EP3570705B1 - Sit-stand table - Google Patents

Description

The invention relates to a sit-stand table. The sit-stand table according to the invention can be used particularly advantageously as a sit-stand office work table.

The term sit-stand table means a table whose height can be adjusted quickly and comfortably for either sitting or standing work - especially office work.

At the moment, sit-stand office desks are nowhere near as common as would be sensible for health reasons - and thus indirectly also for economic reasons. The main reason for this is that sit-stand office work tables, if they meet the usual functional requirements, are predominantly perceived as unattractive and expensive.

The lack of beauty is mostly due to the fact that the table frames are relatively bulky for reasons of stability, that for reasons of stability and complexity there are hardly any four-leg frames available, but only tables with a central column or with two side panels, and that some tables need a visible electrical supply line . The costs, which are perceived as high, are caused by expensive components and complex work processes during assembly.

The patent documents JPH0511834U and DE102015207351 each disclose a sit-stand table with a height-adjustable table frame.

The main object of the invention is to propose a construction for a sit-stand table equipped with four legs, the legs and other frame parts of which can be designed as slim and delicate as these, while complying with the usual market standards for function, stability and robustness Parts of tables that can only be used while seated.

An important secondary task is to keep the sum of the costs for the procurement of components and for their assembly so low that the sit-stand table can be more cost-effective than currently available seating despite the four legs and the slim yet stable construction. Standing tables.

• Der Sitz-Steh-Tisch weist Beine auf, welche jeweils einen unteren und einen oberen Beinteil aufweisen, welche als in vertikaler Richtung ausgerichtete Hohlprofile ausgebildet und in vertikaler Richtung ineinander teleskopierbar sind, wobei die Querschnittsfläche des unteren Beinteils durch die Querschnittsfläche des oberen Beinteils umfasst ist.
• Die oberen Beinteile sind starr mit einem hohlen, horizontal verlaufenden Querträger verbunden und sind gemeinsam mit diesem Teil eines in sich starren Tischgestells, welches gegenüber den unteren Beinteilen in der Höhe verschiebbar ist und an welchem eine Tischplatte oben befestigt ist.
• Teleskopische Relativbewegung zwischen jeweils einem unteren und einem oberen Beinteil ist durch Zugmittel - wie typischerweise Seile - antreibbar, welche sich in die Hohlräume der Profile und des Querträgers erstrecken.
• Die Bewegung von Zugmitteln, welche das Anheben der oberen Beinteile gegenüber den unteren Beinteilen antreibt, ist ihrerseits durch eine vorgespannte elastische Feder antreibbar, welche im inneren des Querträgers angeordnet ist.

To solve the problem, a sit-stand table is assumed according to the following combination of features known per se:

• The sit-stand table has legs which each have a lower and an upper leg part, which are designed as hollow profiles oriented in the vertical direction and are telescopic into one another in the vertical direction, the cross-sectional area of the lower leg part being encompassed by the cross-sectional area of the upper leg part.
• The upper leg parts are rigidly connected to a hollow, horizontally extending cross member and, together with this part, are an inherently rigid table frame which is vertically displaceable with respect to the lower leg parts and to which a table top is attached.
• Telescopic relative movement between a lower and an upper leg part can be driven by traction means - such as typically ropes - which extend into the hollow spaces of the profiles and the cross member.
• The movement of traction means, which drives the lifting of the upper leg parts with respect to the lower leg parts, can in turn be driven by a pretensioned elastic spring which is arranged in the interior of the cross member.

• Der Sitz-Steh-Tisch weist vier Beine auf.
• Der Querträger ist mit den oberen Beinteilen jeweils sowohl über einen Seitenträger starr verbunden, welcher zwei obere Beinteile starr verbindet und mit dem Querträger starr verbunden ist, als auch über jeweils eine Diagonalstrebe, welche unmittelbar mit dem jeweiligen oberen Beinteil und mit dem Querträger starr verbunden ist, wobei die Verbindung mit dem Querträger in einem Abstand zur Verbindung des

As a further development according to the invention, the following additional features are proposed:

• The sit-stand table has four legs.
• The cross member is rigidly connected to the upper leg parts via a side member, which rigidly connects two upper leg parts and is rigidly connected to the cross member, as well as via a diagonal strut, which is directly rigidly connected to the respective upper leg part and to the cross member , the connection with the cross member at a distance from the connection of the

• Die Verbindungen des oberen Beinteils mit dem Seitenträger und mit der Diagonalstrebe sind Schweißverbindungen.
• Die Zugmittel für den Antrieb der Teleskopbewegung zwischen dem unteren und oberen Beinteil verlaufen längs durch die mit dem oberen Beinteil verbundenen Diagonalstrebe, welche als Hohlprofil ausgebildet ist, hindurch.

Cross member with the side member lies.

• The connections of the upper leg section with the side support and with the diagonal brace are welded connections.
• The traction means for driving the telescopic movement between the lower and upper leg part run longitudinally through the diagonal strut connected to the upper leg part, which is designed as a hollow profile.

• auch bei sehr schlanken Ausführungsformen der sichtbaren Bein- bzw. Gestellteile eine sehr gute mechanische Stabilität des Sitz-Steh-Tisches erreichbar ist,
• ein auf Elastizität einer elastischen Feder und Übersetzung durch Zugmittel basierendes Antriebsprinzip - welches an sich robust und kostengünstig ist - gut verwirklichbar ist,
• Funktionskomponenten des Antriebes, sonstige Anbauteile und Komponenten des Tischgestells einfach herstellbar und einfach montierbar ausgebildet sein können.

The advantages of the arrangement according to the invention are that

• A very good mechanical stability of the sit-stand table can be achieved even with very slim designs of the visible leg or frame parts,
• a drive principle based on the elasticity of an elastic spring and translation by traction means - which is robust and inexpensive in itself - can be easily implemented,
• Functional components of the drive, other add-on parts and components of the table frame can be designed to be easy to manufacture and easy to assemble.

• Fig. 1 zeigt eine Schnittansicht mit zum Querträger 2 paralleler Blickrichtung insbesondere auf den Querträger 2 eines beispielhaften erfindungsgemäßen Sitz-Steh-Tisches.
• Fig. 2., Fig. 3 und Fig. 4 zeigen in perspektivischer Ansicht vorteilhaft ausgebildete Anbauteile 3, 4, 5 an den Querträger eines erfindungsgemäßen Sitz-Steh-Tisches.
• Fig. 5 veranschaulicht in seitlicher Schnittansicht durch Teile eines Tischgestells das Grundprinzip des vorgeschlagenen Antriebes, welches für erfindungsgemäße Sitz-Steh-Tische wie für Sitz-Steh-Tische gemäß dem Stand der Technik gleichermaßen gilt.
• Fig. 6 zeigt in Schrägrissansicht vorteilhaft ausgebildete beispielhafte Teile, welche bestimmungsgemäß dem Antrieb der Höhenverstellbarkeit dienen und sich im Inneren eines Beines eines erfindungsgemäßen Sitz-Steh-Tisches befinden.
• Fig. 7 zeigt eine horizontale Schnittansicht durch ein vorteilhaft ausgebildetes Tischbein eines beispielhaften erfindungsgemäßen Sitz-Steh-Tisches.
• Fig. 8 zeigt die in Fig. 7 angedeutete vertikale Schnittansicht durch das Tischbein von Fig. 7.
• Fig. 9 zeigt in Schrägrissansicht einen Seitenteil eines beispielhaften erfindungsgemäßen Sitz-Steh-Tisches.
• Fig.10 zeigt das in Fig. 9 durch einen Kreis umrundete Detail vergrößert.
• Fig. 11 und Fig. 12 zeigen eine horizontale Schnittansicht auf einen vorteilhaft ausgebildeten Übergangsbereich zwischen einer Diagonalstrebe und dem Querträger eines beispielhaft ausgebildeten erfindungsgemäßen Sitz-Steh-Tisches.
• Fig. 13 zeigt das Tischgestell eines beispielhaften erfindungsgemäßen Sitz-Steh-Tisches in Ansicht von oben.
• Fig. 14 zeigt die in Fig. 13 angedeutete vertikale Schnittansicht durch einen Seitenträger des beispielhaften erfindungsgemäßen Sitz-Steh-Tisches von Fig. 13.
• Fig. 15 veranschaulicht wie Fig. 5 in seitlicher Schnittansicht durch Teile eines Tischgestells das Grundprinzip des vorgeschlagenen Antriebes, welches für erfindungsgemäße Sitz-Steh-Tische wie für Sitz-Steh-Tische gemäß dem Stand der Technik gleichermaßen gilt.
• Fig. 16 zeigt in Draufsicht eine vorteilhafte Vorrichtung für das Arretieren bzw. Lösen der Höhenverstellung eines beispielhaften erfindungsgemäßen Sitz-Steh-Tisches.
• Fig. 17 zeigt in Seitensicht eine Vorrichtung für das von Bedingungen abhängige automatische Auslösen des Arretierens der Höhenverstellung eines beispielhaften erfindungsgemäßen Sitz-Steh-Tisches.

