WO1997038239A1

WO1997038239A1 - Table construction

Info

Publication number: WO1997038239A1
Application number: PCT/SE1997/000586
Authority: WO
Inventors: Alf Claesson
Original assignee: Kinnarps Ab
Priority date: 1996-04-09
Filing date: 1997-04-08
Publication date: 1997-10-16
Also published as: AU2418297A

Abstract

The invention relates to a table construction having a bottom stand section (32) capable of supporting against an underlying surface (A), a top stand section (33) which coacts with the bottom stand section and which is adapted to carry a table top (31), and a weight-balancing, stand-related arrangement. The construction includes at least one resilient means (42) which when raising or lowering the top stand section (33) and the table top (31) functions to change the force required in this respect, wherein the resilient means is included in a hydraulic/pneumatic coupling arrangement. At least two resilient means (42, 42a) are mounted parallel with one another and each resilient means includes a floating piston which separates a pneumatic space in respective resilient means from a hydraulic space which is common to the resilient means. The desired change in the force required is achieved by increasing or decreasing the pressure in the hydraulic space.

Description

TITLE OF INVENTION: TABLE CONSTRUCTION

FIELD OF INVENTION

The present invention relates to a table construction and then more particularly, but not exclusively, to a table con¬ struction that includes a bottom stand section that supports against an underlying support surface, a top stand section that coacts with the bottom stand section and adapted to support a table top, and a stand-related weight-balancing arrangement.

The invention also relates to such table constructions with which the configuration of the bottom stand section is rela¬ ted to the configuration of the top stand section, whereby said sections are mutually adapted to enable the top stand section to be raised and lowered in relation to the bottom stand section.

The table construction includes an activatable/deactivatable latching device which can be brought to a latching position in which the stand sections are latched in their set posi¬ tions of adjustment, said latching position being adapted to enable loads acting on the table top, among other things, to be absorbed without needing to change the position of adjustment between the stand sections and the vertical height of the table top to any appreciable extent.

The latching device is also designed to be able to take an inactive position in each selected position of adjustment between the stand sections, so as to enable the table top to be raised or lowered together with the upper stand section from a preceding selected position of adjustment, or setting, to a new setting position. The table construction also includes resilient and/or height regulating devices or spring means functioning to change or alter the force required to raise or lower the upper stand section and the table top, said resilient means, or spring means, being included in an hydraulic/pneumatic coupling arrangement.

The inventive table construction is primarily intended for use as a work table and the resilient means used are adapted to take-up loads acting on the table top without said loads and the forces generated thereby causing a change in the relative position of adjustment between the stand sections.

DESCRIPTION OF THE BACKGROUND ART

Several different designs of table constructions of the aforedefined kind are known in the art.

For instance, known in the art are table constructions that have crossed leg parts that extend between the bottom stand section and the top stand section of a stand arrangement.

It is also known to use in such table constructions one or more resilient means that are compressed or expanded in response to vertical movement of the table top, for the purpose of equalizing and/or balancing weight.

It is also known to use one or more gas spring arrangements in this latter respect.

As an example of the present standpoint of techniques, refe¬ rence is made to the disclosures of U.S. Patent Publication US-A 4,558,648.

This publication teaches a table construction with which a bottom stand section and a top stand section are mutually connected through the medium of scissor-like or mutually intersecting leg parts, and which includes a gas spring arrangement for relieving otherwise occurring forces and for raising or lowering a table top.

The publication discloses the possibility of storing in a compressed gas the energy that is recovered when lowering a table top and from the forces generated by articles resting thereon and similar forces, and of utilizing this energy to assist in raising the table top and the articles resting thereon from a lower position to an upper position, with the addition of a small force.

Also known are stand, or frame, constructions that have vertically extending and mutually parallel telescopic leg assemblies by means of which a stand top can be raised and lowered to different vertical positions.

It is also known to move the top surface of a stand con¬ struction to a desired working height by manually manipu¬ lating the stand construction in different ways.

By way of an example of the present standpoints of techni- que, reference is made to Applicant's own International Patent Application PCT/SE95/01119, Publication No. WO 96/10935.

