FR2754439A1 - Height adjustable leg for tables, bureaux etc. - Google Patents

Abstract

The leg has a pair of telescopic tubes (4,5) with a pair of tubular pieces (10,11) between them. The inner piece (11) is fixed to the end of the larger tube (4) and the outer piece (10) is fixed to the end of the smaller tube (5). A mobile ring (12), to lock or unlock the pieces, is joined to the inner piece. The pieces move on each other by grooves (13,14) and can be locked in position. Teeth (22), inside the inner piece, engage in strips of notches (20) on the outer tube when the ring is tightened.

Description

ADJUSTABLE BASE FOR TABLES, OFFICES, ETC ...

 The present invention relates to an adjustable base for tables, desks and furniture of this kind.

 The adjustment of the table or desk base is necessary to adapt the height of the tray either to its destination or to the morphology of the user.

 It is known practice to use screw-nut adjustment systems, but this system is not suitable for all types of legs and in particular for inclined legs with cantilever supports.

 In addition, it is necessary to use material such as keys, to lock the screw-nut system in order to avoid misadjustments due for example to vibrations.

 The present invention proposes to remedy these various drawbacks. It offers an adjustable base consisting of telescopic tubes, which comprises, interposed between said tubes, a connection system comprising a pair of tubular parts associated respectively with said tubes, which provide guidance in translation while being immobilized in rotation, which parts include means making it possible to block their translational movements, which means are implemented by means of a device in the form of a movable ring secured to one of the parts, which makes it possible to lock or unlock said parts one with respect to the 'other.

 Still according to the invention, the connection system comprises: - a part called an internal part, fixed at the end and inside the large diameter tube constituting a part of the base; - a part called an external part, fixed to the outside of the end of the small diameter tube constituting the other part of the base.

the locking ring being associated with the internal part, mounted and guided on an extension of this internal part, which projects outside of said large diameter tube.

 According to a preferred arrangement of the invention, the external part comprises a notch which extends over at least one strip delimited by a pair of generators, which notch cooperates with at least one comb shaped on the internal part, the teeth of which are arranged on a flexible tongue, which tongue is applied in the active position to lock the two parts by means of the locking ring.

 According to another arrangement of the invention, the locking ring comprises a threaded part cooperating with a threaded part arranged on the projecting part of the internal part, which thread makes it possible to move the ring relative to said internal part, which ring comprises a ramp in the form of a truncated cone, which cooperates with the comb or combs, which ramp positions and locks said combs in the active position, immobilizing said internal part and the external part with respect to one another.

 Still according to the invention, the internal and external parts comprise means for immobilizing in rotation one with respect to the other, consisting of complementary grooves arranged on each of them.

 According to a preferred arrangement of the invention, the internal and external parts are made of thermoplastic material, preferably consisting of two identical parts assembled according to an axial joint plane before being mounted and immobilized by any appropriate means on the corresponding tubes constituting the base.

 According to another arrangement of the invention, the extension of the internal part comprises a tongue housed in a groove in the external part, which extends beyond the combs and the end of which is provided with a lug which makes it possible to retain the ring when the latter is in the unlocking position of said combs.

 According to another arrangement of the invention, at least one of the grooves in the external part, includes a marking serving as a system for locating the position of the tubes relative to one another, to facilitate adjustment of the height of the base, which marking is arranged in the groove where the retaining tab of the ring moves, which tab acting as a cursor.

 The invention will be further detailed with the aid of the following description and of the appended drawings, given by way of indication, and in which: - Figure 1 shows a table whose base consists of a vertical leg and two inclined legs each provided at their end with a wheel arranged in door-to-4; - Figure 2 shows the lower part of the vertical base of the table shown in Figure 1; - Figure 3 shows the lower part of the inclined base of the table shown in Figure 1; - Figure 4 shows, in perspective, with the partially cutaway ring, the connecting area of the two parts associated with the tubes constituting the base; - Figure 5 shows a longitudinal half-section of the adjustment system at one of the locking combs; - Figure 6 shows the comb in the inactive blocking position; - Figure 7 is a longitudinal half-section at the retaining tab of the ring; - Figure 8 shows the ring in the inactive position, retained by the lug of the tongue; - Figure 9 shows a section on 9-9 of Figure 7 showing a portion of the external part in strong lines and the rest in thin dashed lines; - Figure 10 shows a section along 10-10 of Figure 5 showing part of the internal part in strong lines and the rest in thin dashed lines.

 The table shown in Figure 1 has a vertical leg 1 at one of its ends and two legs 2 which are each inclined relative to the normal and which each have, at their lower end, a roller 3 arranged in overhang .

 Each of these feet comprises an upper tube 4 whose diameter is greater than that of the lower tube 5, which lower tube comprises either a shoe 6 as shown in FIG. 2, or a roller 3 as shown in FIGS. I and 3.

 The connection system 7 between the tubes 4 and 5 is detailed in the following figures. It comprises a pair of parts of generally cylindrical shape and in particular: - a part 10 known as an external part, associated with the lower tube 5 covering its upper end, - a part II not visible in FIGS. 1, 2 and 3, known as the internal part , associated with the tube 4, housed in its lower part, and in addition - a ring 12 associated with the internal part 11, which is therefore located at the lower part of the tube 4, which ring makes it possible to activate or deactivate the means of connection system blocked.