The invention, including many advantageous further developments, is illustrated with the aid of schematic drawings. Some of these advantageous developments can also be used advantageously on tables that are not sit-stand tables with four legs and are inventive innovations.

• Fig. 1 shows a sectional view with a direction of view parallel to the cross member 2, in particular onto the cross member 2 of an exemplary sit-stand table according to the invention.
• Fig. 2 ., FIGS. 3 and 4 show a perspective view of advantageously designed add-on parts 3, 4, 5 on the cross member of a sit-stand table according to the invention.
• Fig. 5 illustrates in a side sectional view through parts of a table frame the basic principle of the proposed drive, which applies equally to sit-stand tables according to the invention and sit-stand tables according to the prior art.
• Fig. 6 shows, in an oblique view, advantageously designed exemplary parts which, as intended, serve to drive the height adjustability and are located inside a leg of a sit-stand table according to the invention.
• Fig. 7 shows a horizontal sectional view through an advantageously designed table leg of an exemplary sit-stand table according to the invention.
• Fig. 8 shows the in Fig. 7 indicated vertical sectional view through the table leg of Fig. 7 .
• Fig. 9 shows in an oblique view a side part of an exemplary sit-stand table according to the invention.
• Fig. 10 shows that in Fig. 9 enlarged by a circle encircled detail.
• Figures 11 and 12 show a horizontal sectional view of an advantageously designed transition area between a diagonal strut and the cross member of an exemplary sit-stand table according to the invention.
• Fig. 13 shows the table frame of an exemplary sit-stand table according to the invention in a view from above.
• Fig. 14 shows the in Fig. 13 Indicated vertical sectional view through a side support of the exemplary sit-stand table according to the invention from FIG Fig. 13 .
• Fig. 15 illustrates how Fig. 5 in a side sectional view through parts of a table frame the basic principle of the proposed drive, which applies equally to sit-stand tables according to the invention and sit-stand tables according to the prior art.
• Fig. 16 shows in plan view an advantageous device for locking or releasing the height adjustment of an exemplary sit-stand table according to the invention.
• Fig. 17 shows a side view of a device for the condition-dependent automatic triggering of the locking of the height adjustment of an exemplary sit-stand table according to the invention.

FIGS. 1 to 4 deal with the proposal according to the invention for tables which have a table top 1 and a metal base frame with a hollow cross member 2 running horizontally below the table top 1 to connect attachments 3, 4, 5 to the cross member 2 in a particularly advantageous manner. The advantages are: inexpensive individual parts, positions can be varied very flexibly, extremely simple work processes during assembly. This proposal according to the invention is applicable not only to sit-stand tables, but also to all tables which have a hollow cross member below the table top.

According to the invention, the attachment 3, 4, 5 is positively hooked with the upper area of the cross member 2 against movement downwards and in the direction of a lateral partial jacket surface 6 of the cross member 2 and the attachment 3, 4, 5 has a stop surface 7, with which it rests on the lateral cross member 2 on the lateral partial jacket surface 6 on the outside.

In Fig. 1 a table top 1, a cross member 2 running underneath and an attachment 3 are shown.

The cross member 2 is part of the underframe of the table, connects left and right side parts of the underframe and is essentially a hollow metal profile, typically a C-profile made of folded sheet steel. In the typical application of the invention, the cross member 2 has an opening 8 on the upper side of the shell and it contains, among other things, parts which are used for the drive or for weight compensation when the table is adjusted in height. Such parts (none of them shown) can be, for example, elastic springs, gas pressure springs, motors, drive spindles, ropes, rollers, slides and slide guides, motion dampers, etc. The opening 8 is usually covered by a removable cover (not shown).

Whatever the case, the table top 1 is either completely rigidly connected to the cross member 2 or connected to the cross member 2 in such a way that it can only be moved horizontally with respect to this.

In addition to the functions already discussed, it is a function of the cross member 2 to carry add-on parts 3, which are required in the area directly under the table top 1. Typically, these add-on parts 3, 4, 5 or are these add-on parts 3, 4, 5 parts such as panel mounting fittings, operating levers for height adjustment, operating levers for moving panels, cable duct brackets, socket holders, screens, etc.

The essential features according to the invention are that the attachment 3 has a hook extension 9, with which it is hooked from above with the upper part of the cross member 2 against movement on a lateral partial jacket surface 6 of the cross member 2, and that the attachment 3 has a stop surface 7 has, with which it rests on said lateral partial jacket surface 6 on the outside.

In the advantageous construction shown, the hook extension 9 is hooked to an edge 10 of the opening 8 located at the top of the cross member 2, facing the lateral partial jacket surface 6.

How out Fig. 1 As can be seen immediately, the connection formed in this way between cross member 2 and attachment 3 can neither be produced nor released as long as table top 1 is on cross member 2 as shown. The attachment or detachment of the attachment 3 on or from the cross member 2 requires that the attachment 3 around its hook extension 9 located on the edge 10 in that height range is pivoted downwards or upwards, on which the table top 1 is located, if it is properly mounted on the cross member 2.

As in the synopsis of Fig. 1 With Fig. 2 As can be clearly seen, the attachment 3 is not just a flat sheet metal, but it also extends somewhat parallel to the longitudinal direction of the cross member 2 and it has two mutually aligned hook extensions 9 that are spaced apart in the direction of the cross member 2. As a result, in the assembled state, it cannot be pivoted about vertical axes with respect to the cross member 2.

The in FIGS. 1 and 2 The outlined attachment 3 is only fixed by the hook extensions 9 and the stop surface 7 on the cross member 2.

In order to positively block the displaceability of the attachment 3 along the cross member 2, the cross member 2 can have an indentation on that part of the edge 10 of the opening 8 on which the attachment 3 is to be hooked, on the bottom of which the hook extension 9 rests and on which Flanks he comes to a stop against movement along the profile direction of the cross member 2.