With regard to the features particular to the present mven- tion, it can be mentioned that Patent Publication DE-18 02 193 discloses an hydro-pneumatic gas spring which is parti¬ cularly designed for supporting and adjusting hospital beds, wherewith two piston-cylinder devices are coordinated so that their respective pistons act m a pressurized fluid such as to separate two communicating gas-filled spaces, one in each cylinder, with the aid of two floating pistons (12, 35 ) .

Patent Publication PCT/GB94/00557 describes and illustrates an hydro-pneumatic resilient means for use with chairs, wherein the piston-cylinder device has a piston which works in a fluid, such as liquid, by means of which a cooling piston (61) separates a pneumatic space (21) . Selected pressure is generated in a pressure generating unit (30) .

Patent Publication US-A 3,847,410 describes and illustrates a levelling system for absorbing shocks in vehicles, wherein the system includes at least one cylinder connected to one end of the vehicle, a valve piston reciprocatingly movable in a cylinder, a piston rod connected to the piston and extending from one end of the cylinder and adapted for coaction with the other end of the vehicle.

A quantity of damping fluid in the cylinder is used to dam¬ pen the reciprocating movement of the piston and define a gas chamber which includes a gas quantity.

A floating piston is also used in this case to separate the gas volume from the liquid, and means are provided for varying the gas pressure and thereby control damping.

A piston (32) also acts against a liquid filled space (14] in this case.

SUMMARY OF THE PRESENT INVENTION

TECHNICAL PROBLEMS

When considering the technical deliberations which one of normal skill in this art must undertake in order to find a solution to one or more technical problems, involving on the one hand realization of those measures and/or sequence of measures that must be undertaken and, on the other hand, the selection of the means or those means required to put these measures into effect, it will be seen that the following technical problems are highly relevant in the development of the present invention.

When considering the present standpoint of techniques as described above, it will be evident that a technical problem resides in providing a two-stand table construction in which the bottom stand section and the top stand section are able to move vertically in relation to one another so that the table top, or work top, will move truly horizontally when raised and lowered, essentially irrespective of the total instantaneous load thereon, such as loads of at least 100 kg, and selected instantaneous load distribution.

In the case of a table construction of the kind described in the introduction, it will also be seen that a technical problem is one of realizing the significance of and the advantages afforded by using at least two resilient means that are included in an hydraulic-pneumatic coupling arrangement.

It will also be seen that a technical problem is one of realizing the significance of and the advantages afforded by using at least two mutually parallel resilient means, each coacting with a respective supporting leg of the table con¬ struction, wherewith each resilient means shall include a floating piston which separates a pneumatic space in respec- tive resilient means from an hydraulic space that is common to both resilient means.

Another technical problem is one of realizing the signifi¬ cance of and the advantages afforded by enabling the requi- red force to be changed by increasing or decreasing the pressure in the hydraulic space and transmitting this pressure to the pneumatic spaces via floating pistons.

Another technical problem is one of realizing the signifi¬ cance of and the advantages that are afforded the top stand section and the bottom stand section coact mutually through an array or arrangement of mutually coordinated telescopic parts with a pneumatic piston-cylinder device allocated to each array.

With regard to a table construction of the kind defined in the introduction, it will be seen that a technical problem is one of creating conditions with the aid of simple means whereby the common hydraulic space will be orientated between the arrays of mutually-coordinated telescopic parts.

It will also be seen that a technical problem is one of realizing the significance of and the advantages associated with providing a pressure source which generates an over¬ pressure and which is adapted to the top stand section and connected to the common hydraulic space.

With the intention of obtaining true parallelism in respect of movement of the table top in relation to the coordinated telescopic parts, there is used a horizontally extending and axially rotatable rod, or bar, which is arranged between said arrays of coordinated parts in a manner to guide said parallel movement of the table top.

A further technical problem is one of realizing the advan- tage of providing one end of the rod with a gearwheel, or pinion wheel, that coacts with one or more toothed racks belonging to said component arrays.

Another technical problem is one of realizing the signifi- cance of and the advantages afforded by mounting the rod on the centrally positioned telescopic part for rotation in relation to said part.