 The connection and adjustment system is such that it makes it possible to vary the height of the plate between a minimum and a maximum according to the standards, that is to say between 680 and 760 mm.

 FIG. 4 represents the connection and adjustment system, in perspective with a cut-away part at the level of the ring 12 to show the lower part of the internal part 11, which lower part projects beyond the tube 4.

 The external part 10 and the internal part 11 have grooves 13 and 14 for example, which allow these two parts to slide relative to each other along the axis of the tubes, immobilizing them in rotation one compared to each other.

 The external part 10 comprises, in the groove 13, indications in figures which allow the operator to adjust, as necessary, the height of the base. Another groove 15 has marks in the form of graduations 16, which constitute subdivisions of the figures mentioned in the groove 13.

 The graduations 16 are located in the groove 15 as is a slider 17 which allows the operator to precisely adjust the position of the external part 10 relative to the internal part 11, which slider 17 is located in the extension of the internal part 11, in its part which projects beyond the tube 4.

 This slider 17 is built on a flexible tongue 18 and it also has another function, detailed in particular in FIGS. 7 and 8. It in fact allows, thanks to a lug 19, to retain the ring 12 when this ring is in the inactive locking position.

 The parts 10 and 10 are locked together by means of a notch 20 arranged in the form of several longitudinal strips, delimited by generators, on the external contour of said external part 10, which notch 20 cooperates with the combs 21 which are fitted on the internal part 11, in its lower part and in particular in its part which projects beyond the tube 4.

 These combs 21 are provided with teeth 22 which cooperate with the notching 20. These combs 21 are implemented by means of the ring 12 and in particular of a ramp 23 in the form of a truncated cone arranged on the internal bore of said ring, which ramp 23 cooperates with the lower edge 24 of the comb 21, to hold the teeth 22 in the notch 20 or release said comb which allows the operator to move the part 10 relative to the part II freely.

 The combs 21 are relatively flexible to move apart radially. They are separated by an axial groove 25 from the rest of the lower part of the internal part 11.

 FIG. 5 represents, in a more detailed manner, a half-section of the base at the level of the connection system and in particular of one of the combs 21.

 FIG. 7 represents a half-section of the same part of the base, but at the level of the cursor 17.

 In these two figures we find the upper tube 4 of large diameter in which is fitted the inner ring 11. This ring 11 is immobilized on the end of the tube 4 by means of a flange 26; the two parts are assembled relative to each other by gluing and / or riveting.

 The lower tube 5 is fitted into the external part 10. The external part 10 has at its upper part a peripheral flange 27 which serves as a stop for the upper end of the tube 5.

 FIG. 5 represents a comb in the active blocking position, that is to say that its teeth 22 are encrusted in the notch 20 arranged on the external part 10. The comb 21 is held in this position by the ring 12. This ring 12 comprises an internal thread 29 at its upper part, which cooperates with a thread arranged under the collar 26 on the periphery of the internal part 11. When the ring is screwed as shown in FIG. 5, in abutment under the collar 26, the ramp 23 of the ring presses the end 24 of the comb 21 to hold this comb and in particular to lock its teeth 22 in the notch 20.

 When the ring 12 is unscrewed, as shown in FIG. 6, the comb 21 is free and, because of its elasticity, its teeth can escape from the notching 20 when the two parts 11 and 10 are displaced one relative to the other axially, under operator effort.

 The elasticity of the combs tends to maintain their teeth 22 in the notches 20, which has the effect of promoting the maintenance of the parts 10 and 11 in a fixed position, stationary with respect to each other.

 When the ring 12 is unscrewed, it tends to escape towards the bottom of the base. This ring is retained in its normal intervention zone, thanks to the lug 19 of the tongue 18, which lug 19 cooperates with the lower edge of the ring 12 and maintains it in the waiting position.

 The ring 12 also includes, at its upper part, a skirt 31 which masks the collar 26 of the internal part II and the lower end of the tube 4.

 The tongue 18, as shown in FIG. 8, is shaped so as to tend to move outward to make its lug 19 cooperate with the lower edge of the ring 12.

 The parts 10 and II are preferably made of molded thermoplastic material. Each part is preferably made up of two identical parts assembled along an axial plane.

 The advantage of this connection system is that it eliminates costly interventions on the tubes 4 and 5 which constitute the base, and in particular the machining work. The parts 10 and 11 as well as the ring 12 do not themselves require any machining work. One of the parts, part 10, is in fact obtained by clipping the half-shells which constitute it, the other part, that is to say part 11, is obtained by gluing the half-shells and the 'and the other parts are fixed by riveting on the tubes 4 and 5.

 FIG. 9 partially represents the external part 10 and in particular, in bold lines, half of this part 10 cooperating with one half of the internal part 11 which is shown in thin dashed lines.

 Half of the part 10 is produced by molding a thermoplastic material. It is assembled with another identical half by means of a clipping system comprising hooks arranged at the joint planes of each of the parts constituting the part 10.