If necessary, there are of course a variety of ways to fix an attachment 3 fastened according to the invention on the cross member 2 beyond the minimum size according to the invention described at the beginning, so that the attachment 3 does not just hang loosely on the cross member 2 when the table top 1 is removed. FIGS. 3 and 4 illustrate exemplary possibilities for this:

The attachment 4 according to Fig. 3 has two projections 11 which protrude from its intended stop surface 7. The inventive and intended matching cross member 2 has at those points of that lateral partial jacket surface 6 to which these projections 11 protrude when the attachment 4 is mounted, recesses into which these projections 11 protrude and ideally engage somewhat.

The attachment 5 according to Fig. 4 has a tongue 12 which, as intended, together with the hook extensions 9 also required according to the invention, delimits a type of mouth which, when the attachment 5 is mounted on the matching cross member 2, clasps part of the cross member 2 from above and below under elastic pretension. For this purpose, the tongue 12 can be designed as a whole as a flexible tongue, or, as indicated in the drawing, have a separate flexible tongue 13 protruding from it.

If a recess or depression is attached to the underside of the matching cross member 2 at the point at which the spring tongue 13 comes to rest, the spring tongue 13 can snap into this recess or recess and thereby the connection between cross member 2 and attachment 5 approximately or make completely unsolvable. The attachment part 5 can thereby also be hooked in a form-fitting manner with the lower region of the cross member 2 against movement in the longitudinal direction of the cross member 2.

As an alternative to the in Fig. 1 It is also possible within the scope of the invention not to hook an attachment 3, 4, 5 with the edge 10 of an opening 8 on the cross member 2, but with another boundary surface facing away from said partial jacket surface 6 of a rigid with the cross member 2 connected part or area. For example, sheet metal tabs could be punched free from the upper region of the cross member 2 and bent outwards and an attachment part could be hooked onto these sheet metal tabs. For example, the cross member can also be designed as an extruded profile made of aluminum and have a protruding profile wall or a groove on its outer surface, on which an attachment is hooked according to the invention. It is important that the hook on the attachment is designed in such a way that the attachment can only be hooked onto the cross member 2 by a rotary movement from above and the hook can only be released by an upward rotary movement.

Fig. 5 and Fig. 6 deal with the inventive arrangement of rollers for height adjustment by means of traction means (typically rope) in a telescopic table leg. The advantages are inexpensive individual parts and, above all, extremely simplified assembly, especially when the legs are very slim. The on hand of Fig. 5 and Fig. 6 The construction described is also advantageous and inventive when it is used on a sit-stand table which has fewer than four telescopic legs. If the sit-stand table has four legs, however, the construction is particularly valuable because the higher number of legs means that the work time saved by simple assembly is very high, and because the legs of four-leg tables tend to be made as slim as possible, which is otherwise the case Assembly could be quite difficult.

Fig. 5 serves to understand the basic mode of operation of a telescopic table leg supported by traction means - regardless of whether it is designed according to the prior art or according to the present invention.

Fig. 5 shows a table frame 14, an upper leg part 15 rigidly connected to it and a lower leg part 16 arranged telescopically to this. The leg parts 15, 16 are vertically aligned hollow profiles, the lower leg part 16 having a smaller cross-sectional area than the upper leg part 15 and in the upper leg part 15 is inserted from below and is vertically displaceable in this.

Three rollers 17, 18, 19 are each held so as to be rotatable about a horizontal axis, the axis of rotation being held immovably with respect to the upper leg part 15. Two rollers 17, 18 are arranged in the vicinity of the upper end of the upper leg part 15. The third, lower roller 19 is located in a spatial area encompassed by the lateral surface of the lower, inner leg part 16. The lower roller 19 is connected to the upper leg part 15 via a support rod 20, which is indirectly rigidly connected to the upper leg part 15, runs parallel to the inside of the two leg parts 15, 16 and from above into the lower leg part 16 protrudes.

Around an upper roller 17, 18, through the upper leg part 15 vertically, into the lower leg part 16 from above, two flexible traction means 21, 22 (for example ropes) run, each with one end at one above the lower Roller 19 lying connection point 23 are connected to the lower leg part 16. A traction means 21 leads in its course from the upper roller 17 also around the lower roller 19 below. When this traction means 21 is pulled in the area of the table frame - and the other traction means 22 is released - the lower leg part 16 is moved downward relative to the upper leg part 15, and the table height adjustment is thus extended. If, on the other hand, the second traction mechanism 22 is pulled in the area of the table frame - and the other traction mechanism 21 is released - the lower leg part 16 is moved upwards relative to the upper leg part 15 and the table height adjustment is thus retracted. Pulling on the traction means 21 can also be used to brake or block the retraction of the lower leg part 16, which is driven by the weight of the upper table part including the load arranged on it.

Fig. 6 shows a concrete exemplary embodiment according to the invention of the arrangement of the already mentioned rollers 17, 18, 19 on the already mentioned support rod 20. The axis of the lower roller 19 is directly held by two holding bodies 24, which in the assembled state preferably one behind the other in the axial direction of the lower roller 19 lie and together encompass the lower roller 19 in a plane lying parallel to the roller axis.

The gap between the edges of the running surface of the lower roller 19 and the said enclosure should be narrower than the cross-sectional dimension of the traction means 21 in the radial direction of the roller. This makes it impossible for the traction means 21 to fall off the lower roller 19 when it is enclosed.

Since the lower roller 19 is jointly encompassed by two holding bodies 24 and not by one holding body alone, it is possible to first place the traction means 21 around the running surface of the lower roller 19 during assembly and only then the two holding bodies 24 on the roller 19 to attach and thus to close the said enclosure. The traction means does not need to be laboriously threaded through a gap between the enclosure and the roller.

Since the two holding bodies 24 lie one behind the other in the axial direction of the lower roller 19, the assembly is very simple because the holding bodies 24 can be plugged together by an axially parallel movement on one another and on the roller axis. The mounting of the roller axis on the holding bodies is therefore very robust and the two holding bodies can be designed to be identical to one another, which also simplifies their production and the logistics associated with them.

In an advantageous further development, the connection between the holding bodies 24 and the support rod 20 is a plug connection which can be established by relative movement of the holding bodies 24 in a direction parallel to the direction of the support rod 20 towards the lower end of the support rod 20. This can be assembled quickly, the plug connection is secured in the assembled state by the tension of the traction means 21 on the lower roller 19.

In an advantageous further development, the two upper rollers 17, 18 are held on the upper face of the support rod 20 in a manner analogous to the lower roller 19 on two further holding bodies 25, the two upper rollers 17, 18 being arranged on a common axis. For this purpose, the upper holding bodies 25 are connected in a manner analogous to the lower holding bodies 24 with the support rod 20 by a plug-in connection, which is established by moving the holding bodies 25 parallel to the direction of the support rod 20 towards the upper end face of the support rod is. This further simplifies assembly. As a support rod 20, a flat cut hollow profile can thus easily be used.

The lower holding bodies 24 are preferably designed as sliding blocks in the lower, inner leg part 16. This gives the construction very good stability with little material expenditure. For this purpose, the holding bodies 24 must have surface areas 26 which are dimensioned in such a way that they rest against the inner circumferential surface of the lower leg part 16 designed as a hollow profile without play but largely without pressure.

The upper holding bodies 25 are preferably dimensioned in such a way that they are inserted without play in the upper leg part 15 by means of a press fit. As shown, this can be done by means of extensions 27, which are formed on the upper holding bodies 25 and protrude radially from these in the assembled state with respect to the axis of the support rod 20 and protrude to the inner surface of the upper leg part 15 and bear there under pressure. If - as sketched - the projections 27 are slightly pointed or rounded at the front, any small protrusion of their length is simply scraped off to exactly the right amount during assembly during the insertion of the upper holding body 25 into the upper leg part 15.