Another technical problem is one of realizing the signifi¬ cance of and the advantages afforded by positioning a toothed rack in relation to the outermost telescopic part, and by providing a toothed rack in relation to the innermost telescopic part, with a gearwheel, or pinion wheel, coacting with both racks.

It will also be seen that a technical problem is one of realizing the significance of adapting the latching device for coaction with the rotatable rod such as to latch the rod against rotation or to allow the rod to rotate.

Another technical problem is one of realizing the signifi¬ cance of arranging respective floating pistons in a horizon¬ tal tubular member belonging to the piston-cylinder arrange¬ ment and located beneath the table top.

In the case of a table construction of the kind defined in the introduction, a technical problem resides in the use of an arrangement for regulating the spring force generated by a spring arrangement in which the resilient means, a gas spring, used is included in a weight-balanced stand arrange- ment, wherein the gas spring includes a cylinder part which delimits an inner, pressurized space, and a piston which can be displaced relative to the cylinder part, wherein the piston part can be moved into the cylinder part with an increasing force, wherein the requisite force increase is contingent on the extent to which the piston part is in¬ serted into the cylinder part and corresponds to the increasing gas pressure in said space and/or vice versa.

Another technical problem is one of realizing the signifi- cance of those conditions required to achieve desired adjustment of the pressure and of the pressure force by causing the inner space of the cylinder part to communicate with an hydraulic controllable pressure source, via a floating piston.

Another technical problem is one of realizing the advantages that are obtained when causing a piston-cylinder device to coact pneumatically with a gas spring, whereby the initial pressure of the gas spring is controllable.

Another technical problem is one of realizing the advantages that are afforded when the pneumatic pressure to be genera¬ ted by the piston-cylinder device can be selected and regu¬ lated through the medium of simple control means.

Another technical problem resides in realizing the signifi¬ cance of the ability to use a.pressure source in the form of a pneumatic/hydraulic piston-cylinder device wherewith the pneumatic pressure in first cylinder-delimited spaces can be regulated in dependence on the hydraulic pressure acting within a second cylinder-delimited space, this latter space communicating with an hydraulic pressure source, and there¬ with be able to adjust the position of the piston in the cylinder and/or movement of the piston therein.

A further technical problem is one of realizing the signifi¬ cance of providing an aperture at that end of the cylinder- part of the gas spring that lies distal from the piston and the piston rod and by providing an aperture at that end of the pneumatic cylinder-part of the piston-cylinder device which lies distal from the piston, such that said two apertures are able to communicate freely with each other through the medium of a passageway and therewith mutually connect at least two cylinder-related pneumatic spaces.

In the case of this latter application, a further technical problem resides in realizing the simplifications that can be achieved and the advantages that are afforded when a piston- cylinder device is divided so that a pneumatic pressure will act on one side of a floating piston and an hydraulic (oil) pressure will act on the other side of said piston, said piston being located in one and the same cylinder-part.

Another technical problem is one of realizing the construc¬ tive advantages that are associated with positioning the cylinder-part of the gas spring vertically, while positi- oning the hydraulic piston-cylinder device horizontally.

Another technical problem is one of providing a simple con¬ struction which enables the generated pressure force to be regulated, such as increased, by virtue of increasing the hydraulic pressure delivered by the pressure source propor¬ tionally or functionally in response to an increase in the extent to which the piston is inserted into the cylinder or vice versa.

In the case of a weight-balanced stand arrangement, a tech¬ nical problem resides in the ability to utilize a pneuma¬ tic/hydraulic spring arrangement that has an adjustable spring force, and therewith provide simple conditions for enabling the hydraulic pressure to be adjusted and set so as to generate a selected spring force.

SOLUTION

With the intention of solving one or more of the aforesaid technical problems, the present invention takes as its starting point a table construction of the kind defined in the introduction.

It is particularly proposed in accordance with the invention that two resilient means are arranged in parallel, and that each resilient means shall include a floating piston which separates a respective pneumatic space in each of the resi¬ lient means from an hydraulic space which is common to both of the resilient means, and that the requisite pressure force is changed by a controlled increase or controlled decrease of the pressure in the hydraulic space.

