided between the end walls (42) and the wall (30) at in the vicinity of the orifice (37) on the one hand, and the other vertical walls or sides and of the same global orientation, on the other hand. The surfaces or walls concerned are those which have a role in the exercise of actions at the time of blocking: this are of which those which are generally perpendicular to the resultant of the forces exercised during blocking.

When the surface (42), actually composed of the end surfaces of the edges (35, 36) to which this angle α is applied, comes into contact with the wall internal of the barrel (1), the entire guide piece is pivoted from α to the top, which decreases the distance between the outer side end wall of the tube (3) inserted in the fork and the side end wall of the barrel (1).

When the blocking is implemented, the force exerted by the lever (12) is passed through the tube (3) to the guide parts (10, 11), so that said pivoting of α upwards is countered, and said parts (10, 11) tend to return to a more horizontal position, increasing the aforementioned tube distance (3) / barrel (1) and accentuating their mutual actions: the blockage is then total.

The above invention has only been described by means of examples which are not not limiting. Rather, it encompasses variations in shape and design which are within the reach of ordinary skill in the art.

Claims (18)

Height-adjustable furniture leg, essentially comprising an external barrel in which slides a tube between two positions fixing the amplitude of the height adjustment, characterized in that the tube is guided in the barrel by means of at least one part two guide pieces and on the other hand a movable blocking / unblocking handle between two stable positions, a lateral guide position in which the tube is slidable in the barrel, and a blocking position in any relative position tube / barrel, said guide parts and said handle being arranged on either side of the tube and exerting antagonistic actions for blocking. Height-adjustable furniture leg according to the preceding claim, characterized in that said guide pieces are two in number, arranged vertically to one another, one being fixed to the base of the tube and the the other being kept fixed in translation in the vicinity of the upper end of the barrel. Height-adjustable furniture leg according to the preceding claim, characterized in that said guide pieces having an external surface of which at least a portion is provided to match the internal wall of the barrel, at least a portion of their internal surface being designed to marry the outer wall of the tube. Height-adjustable furniture leg according to the preceding claim, characterized in that at least one of the surfaces of the guide pieces having a shape parallel to the sliding axis intended to come into contact respectively with the internal wall of the barrel and the external wall of the tube, and oriented substantially perpendicular to the main direction of the locking efforts, have an angle of inclination relative to the vertical allowing their pivoting upwards by an equivalent angle when they are in contact with said walls. Height-adjustable furniture leg according to the preceding claim, characterized in that the angle is between 1 ° and 3 °. Height-adjustable furniture leg according to one of claims 3 to 5, characterized in that the guide pieces have a fork-shaped portion inside the branches of which the sliding tube fits, the outside of said branches fitting into the barrel. Height-adjustable furniture leg according to the preceding claim, characterized in that the interior of the legs of the fork is provided in the vicinity of where they meet with an orifice which can accommodate a flexible pad. Height-adjustable furniture leg according to the preceding claim, characterized in that the guide piece located in the vicinity of the upper end of the barrel comprises a pad of cylindrical appearance made of flexible absorbent material. Height-adjustable furniture leg according to one of Claims 2 to 7, characterized in that the guide piece located near the upper end of the barrel is supported by at least one support element fixed to the internal wall of the barrel and is held in the upper part by a cover closing the upper end of said barrel, and comprising an opening for the passage of the sliding tube. Height-adjustable furniture leg according to any one of Claims 6 to 9, characterized in that the guide piece fixed to the base of the leg is clipped to it, each branch of the fork comprising a housing provided for receiving a relief projecting from the outer wall of the tube, the two branches of the fork deforming during the passage of their end over said reliefs, until the latter arrive in front of said housings and are housed there, the branches resiliently returning to their initial position at tube contact. Height-adjustable furniture leg according to any one of the preceding claims, characterized in that said guide pieces are identical. Height-adjustable furniture leg according to any one of the preceding claims, characterized in that the handle comprises a manipulation lever and a fork cooperating with a lateral end of the tube, said handle being able to pivot relative to said barrel between two positions, a first position in which the fork guides the tube in its sliding movement relative to the barrel and a second locking position in tight contact against the tube. Height-adjustable furniture leg according to the preceding claim, characterized in that the internal wall of the fork has a rounded surface such that in any pivoting position of the lever, it has in a plane perpendicular to the axis sliding a curve substantially adjusting to the external profile of the tube, and the distance therefrom varies according to the pivoting position. Height-adjustable furniture leg according to the preceding claim, characterized in that the lever pivots in an opening of the barrel allowing the manipulation lever to pass, the latter being arranged outside the barrel while the fork is at inside, the pivot axis being constituted by rounded edges arranged on said fork close to the internal lever / fork connection surface, on either side of the lever, said edges rolling on the internal wall of the barrel on both sides and other than the opening. Height-adjustable furniture leg according to the preceding claim, characterized in that the handling lever and the fork are arranged substantially perpendicular to each other, the fork being in close contact with the barrel when the lever is parallel to the wall of said barrel, and in the contactless guide position when the lever is perpendicular to the barrel. Height-adjustable furniture leg according to any one of Claims 2 to 15, characterized in that the internal wall of the barrel has at least one upper stop for the guide piece fixed to the base of the tube. Height-adjustable furniture leg according to claims 9 and 16, characterized in that each upper stop is associated with a support element for the guide piece located near the upper end of the barrel to form a single piece fixed to the inside wall of the barrel. Height-adjustable furniture leg according to any one of the preceding claims, characterized in that the tube sliding in the barrel is provided with graduations making it possible to measure its position relative to the barrel.

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