In the fully assembled state, the assembly comprising the support rod 20 and the holding bodies 24, 25 as well as the rollers 17, 18, 19 rests with the uppermost surface of the upper holding bodies 25 under pressure on an inner surface of the table frame 14 from below. The compressive force required for this is due to the pull of the pulling means 21 running around the lower roller 19 ( Fig. 5 ) caused.

FIGS. 7 and 8 deal with the inventive arrangement of sliding linings for sliding guidance of the telescopic leg parts 15, 16 of the telescopic table legs. The advantages are inexpensive individual parts and, above all, a slim design with very good mechanical stability and permanently good function. The design is particularly valuable for sit-stand tables with four legs, as the slim design is particularly important; But it is also advantageous and inventive on sit-stand tables with fewer than four legs.

Fig. 7 shows the essential parts for understanding the invention in cross-sectional view. The cross-sectional area of the upper leg part 15, which is designed as a hollow square profile for example, comprises the cross-sectional area of the lower leg part 16, which is designed to match this as a hollow square profile with a smaller cross-sectional area. The leg parts 15, 16 do not touch one another, but between the two cross-sectional areas of the two leg parts 15, 16 an annular gap 28 runs around the profile of the lower leg part 16.

Fig. 8 shows in the in Fig. 7 Vertical sectional view indicated by arrows, in each case one lateral surface side of the upper leg part 15 and the lower leg part 16 at the height overlap area of the two leg parts 15, 16, with the leg parts 15, 16 extended to the maximum extent.

The annular gap 28 between the leg parts 15, 16 is bridged at several points by sliding linings 29, 30, 31. Typically, the sliding linings 29, 30, 31 are strips equipped with an adhesive layer on one side, made of an essentially wear-resistant plastic. The sliding linings 29, 30 are glued to the outer circumferential surface of the lower (inner) leg part 16; The sliding linings 31 are glued to the inner surface of the upper leg part 15.

In Fig. 8 It can be clearly seen that the sliding linings 31 belonging to this are located on the outer leg part 15 at the lowest height area of the outer leg part 15, while the sliding linings 29 belonging to the inner leg part 16 are located at the uppermost longitudinal area of the lower leg part 16. The sliding linings 29, 30 belonging to the inner leg part 16 preferably extend at least approximately over that height range of the inner leg part 16 which is still encompassed by the outer leg part 15 when the leg parts are telescopically extended to the maximum and not beyond this height range.

Since, when the telescope is extended, the height range over which the sliding linings 29, 30 attached to the inner leg part 16 extend, is covered with that height area and because, during the telescopic movement of the leg parts, the sliding linings 29, 30 fixed to the inner leg part 16 do not coincide with those on the outer leg part 15 fixed sliding linings 31 are allowed to collide, are shown in cross-sectional view ( Fig. 7 ) the sliding linings 31 attached to the outer leg part 15 are arranged at a distance from the sliding linings 29, 30 attached to the inner leg part 16.

In Fig. 7 It is indicated that the sliding linings 29 arranged on the inner leg part 16 are stronger (that is, they apply more to the outer circumferential surface of the leg part 16) than the sliding linings 30 arranged on the inner leg part 16 as well. This fact results from a particularly preferred manufacturing method:
Originally the two sliding linings are equally strong, namely together slightly greater than the difference in size between the inner dimensions of the upper (outer) Leg part 15 and the outer dimension of the lower (inner) leg part 16, but ideally significantly less than twice as great as this difference in size. These strong sliding linings are first glued onto the inner leg part 16. Then the cross-sectional dimension of the entirety of the lower leg part 16 and the sliding linings arranged on it is reduced so much by milling off individual sliding linings that it fits into the cavity of the upper (outer) leg part 15 without play but without disturbing strong pressure. Those sliding linings arranged on the lower leg part 16, the thickness of which has been reduced for the purpose of adaptation by milling, have in FIGS. 7 and 8 the position number 30; the sliding linings that have not been milled off have item number 29.

The thickness (layer thickness) of the sliding linings 30 arranged at the lower end of the upper leg part 15 is ideally slightly (for example approximately 0.3 mm) less than the average thickness of the annular gap 28.

Figures 9 and 10 deal with the design according to the invention of the side parts 32 of a subframe, essentially formed from hollow metal profiles, of a sit-stand table with four telescopic legs, in which the length adjustment of the telescopic table legs can be driven. According to the state of the art, it was only possible by using profiles with unattractively large cross-sectional dimensions to make the four-legged base of a sit-stand table so stable that when the table is set high and the table top bumps slightly from the side, it does not become too strong Vibrations came. The construction according to the invention makes it possible, under economically sensible framework conditions, to design a sit-stand table with four legs so that both the legs are slim and the base is very stable against elastic deformations and vibrations. In principle, the construction is according to Figures 9 and 10 Not only applicable when the drive for the height adjustment is based on ropes and elastic springs, but also with any other type of drive for the height adjustment of a sit-stand table equipped with four legs. The construction according to Figures 9 and 10 can also be used advantageously and inventive on tables with four legs, which are not height-adjustable at all. Compared to tables according to the state of the art, with the same good stability against elastic deformations and vibrations of the table frame, a slimmer construction of the frame parts suffices.

The side part 32 essentially consists of two upper leg parts 15, a side support 33 and two diagonal struts 34. All these parts are essentially sheet steel square hollow profiles. In each case one end of the side support 33 is welded to the upper end of a leg part 15 and one end of a diagonal strut 34 to form a common corner area 35. The horizontally extending side support 33 and the two diagonal struts 34 together form a horizontally lying triangle, although the sides formed by the two diagonal struts 34 do not quite protrude against one another, so that instead of the corner there is an open area. To form a complete underframe of a table, side parts 32 arranged in mirror image to one another are supported by a cross member (item 2 in Fig. 1 ), wherein the cross member rests with its two end regions on a connecting region 36 on a side member 33 and its vertically lying lateral surfaces rests on the end regions of the diagonal struts 34 facing away from the side members 33.

The invention lies in the special design of the corner area 35, which in Fig. 9 framed by a circle and in Fig. 10 across from Fig. 9 is shown somewhat enlarged.

The ends of the upper leg part 15, the side support 33 and the diagonal strut 34 protruding from this corner area are cut so that the outer surfaces still visible after they have been joined have no openings. At the externally visible lines of contact between said parts, they are rigidly connected to one another throughout, typically welded to one another. For the implementation of energy transmission means from the profile cavity of the diagonal strut 34 into the profile cavity of the leg part 15, the lateral surface part 37 covered by the diagonal strut 34 in the assembled state is opened through an opening - the edge surface of which in Fig. 10 has position number 38. Said energy transmission means are used to extend and retract the telescopic table legs; they can be traction means (ropes) or hydraulic hoses or electrical lines. In the event that the energy transfer means are traction means (ropes), there are rollers 15 in the uppermost height area of the leg parts (position 17, 18 in Fig. 6 ) for their redirection. The axis of rotation of these rollers must then be aligned horizontally and normal to the longitudinal direction of the diagonal struts 34.

It is essential according to the invention that the lateral surface part 37 is at least one third, preferably half the width of that opening, despite this opening The lateral surface side of the leg part 15, of which the lateral surface part 37 is a part, protrudes without interruption to the upper lateral surface side of the side support 33, which covers the upper end face of the leg part 15. It is also of essential importance according to the invention that the lateral surface side of the leg part 15 facing the side support 33 has a lateral surface part 39 which is at least one third, preferably half as wide as this lateral surface side, protrudes without interruption to the upper lateral surface side of the side support 33 and is directly rigidly connected to this - typically by welding.