In accordance with proposed embodiments that lie within the scope of the inventive concept coaction between the top stand section and the bottom stand section is effected through the medium of telescopically related and mutually coordinated parts that form a respective component array, and a pneumatic piston-cylinder device or arrangement is provided for each such component array.

The common hydraulic pressure is generated in a space located between said component arrays.

According to the invention, an hydraulic pressure source which generates an overpressure, or positive pressure, is adapted to a top stand section and connected to the hydraulic space.

Movement of the table top in parallelism is made possible by an axially rotatable rod that extends between said component arrays for coaction therewith.

The rotatable rod carries at its ends a pinion wheel which coacts with a respective toothed rack that forms part of said component array.

The rod is fixed to and rotatable in relation to the central telescopic part.

According to one embodiment, a toothed rack is related to the outermost telescopic part, and a toothed rack is related to the innermost telescopic part with said gear wheel, or pinion wheel, coacting with both racks.

The inventive table construction also includes a latching device which is adapted for coaction with the rotatable rod and functions to latch the rod against rotation or to allow the rod to rotate.

A respective floating piston is provided in a tubular member forming part of the piston-cylinder device and located beneath the table top.

The invention also includes an arrangement for regulating the spring force generated by a spring arrangement, wherein the spring force can be controlled at one and the same position of insertion or retraction of the gas spring piston into the cylinder-part, by virtue of the interior of the pneumatic cylinder-part being connected, via a floating piston, with a controllable hydraulic pressure source.

The hydraulic pressure source may comprise a piston-cylinder device where the pneumatic pressure in said space can be adjusted in dependence on the position of the piston in said cylinder.

The cylinder of the gas spring is provided with an aperture or a hole at the end thereof remote from the piston, and the cylinder the piston-cylinder device is provided with an aperture or a hole at the end thereof remote from the piston, wherein the arrangement includes a passageway by means of which the two apertures communicate pneumatically with one another.

The pressure from the hydraulic pressure source is caused to increase or decrease in correspondence to the extent to which the piston is inserted into or extended from the cylinder, so as to adjust said force. ADVANTAGES

Those advantages primarily afforded by an inventive table construction reside in the provision of conditions whereby the table top can be raised and lowered in true parallelism with the aid of at least two separate pneumatic piston- cylinder devices whose cylinders house floating pistons which separate the pneumatic spaces around the pistons from a common adjacent hydraulic space whose pressure can be regulated to raise or lower the vertical position of the table top and to take-up different weights on the table top.

The main characteristic features of an inventive table construction are set forth in the characterizing clause of the following Claim 1.

BRIEF DESCRIPTION OF THE FIGURES

The invention will now be described in more detail with reference to a number of exemplifying embodiments thereof having features significant of the present invention, and with reference to the accompanying drawings, in which

Fig. 1 illustrates the principle construction of a known gas spring and the increasing force variation generated by the insertion of a piston into a cylinder;

Fig. 2 is a side view, partially sectioned, of a gas spring which is connected pneumatically to a pneumatic/hydraulic piston-cylinder device; Fig. 3 is a perspective view of a stand arrangement for a table construction, the table top being omitted for the sake of clarity;

Fig. 4 is a sectional view of two resilient means that utilize one and the same hydraulic space;

Fig. 5 is a cross-sectional view of a supportive leg according to Fig. 3 positioned on the left of the

Figure;

Fig. 6 is a side view of the left support leg in Fig. 3 and shows the leg in a fully extended state;

Fig. 7 illustrates alternative coaction between two resilient means; and

Fig. 8 illustrates a manual variant of the embodiment shown in Fig. 7.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Fig. 1 is a simplified illustration of a first gas spring 1 having a cylinder 2 which delimits an inner pressurized space 2', and a piston 3 which is movable relative to the cylinder 2. Insertion of the piston into the cylinder can be effected with an increasing force F, this increase in the force required being dependent on the extent to which the piston is inserted into the cylinder, therewith resulting in a higher or lower gas pressure in the space 2.

The left side of Fig. 1 shows the piston 3 of the gas spring 1 fully extended from the cylinder 2.

Shown on the right of Fig. 1 is a second gas spring la whose piston 3a is fully inserted into the space 2a' in the cylinder 2a.