 There is a hook 35 at the top of the drawing of the half-piece 10 shown in strong lines, and the same hook shown in thin dashed lines at the bottom of the half-piece 10.

 This hook cooperates with a lug 36 shown in strong lines at the bottom of the drawing of the half-piece.

 These hooks 35 also appear in FIG. 4 in the groove 15 of the external part 10.

 The outer periphery of the part 10 has grooves such as for example the groove 15 in which there are the graduations 16 which cooperate with the cursor 17, and the groove 13 in which there are the figures indicating the height of the plate.

 These grooves 13 and 15 cooperate with the grooves arranged on the internal part 11 such as for example the groove 14 which covers the longitudinal edges 36 and 37, which edges are separated by the joint plane 38 which is found between the two half parts forming the external part 10.

 These grooves make it possible to immobilize in rotation the external part 10 and the internal part II while ensuring precise guidance in translation.

 We also note that the half-pieces 10 are offset by 90 "relative to the half-pieces 11, like their joint planes 38 and 39, respectively.

 The notch 20 is hollowed out on the part 10 on either side of the assembly plane 39 of the half-pieces 11. This notch is arranged on either side of a longitudinal strip 40 which is centered on the plan 39.

 The comb 21 and in particular the teeth 22 appear in FIG. 10 in strong lines, on the half-piece 11. The teeth 22 cooperate with the notch 20 of the part 10 which is shown in thin dashed lines.

 The part It consists of two parts assembled at the joint plane 39. On the one hand the half-part has a groove 41 and, on the other side, a longitudinal stud 42 which constitutes the female part.

 The half-pieces are preferably assembled by gluing.

 Note also in FIG. 10 the collar 26 which serves as a stop for the tube 4 of the base as well as the cursor 17 shown in dotted lines.

 Similarly, there is the groove 25 delimited by two dotted lines, which isolates the part of the part 11 where the combs 21 are located from the rest of said part so as to offer these combs 21 a certain flexibility with respect to the rest of the part and allow the elastic escape of the teeth 22 relative to the notch 20 arranged on the external part 10.

 Still in FIG. 10, there is also an orifice 43 which allows, for example, to house a rivet, not shown, to complete the assembly between the internal part 11 and the tube 4.

 To improve the assembly between the external part 10 and the tube 5, the part 10 may include in its internal bore, bosses 44 whose thickness gradually increases to favor the jamming of the tube inside the part 10.

 The graduations 16 and the numerical marks correspond to the notch 20.

They vary according to the destination of the base. Indeed, for a vertical foot, the graduations are millimeter while for an inclined foot, they are adapted to the inclination of the foot.

Claims (8)

- CLAIMS  1.- Height-adjustable base, consisting of a pair of tubes (4, 5), of different diameters, telescopic, characterized in that it comprises, interposed between said tubes, a connection and adjustment system (7) comprising a pair of tubular parts (10, 11), associated respectively with said base tubes, which parts provide guidance in translation and are immobilized in rotation with respect to each other and they comprise means for blocking the movement of translation, implemented by means of a movable ring (12) integral with one of said parts, which ring operated by the operator, makes it possible to lock or unlock said parts (10,11) one relative to the 'other  2.- base according to claim 1, characterized in that it comprises: - an internal part (11) fixed to the end of the tube (4) of large diameter, - an external part (10) fixed to the end of the tube (5) of small diameter, - a movable ring (12) associated with said internal part (11), mounted on an extension of said internal part, which projects outside the large diameter tube.  3.- base according to any one of claims 1 or 2, characterized in that the external part (10) has a notch which extends in the form of strips on the external periphery of said part, between a pair of generators, which notch cooperates with a comb (21) shaped on the internal part (11), at its extension, which comb, flexible, is placed in the active locking position by means of the movable ring (12).  4.- base according to claim 3, characterized in that the ring (12) has a threaded internal part cooperating with a thread arranged on the periphery of the extension of the internal part (11), which ring also includes a ramp (23) in the form of a truncated cone which cooperates with the end (24) of the comb (21) to place the teeth (22) of the latter in the active locking position, cooperating with the notch (20) of the external part (read) .  5.- base according to any one of claims 1 to 4, characterized in that the external (10) and internal (11) parts comprise means which make it possible to immobilize them in rotation relative to one another, made up of complementary grooves arranged on each of them.  6. A base according to claim 5, characterized in that the extension of the internal part (11) comprises a tongue (18) forming a cursor, housed in a groove (15) of the external part, which cursor extends over the beyond the combs (21) and its end is provided with a lug (19) which makes it possible to retain the ring (12) when the latter is in the unlocked position.  7.- base according to claim 6, characterized in that at least one of the grooves (15) of the external part (10) has a marking or marking for adjusting the position of the tubes (4 and 5) I ' one with respect to the other, which marking-identification cooperates with the cursor (17) which extends the lower part of the internal part (11).  8.- base according to any one of claims 1 to 7, characterized in that the external parts (10) and internal (11) are made of plastic material, each consisting of two identical parts obtained by molding, assembled according to a plane axial (38, 39) respectively.