In that not only the continuously visible leg surface sides of the leg part 15 protrude up to the upper lateral surface side of the side support 33, but also those lateral surface sides which are covered in their upper longitudinal area by the diagonal strut 34 or by the side support 33, the result is that the The cross-sectional shape of the parts that come together in the corner area 35 can hardly be changed (twisted) when bent, which means that the overall structure is significantly more rigid.

So that the lateral surface part 39, which is part of the lateral surface side of the leg part 15 facing the side support 33, can be conveniently welded to the upper lateral surface side of the side support 33, the lateral surface part 39 has a short protruding tongue 40 on its uppermost edge which, as intended, into a the opening 41 located on the upper lateral surface side of the side support 33 protrudes and rests against its lateral surfaces.

Fig. 11 illustrates an advantageous arrangement of a pulley 42 deflecting a traction means 21 (rope) at the transition area between a diagonal strut 34 and the cross member 2 of a sit-stand table according to the invention, the traction means 21 running in the cavity of the parts of the diagonal strut 34 and cross member 2, which are designed as hollow bodies. As with Fig. 9 explains, the diagonal strut 34 connects the upper end of a leg part 15 with the cross member 2. That lateral surface of the cross member 2, on which the diagonal strut 34 abuts, is provided in the part covered by the end face of the diagonal strut 34 with an opening 43 through which the traction means 21 runs.

According to the invention, it is proposed that the axis of rotation of the roller 42 be arranged vertically aligned in the cavity of the diagonal strut 34, and that the running surface of the roller 42 protrudes into the cavity in the cross member 2.

This makes it possible for the traction device 21 in the cross member 2 to run very close to that side wall of the cross member 2 on which the diagonal strut 34 rests on the outside. As a result, the cross member 2 can be made much narrower than would be possible if the roller 42 were mounted in the cross member 2. If it is necessary to deflect the traction device 21 in the cross member 2 once by 180 °, this can be done by means of a roller, the plane of which is parallel to the said side wall of the cross member 2 and thus also takes up very little space in the width of the cross member 2 .

Fig. 12 FIG. 11 illustrates an advantageous method of fastening the axis 44 of the roller 42 to the diagonal strut 34 according to the arrangement of FIG Fig. 11 . The axis 44 is a pin which is formed from three circular cylindrical sections lying one behind the other in the common axis, the middle section having a larger diameter than the two sections at the ends, with the roller 42 - possibly also several rollers - at the middle section. is held rotatably and the middle section is as long as the cavity in the diagonal strut 34 is high. In the installed state, the axis 44 is oriented vertically, its lowest part protrudes into a hole on the lower lateral surface of the diagonal strut 34, the diameter of which is smaller than the diameter of the middle part. The upper part rests with part of its outer surface on the base of an indentation 45 in the end face of the diagonal strut 34. One flank of this indentation 45 is designed as a slender finger 46 made of the material of the diagonal strut 34, in that a further indentation is formed next to the indentation 45 from said end face. (The two indentations can be produced by removing edge-side surface areas of the sheet metal forming the cross member 2, most easily by laser cutting). As soon as the axle 44 with the roller 42 arranged on it is in the in Fig. 12 is the position shown, the finger 46 can be bent towards the indentation 45, whereby the axis 44 is secured against sliding out of the indentation 45. Of course, at the second (lower) end of the axle 44, the holder for the axle 44 can also be designed with such an indentation 45 and such a finger 46.

The assembly method made possible by this version with indentation 45 is extremely material and time-saving.

The indentation 45 runs from its opening side into the non-raised angular area that the traction means 21 ( Fig. 11 ) on the roller 42 includes. This is in operation the axis 44 also held by the tension of the traction means 21 at the base of the indentation 45.

Figures 13 and 14 illustrate an exemplary construction according to the invention for a table frame 47 with four leg parts, which has two side parts 32 and a cross member 2 and wherein the side parts 32 each consist of a side support 33, two diagonal struts 34 and a leg part 15, which are rigidly connected to one another, preferably with one another are welded, as shown by Figures 9 and 10 already described.

The connection method proposed with the construction between the side parts 32 and the cross member 2 can be implemented with extremely little work and material expenditure and nevertheless offers very good stability.

• dass die beiden vom Seitenträger 33 abgewandt liegenden Enden der beiden Diagonalstreben 34 an jeweils eine Seitenmantelfläche des Querträgers 2 heranragen und mit dieser zumindest punktuell gegen translatorische Relativbewegung unverrückbar miteinander verbunden sind, beispielsweise durch jeweils eine Schraube 48,
• und dass eine Steckverbindung besteht, die durch eine Relativbewegung zwischen dem Querträger 2 und dem Seitenträger 33 in Längsrichtung des Querträgers 2 auf den Seitenträger 33 zu herstellbar ist und nach deren Herstellung der Querträger 2 und der Seitenträger 33 an den Berührungsflächen 49, 50, 51, 52, 53 aneinander anliegen, die Relativbewegungen zwischen den beiden Trägern in den Richtungen aufeinander zu, vertikal in beiden Richtungen und parallel zur Längsrichtung des Seitenträgers 33 in beiden Richtungen, formschlüssig blockieren.

According to the invention, a side part 32 and the cross member 2 are connected to one another in two ways, namely so

• that the two ends of the two diagonal struts 34 facing away from the side support 33 each protrude to a lateral lateral surface of the transverse support 2 and are immovably connected to this at least at certain points against translational relative movement, for example by a screw 48 each,
• and that there is a plug connection which can be produced by a relative movement between the cross member 2 and the side member 33 in the longitudinal direction of the cross member 2 on the side member 33 and after its production, the cross member 2 and the side member 33 on the contact surfaces 49, 50, 51, 52, 53 rest against one another, positively blocking the relative movements between the two carriers in the directions towards one another, vertically in both directions and parallel to the longitudinal direction of the side carrier 33 in both directions.

The connection between the cross member 2 and the side parts 32 can thus be established by plugging together two plug connections and by attaching and tightening four screws.

As with Fig. 14 which the in Fig. 13 The indicated sectional view is clearly recognizable, the plug-in tongues 54, 55, 56 required for the said plug connection can be formed on the cross member 2 as extensions of lateral surface areas of the cross member 2 protruding in the longitudinal direction of the cross member 2. On the side support 33, the receiving areas for the tongues 54, 55, 56 parts of the outside the upper and the lower lateral surface, as well as boundary surfaces of openings in the lateral surface facing the cross member 2.

On the profiles, from which cross members 2 and side members 33 are formed, only laser cuts are required - if at all - to produce the plug-in tongues 54, 55, 56 or the receiving areas.

The lifting movement of the sit-stand table is driven indirectly by an elastic spring - i.e. a spring whose function is based on the elastic deformation of a solid body - is advantageous over other drive methods for several reasons: it is inexpensive, robust, long-lasting, it is necessary No electrical connection line or battery, the course of the spring force over the spring travel is independent of the direction in which the spring travel is traversed, by adjusting the preload of the spring, the force-travel characteristic can be changed in a targeted manner. Unlike e.g. However, gas pressure springs do not provide elastic springs with inherent movement damping. When designing a height adjustment supported by elastic springs, special attention must therefore be paid to avoiding dangerously rapid movements of parts. In order to be able to use elastic springs as drive means for adjusting the height of a sit-stand table, separate safety devices are required to prevent dangerous rapid relative movements between the table frame rigidly connected to the table top and the leg parts that can be moved relative to it and are properly positioned on the floor .