At a chosen initial overpressure P in the space 2 ' , a force FI is required to initially press the piston 3 into the cylinder 2, and as the extent "a" to which the piston is inserted increases the overpressure in the space 2' (2a') will also increase and will require a maximum force F2 to fully insert the piston 3a into the cylinder 2a' .

It is also known that when the space 2' has a high initial overpressure P, so as to require a force FI' to achieve initial movement of the piston 3 into the cylinder 2, a greater force F2' will be required to fully insert the piston 3a into the cylinder 2a.

The gas spring arrangement 1, la is normally more complex than the principally illustrated arrangement, and will include a completely closed and pressurized space or chamber 2' in the cylinder 2.

Fig. 2 illustrates an inventive arrangement that includes a gas spring 1 having a cylinder 2 and a piston 3.

Provided in the upper part of the cylinder 2 is a hole 2c which connects with a channel 4 which, in turn, connects with a pressure source 5.

The pressure source 5 may be of a conventional kind and will be described in more detail hereinafter.

In accordance with the invention, the pressure source 5 can be operated so as to enable any pressure P in the space 2' to be selected within practical ranges.

Thus, the initial force FI may be any force selected between the limit values FI and FI' in Fig. 1, while the terminating spring force F2 and F2' may be selected between different values.

It also lies within the scope of the invention to sense the extent to which the piston 3 and the piston 3a are inserted into respective cylinders, with the aid of a position indi¬ cator 6, and to control and regulate the pressure in the line 4 from the pressure source 5 so as to obtain an adapted force variation during movement of the piston.

Fig. 1 is intended to show that at an initial force FI, the pressure source 5 can be caused to increase the pressure P in the line 4 and therewith also in the space 2', wherewith a force change will increasingly follow the curve or graph 20, or vice versa.

Alternatively, the pressure source 5 may, of course, be dependent on the position of the piston 3, 3a in respective cylinders and to produce a reducing pressure in the line 4, and therewith the space 2', so that the force change will follow the curve or graph 20' in Fig. 1 decreasingly, or vice versa.

For the sake of simplicity, the following description will, in principle, be limited solely to the embodiment in which the pressure source 5 is set to one value from among several possible values.

Fig. 2 is a side view and partially sectioned view of a gas spring arrangement 1 having a cylinder 2 which houses a piston 3. The piston 3 connects pneumatically with an adja¬ cent piston-cylinder device 3 through the medium of a con¬ necting piece 10 that includes a channel 4. The piston 3 delimits an upper and a lower space which communicate pneumatically with each other. The gas spring unit is shown in a state in which the piston rod 3b is extended to a substantial extent and a non-sealing piston 3 in a lower position.

A pneumatic cylinder-part or space 2' can be placed under different initial pressures by the piston-cylinder device 50, therewith enabling different forces FI to be chosen for one and the same piston position during movement.

The piston-cylinder device 50 has a first, an upper pneumat¬ ic, space 51, and a second, a lower, hydraulic space 52.

A "floating piston" 53 is adapted to sealingly separate the upper pneumatic cylinder space 51 from the lower hydraulic cylinder space 52. This latter space 52 connects with an hydraulic pressure source 5 via a channel 54.

In the illustrated case, the pressure source 5 is comprised of a hand-operated hydraulic pump of known construction, although it may alternatively comprise a motor-driven hydraulic pump.

Thus, the channel 54 connects hydraulically with a pump 55 which is operated by means of a lever 55a (a hand-operated or foot-operated lever) and pumps hydraulic oil under pres¬ sure to the space 52, therewith raising and pressing the "floating piston" 53 upwards against an increasing pneumatic pressure in the space 51, so as to create conditions for an increasing force FI via the channel 4 to the space 2'.

If the pressure in the space 51 is excessively high, the pressure can be reduced by allowing hydraulic oil to pass down into a sump 55c, via a valve 55b.

When the lever 55a is hand-operated, the lever will conve- niently be located in the vicinity of the table top, or work top, and at the base of the stand construction when foot- operated.