Based on FIGS. 15 to 17 several advantageous safety devices in this regard are explained. These safety devices are advantageously applicable and inventive at all sit-stand tables, regardless of the number of legs, in which the drive of the lifting movement is based on the fact that the drive energy comes from a pretensioned elastic spring and is transmitted to the table legs by traction means.

It is based on the known principle that the relative movement occurring during height adjustment between the table frame rigidly connected to the table top and the leg parts resting on the floor as intended is translated into relative movement between a further part movably held on the table frame and the table frame itself is and that the relative movement of the further part movably held on the table frame can optionally be blocked by an engagement body, in that the engagement body is optionally movable to establish or release a further mechanical connection between the table frame and the movable part guided thereon.

According to the invention it is proposed to provide a part arrangement acting on the engagement body, the effect of which is to move the engagement body into the engaging position and / or fix it in the engaging position depending on a state of the sit-stand table.

In Fig. 15 the stand 47, an upper leg part 15, a lower leg part 16, a coil spring 57 serving as an energy storage device and a transmission mechanism are shown, among other things, from the sit-stand table according to the invention sketched as an example. The outlined exemplary transmission mechanism, which comprises traction means 21, 22 (ropes), rollers 17, 18, 19, 58 and a slide 59 that is linearly displaceable with respect to the frame 47, couples the movement of one end of the spring 57 with relative movement between the rigid and the frame 47 connected upper leg part 15 and the lower leg part 16, which can be telescoped with respect to this. Such and many other transmission mechanisms, which are based on guided movements of parts such as ropes, pulleys, gears, levers, racks, etc., are known in the art from the prior art well known for the spring-assisted height adjustment of tables and therefore need not be discussed further here.

Not shown is a locking device which can typically be actuated by a handle and, depending on the actuation, blocks or releases the mobility of a part of the transmission mechanism and thus fixes the height adjustment or releases it for adjustment.

The part important for the advantageous function explained here, which is held movably guided on the frame 47 and whose relative movement with respect to the frame 47 is coupled with the relative movement of the lower leg parts 16 with respect to the frame 47, is a gear wheel 60 which is coaxial with a central pulley 61 arranged and rigidly connected to this. The movement coupling between movement of the movable lower leg part 16 and the pulley 61 takes place via a cable 62, which is part of the transmission mechanism of movement between the spring 57 and The leg part 16 is guided in several turns around the spiral rope pulley 62, connects the slide 59 and the movable end of the spring 57 and is kept under tension by the tensile force exerted by the spring 57.

According to Fig. 16 An engaging body 63 is part of a locking device which can be actuated via a Bowden cable 64 as a transmission means by a handle (not shown) and, depending on its actuation, blocks or blocks the mobility of a part of the transmission mechanism between the lower leg parts 16 and the spring 57 which supports the height adjustability releases and thus fixes the height adjustment or releases it for adjustment. For this purpose, the engagement body 63 is held on the table frame 47 so as to be linearly displaceable. Depending on its shifting position, it can be brought into or out of engagement with the toothing 66 of the gear 60 with a toothing 65 attached to the end face with respect to its shifting direction, whereby the movement of the gear 60 is blocked or released.

So that when the handle is not actuated, the height adjustability is blocked, the engaging body 63 is then when no actuation takes place by a permanently acting power source - according to Fig. 16 a compressively biased elastic spring 67 - held in the engaged position.

If, with the engaging element 63 locked and the gear 60 blocked, on the gear 60 from the pulley 61 ( Fig. 15 ) a large torque is exerted, it is caused by the fact that the spring force for lifting the frame 47 including the table top and possibly the load on it is set either too strong or too weak. If the lock were released, a dangerously rapid relative movement of the frame 47 with respect to the lower leg parts 16 would be the result.

As the first of two measures described here to prevent this dangerous relative movement, the tooth flanks of the toothing 66 of the gear wheel 60, which is motion-coupled with the table height adjustment, are designed with such high friction to the engaging toothing 65 of the engaging body 63 that when the Gear 60 large force is exerted on the engaging body 63, is prevented by static friction movement of the engaging body 63 away from the gear 60, as long as the engaging body 63 is not pulled strongly.

The second measure relates to the guide 68, which keeps the engagement body 63 guided relative to the frame 47, in particular those guide surfaces 69 which are aligned parallel to the possible sliding direction of the engagement body 63 and against it Support movement in other than sliding directions. The engaging body 20 is forcibly pressed against these guide surfaces 69 when force is exerted on it by the gear 60. According to the invention, these guide surfaces 69 are designed as friction surfaces with respect to the engagement body 63. They are therefore not optimized for good sliding properties, but rather for high static friction, for example provided with a brake lining or made from materials with appropriate properties. If a great force is exerted on the engaging body 63 by the gearwheel 60, it is strongly pressed against at least one guide surface 69, so that the engaging body 63 is prevented from moving away from the gearwheel 60 by static friction, as long as the engaging body 63 is not pulled strongly .

The two measures according to the previous two paragraphs can be used together, i.e. in addition to one another, or individually on their own.

So that the engaging body 63 cannot be pulled so hard that the static friction - be it on the teeth or on the guide surfaces 69 - can be overcome, there is an elastic member in the transmission mechanism between the handle and the engaging body 69 - in the case outlined, one compared to the previous one said spring 67, a significantly stronger compression spring 70 is provided which, when said static friction force is present and the handle is actuated, yields so very elastically that movement of the handle is not translated into movement of the engagement body 63 and thus the engagement body 63 with the toothing 66 remains engaged on gear 60.

It should be made clear that the toothing 66 does not necessarily have to be attached to a toothed wheel on the central pulley 61, but rather generally to a part which is movement-coupled with the height adjustment movement of the sit-stand table.

The appropriate high friction between the engaging body 63 and the gear 60 is achieved relatively easily by making the flanks of the toothing 66 of the gear in that area touched by the engaging body 63 very steep, i.e. completely or almost entirely at right angles to the Alignment of the tooth sequence.

So that static friction can occur at all, what for on hand of Fig. 16 described function is absolutely necessary, the following condition must apply at least at one point of the contact area of the toothing 66 of the part 60 coupled with the height adjustment movement with the engagement body 63:
The angle between the normal to the tooth flank of the movement-coupled part 60 with the height adjustment movement and the direction in which this tooth flank can in principle be moved and in which it can be driven in a height-adjustable manner by means of movement coupling with the table must be more acute (i.e. smaller) than the angle that is Arctangent of the coefficient of static friction between the two contacting material surfaces can be calculated.

In Fig. 15 is indicated as part of the transmission mechanism between the spring 57 driving the height adjustment and the lower leg parts 16 moved by this relative to the frame 47, a slide 59 which is guided on the table frame 47 in the cross member 2. The ends of those traction means 21, 22 (typically ropes), which lead to the individual leg parts 15, 16, as well as the end of that rope 62, which is deflected by the rope pulley 61 and connected to the movable end of the spring 57, are attached to the slide 59 is. Basic functions of this carriage 59 are known to achieve that with movement of the movable end of the spring 57, all those traction means 21, 22 that lead to the individual leg parts 15, 16 are moved in a synchronized manner and vice versa, that movement of an individual lower leg part 16 leads to synchronized movement of all further lower leg parts 16 and thus also the movable end of the spring 57 is moved accordingly.

According to a preferred embodiment of the invention with reference to Fig. 17 is explained in more detail, at least one engagement body 71, 72 is movably guided on the carriage 59, which is held movably guided in the cross member 2 and can be brought into engagement depending on a state of the sit-stand table with an engagement formation 73 on the cross member 2 so that it can be engaged thus the mobility of the slide 59 with respect to the cross member 2 is blocked.

The slide 59 rests on the lower surface of the cross member 2 and is guided on this in the longitudinal direction of the cross member 2 and displaceable. Two forces 74, 75, aligned opposite to one another, act on the slide 59 parallel to the longitudinal direction of the cross member. One force 74 is caused by that drive spring (using the example according to FIG Fig. 15 the spring 57) causes the intended upward movement of the table frame 47 ( Fig. 15 ) drives relative to the lower leg parts 16 remaining on the ground, or brakes the reverse movement. The second force 74 is due to the weight of the table frame 47, the table top and the load on it and is, as explained above, via traction means 21, 22 ( Fig. 15 ) and transfer these deflecting rollers to the carriage 59.

While the force 75 resulting from weight forces acts directly on the slide 59, the force resulting from the drive spring acts on one end of an arm of the engagement body 71 designed as a two-armed lever. The engagement body 71 is held indirectly on the slide 59 via a further one-armed lever 76. The engagement body 71 is thus pivotable with respect to the slide 59 both about the pivot axis of the one-armed lever 76 and also pivotable about its own pivot axis with respect to the one-armed lever 76. Both said pivot axes lie horizontally, normal to the guiding direction of the slide 59 on the cross member 2.

The knee joint formed from the one-armed lever 76 and that arm of the engaging body 71 on which the force 74 acts is pulled by the force 74 into a stretched, approximately horizontally aligned position, provided that the force 74 is the predominant effect on the knee joint. On the knee joint, however, the tensile force of a tension spring 77 acts opposite to the force 74, which is tensioned directly between the slide 59 and that arm of the engagement body 71 on which the force 74 also acts. If the tensile force of the tension spring 77 dominates over the force 74, said knee joint is strongly bent and the engaging body 71 is moved into a strongly inclined position, with that lever arm on which the spring forces act on the lower surface of the carriage 59 and the opposite lever arm on the upper surface of the cross member 2. In the example shown, this upper surface of the cross member 2 at the potential contact area with engagement body 71 is equipped with a toothing 78 running in the longitudinal direction of the cross member 2, into which one end of the engagement body 71 may engage, and thus movement of the slide 59 blocked along the cross member 2. Ideally, the tensile force of the tension spring 77, which "tries to bend" said knee joint, is significantly weaker than the force 74 originating from the drive spring and than the force 75 originating from the weight load, so that the knee joint is stretched and thus the mobility of the slide 59 is released . If, however, one of the two opposing forces 74, 75 acting from the outside on the carriage 59 fails, typically because a traction mechanism or the drive spring is broken, or the table as a whole is lifted, the tension spring 77 closing said knee joint can relax and thus intended mobility of the carriage 59 with respect to the cross member 2 - and thus also block the mobility of the lower leg parts 16 relative to the table frame.

A further engagement body 72 is held pivotably mounted on the slide 59, the pivot axis being oriented horizontally, normal to the guiding direction of the slide 59 on the cross member 2. This engagement body is also designed as a two-armed lever, but the two levers are very different in length and also very different in weight. The longer and heavier lever arm is when the sit-stand table is in the usual upright position, approximately in a horizontal position in which it is held by its weight. A tension spring acts on the second lever arm, which in the absence of other forces would pivot the engaging body 72 so that the longer lever arm would be pivoted into a steeper position, and with a tooth attached to its free end in the toothing 78 on the upper surface of the cross member 2 would snap into place.

As long as the sit-stand table is in the usual upright position, the effect of gravity on the engagement body 72 predominates so that it remains in a non-blocking position. However, if the sit-stand table is tilted or turned over or turned upside down, the effect of gravity on the position of the engaging body 72 decreases significantly and the engaging body 72 is activated by the tension spring 79 in the engaging and thus blocking movement of the carriage 59 Swiveled position. Thus, a safeguard is formed against the fact that lower leg parts extend dangerously quickly when the sit-stand table is turned over.

It should be made clear that the engagement formation 73 on the cross member 2 does not necessarily have to be a toothing. For example, it could also be a friction surface against which the engagement bodies may be pressed. For this purpose, the engagement bodies could, for example, be designed as pivotable cams or spiral bodies.

Within the scope of the invention it is entirely possible and often advantageous to provide a further drive means in addition to the spring 57, which is best placed on the slide 59 ( Fig. 15 ) acts and is also arranged in the cross member 2.

For example, this additional drive means can be an electric motor which typically drives the spindle of a spindle drive acting between the cross member 2 and the slide 59. Since a spindle drive acts self-locking against independent movement of the load, and since a maximum displacement speed is practically predetermined by the speed of the electric motor, and because the electric motor can be easily switched on and off, a great deal of security and functionality is gained. This means that the engagement bodies described above can also be omitted. Compared to a design with an electric drive and completely without an elastic spring as the drive source, a weaker and less powerful electric motor can suffice.

The additional drive means can, however, also be a gas pressure spring which acts in addition to the elastic spring between the cross member 2 and the slide 59. It is preferable to use a gas pressure spring which, in addition to providing a drive force, also offers the functions of damping movement and optionally blocking mobility. Such functions are quite common in the gas pressure springs available on the market. This also allows security and functionality to be achieved so that some or all of the engagement bodies described above can also be omitted. Compared to a construction with a gas pressure spring and without an elastic spring as the drive source, a weaker gas pressure spring is sufficient, which is more cost-effective than a stronger gas pressure spring and the resulting pushing force between the retraction and extension does not vary as much as with a stronger gas pressure spring.

Claims (23)

1. Sit-stand table the legs of which each have a lower leg part (16) and an upper leg part (15), which are designed as hollow profiles aligned in the vertical plane and which can be telescoped into one another in the vertical plane, whereby the cross-sectional area of the lower leg part (16) is encompassed by the cross-sectional area of the upper leg part (15), whereby the upper leg parts (15) are rigidly connected to a hollow, horizontally extending cross beam (2), and together with this part of an inherently rigid table frame (47), which is vertically displaceable toward the lower leg parts (16), and to which a table top (1) is fastened at the top, whereby a telescopic relative movement between a lower leg part (16) and an upper leg part (15) can be driven by a traction mechanism (21, 22), which extend into the hollows of the leg parts (15, 16) and the cross beam (2), and whereby the movement of said traction mechanism (22), which drives the lifting of the upper leg parts (15) relative to the lower leg parts (16), can be driven by a pretensioned elastic spring (57), which is arranged in the interior of the cross beam (2)
   characterised in that

   - the sit-stand table has four table legs, whereby the cross beam (2) is rigidly connected to the upper leg parts (15) via both a side beam (33) and a diagonal strut (34) respectively, whereby the side beam is directly rigidly connected to two upper leg parts (15) and the cross beam (2) respectively, whereby each diagonal strut (34) is directly rigidly connected to the upper leg part (15) and the cross beam (2) respectively, and whereby the connection of the diagonal strut (34) with the cross beam (2) is at a distance from the connection of the cross beam (2) to the side beam (33), and

   - that the connections of the upper leg part (15) with the side beam (33) and with the diagonal strut (34) are welded connections, and

   - that the traction mechanism (21, 22) runs through the diagonal strut (34), which is designed as a hollow profile.
2. Sit-stand table according to claim 1, characterised in that a lateral surface portion (37) of the upper leg part (15) covered by the front surface of the diagonal strut (34) has at least one third, preferably at least half the width of that lateral surface side of the leg part (15), of which the lateral surface portion (37) is part, protrudes without interruption to the upper lateral surface side of the side beam (33), which covers the upper front surface of the leg part (15), and that the lateral surface portion of the leg part (15) facing the side beam (33) has a lateral surface portion (39) that Is at least one third, preferably at least half as wide as this lateral surface side, and protrudes without Interruption to the upper lateral surface side of the side beam (33) and is welded thereto.
3. Sit-stand table according to claim 2, characterised in that the lateral surface portion (37) of the upper leg part (15) covered by the front surface of the diagonal strut (34) and/or the upper lateral surface portion (39) of the lateral surface side facing the side beam (33) of the leg part (15) have an opening through which a traction mechanism (21, 22) runs.
4. Sit-stand table according to one of claims 1 to 3, characterised in that the connection between the diagonal strut (34) and the cross beam (2) can be released.
5. Sit-stand table according to one of claims 1 to 4, characterised in that the connection between the cross beam (2) and the side beam (33) is a plug-in connection which is producible by a relative movement between the cross beam (2) and the side beam (33) towards each other in the longitudinal direction of the cross beam (2), and, after its production, relative movements between the two beams (2, 33) are positively locked In the directions towards each other, vertically in both directions, parallel to the longitudinal direction of the side beam (33) in both directions.
6. Sit-stand table according to one of claims 1 to 5, characterised in that in the overlapping height range between the lower leg part (16) and the upper leg part (15) of a table leg, there is an annular gap (28) which Is covered in several places by sliding coverings (29, 30), which are attached to the upper longitudinal area of the outer lateral surface of the lower leg part (16), and by further sliding coverings (31) which are attached to the lowest longitudinal area of the inner lateral surface of the upper leg part (15), whereby the sliding coverings attached to the lower leg part (16) extend at least approximately over such height range of the lower leg part (16) which is still located in the hollow enclosed by the upper leg part (15), even when the lower leg part (16) is fully extended.
7. Sit-stand table according to claim 6, characterised in that the thickness of a sliding covering (30) which is attached to the lower leg part (16) is reduced compared to its original thickness, whereby the reduction is carried out through subsequent targeted processing using a tool and so as to achieve an adaptation to the inside width of the cavity in the upper leg part (15).
8. Sit-stand table according to one of claims 1 to 7, characterised in that the axis (44) of a roller (42) which deflects a traction mechanism (21, 22) is oriented vertically and is arranged in the hollow of the diagonal strut (34), and that the running surface of the roller (42) protrudes into the hollow in the cross beam (2).
9. Sit-stand table according to one of claims 1 to 8, characterised in that a longitudinal area of an axis (44) on which a roller (42) is kept pivotable, perpendicular to the plane of a plate, by an indentation (45), which is formed through the removal of an edge surface area of the plate, protrudes through the plate and rests with part of its lateral surface on the base of the indentation (45), and that a finger (46) which forms a flank of the indentation (45) and is part of the plate, narrows the area between the axis (44) and the opening of the indentation to a width which is less than the diameter of the axis (44).
10. Sit-stand table according to one of claims 1 to 9, characterised In that the two traction mechanisms (21, 22) extending into the hollows of the leg parts (15, 16) connected there with the lower leg part (16) at a connection point (23) located in the upper area of the lower leg part (16) are deflected by three rollers (17, 18, 19), the horizontally aligned rotation axes of which are held rigidly with respect to the upper leg part (15), whereby two upper rollers (17, 18) are located on the upper longitudinal area of the upper leg part (15), and the third lower roller (19) is located in the volume enclosed by the lower leg part (16) and is held at the lower end area of a support rod (20), which is held immovably opposite the upper leg part (15), and,

    - that the axis of the lower roller (19) is held on two holding bodies (24), which together encompass the lower roller (19) in a plane lying parallel to its roller axis, and/orthat the upper rollers (17, 18) are held on two upper holding bodies (25), which together encompass the upper rollers (17, 18) in a plane lying parallel to their common roller axis.
11. Sit-stand table according to claim 10, characterised in that the two holding bodies (24, 25) in each case ile one behind the other in the axial direction of the respective rollers (17, 18, 19).
12. Sit-stand table according to claim 10 or 11, characterised in that the connection between the holding bodies (24, 25) and the support rod (20) is a plug-in connection, which is closable by relative movement of the holding bodies (24, 25) onto the end face of the support rod (20).
13. Sit-stand table according to one of claims 10 to 12, characterised in that the holding bodies (24) located on the lower end face of the support rod (20) rest on the inner surface of the lower leg part (16).
14. Sit-stand table according to one of claims 1 to 13, characterised in that the table top (1) and the cross beam (2) are blocked relative to one another against relative movement in the vertical direction and an attachment (3, 4, 5) is attached to the cross beam (2), whereby the attachment (3, 4, 5) is positively hooked to the upper area of the cross beam (2) against downward movement and In the direction of a partial lateral surface (6) of the cross beam (2), and has a contact surface (7) with which it rests on the outside of the partial lateral surface (6).
15. Sit-stand table according to one of claims 1 to 13, characterised in that relative movement between the two leg parts (15, 16) Is coupled in motion with relative movement between an interlocking (66, 78) body (66, 2) and a guided, movable engagement body (63, 71, 72), whereby the engagement body (63, 71, 72) can be brought into and out of engagement with the interlock (66, 78) through its guided mobility, whereby the relative movement is blocked in the event of engagement, whereby the engagement body (63, 71, 72) dependent on the state of the sit-stand table can be brought into a state in which it automatically engages, and/or Is fixed in the engaging position.
16. Sit-stand table according to claim 15, characterised in that the interlock (66) is located on a gearwheel (60), which is connected to a roller (61) which deflects a traction mechanism (62).
17. Sit-stand table according to claim 15 or 16, characterised in that the state of the sit-stand table is that force with which the interlock (66) rests on the engagement body (63).
18. Sit-stand table according to claim 15 or 16, characterised in that the state of the sit-stand table is its angular alignment with respect to the gravitational force, that the engagement body (72) is movable through both gravitational force and through the effect of a gravitation-independent drive source (79), whereby the gravitational force and the gravitation-independent drive source (79) on the engagement body (72) act in opposite directions, and the direction of the induced possible movement of the engagement body (72) caused by the gravitation-independent drive source (79) is that which transfers It into the position of engagement with the interlock (78).
19. Sit-stand table according to claim 15 or 16, characterised in that the state of the sit-stand table is the tensile stress of a traction mechanism, which is intended to pair the movement of the movable end of the spring (57) with a lifting or lowering movement of the table frame (47).
20. Sit-stand table according to one of claims 1 to 14, characterised in that, in addition to the elastic spring (57), another drive motor is arranged in the hollow of the cross beam (2), which is also set up to drive the movement of that traction mechanism (22), through the movement of which the lifting movement of the table frame (47) can be driven.
21. Sit-stand table according to claim 20, characterised in that the further drive motor is effectively arranged to act between the cross beam (2) and a slide (59), the slide (59) being held in the cross beam (2) so as to be longitudinaliy displaceable and is motion-coupled with those traction mechanisms (21, 22) which extend into the leg parts (15, 16).
22. Sit-stand table according to claim 20 or 21, characterised in that the further drive motor is an electric motor.
23. Sit-stand table according to claim 20 or 21 , characterised in that the further drive motor is a gas pressure spring.

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