Fig. 3 is a perspective view of a table construction 30, in which the table top 31 has been omitted for the sake of clarity. The table construction 30 includes a bottom stand section 32 which is shown supported on a supporting surface A, a top stand section 33 which coacts with the bottom stand section 32 and which is adapted to carry the table top 31 and a weight-balancing stand-related arrangement.

A first weight-balancing arrangement is built-in the left support leg in Fig. 3, and a second weight-balancing arrangement is built-in the right support leg 40a in Fig. 3.

Since the weight-balancing arrangements 40, 40a are mutually identical, the following description refers mainly to the arrangement 40.

Fig. 3 shows schematically that the bottom stand section 32 has a form related to the top stand section 33, so that said sections will enable the top stand section 33 to be raised or lowered in parallelism and in relation to the bottom stand section 32.

The arrangement includes an activatable/deactivatable latching device by means of which the stand sections can be locked in each selected setting position and adapted to take-up loads acting on the table top 31 without changing the position of adjustment between the stand sections 32, 33 and the vertical height of the table top 31.

The latching device shall be able to take a latch release position at each chosen position of adjustment between the stand sections, such as to enable the table top to be raised and lowered and to move the stand section from a chosen position to a new position.

The arrangement includes at least one resilient means which enables changes to be made in the force required to raise and lower the upper stand section and the table top, said resilient means forming part of an hydraulic/pneumatic coupling arrangement.

Fig. 4 illustrates an embodiment in which at least two resi¬ lient means 42, 42a are arranged parallel to one another and where each resilient means 42 includes an angled pneumatic space 43 comprising a combination of the spaces 43a, 43b. A piston is able to move into and out of the space 43a.

The space 43b and a corresponding space 44b are coordinated in a horizontal pipe 45 and respective floating pistons 46 and 46a are disposed in the pipe 45 and separate the two pneumatic spaces 43b and 44b from an intermediate hydraulic space 47.

The pressure in the space 47 is regulated via an hydraulic pump device 5 connected to an inlet opening 47a.

With respect to the table support leg 40 coaction between the top stand section 33 and the bottom stand section 32 is effected through the medium of a number of mutually Telescopic parts 49a, 49b, 49c that are coordinated in a component array. A pneumatic-cylinder device 1 is mcorpo- rated in said telescopic parts in a manner shown more clearly in Fig. 5.

An overpressure generating pressure source 5 is adapted to the top stand section 33 and connected to the hydraulic space 47. A rod 60 that can be rotated about its own axis extends between the component arrays 40, 40a to enable parallel displacement of said arrays.

The rod 60 carries on each end a gear wheel 61 adapted for coaction with at least one toothed rack in said component array.

A first rack is referenced 62 and a second rack is referenced 62a.

The first rack 62 supports against the underlying support surface A, whereas the second rack 62a is attached to the inner part 49c with the piston-cylinder device 1 mounted within said inner part 49c.

The telescopic movement between the parts 49a, 49b and 49c respectively is guided by a number of wheels 63.

The rod 60 is attached to and rotatable in relation with the centre telescopically-related part 49b, via bearing means 60a.

As before mentioned, one toothed rack 62 is related to the outermost telescopic part 49a and one toothed rack 62a is related to the innermost telescopic part 49c, with the gear wheel 61 coacting with both racks.

A latching device 60b coacts with the rod 60 to lock the rod against rotary movement and to release the rod for rotation.

Fig. 6 illustrates schematically the telescopic parts 49a, 49b and 49c extended to a maximum. The toothed wheel 61 has lifted the rack 62a to its maximum raised position, with the gear wheel 61 moving along the rack 62 to its upper position. This construction requires the outer telescopic part 49a to be provided with a slot 49a' along which the rod 60 is able to pass as the telescopic part 49b lifts in relation to the telescopic part 49a.

Fig. 7 illustrates an alternative embodiment in which one single floating piston 46' is used in a cylinder 70 whose lower space 71 is filled with fluid and which can be pressu- rized via a pump 72 and a pressure regulating means (not shown) .

The piston 46' delimits a pneumatic space 73 which communi¬ cates with a pneumatic piston-cylinder arrangement including the parts 40 and 40a, via pipes 74, 74a.

Pneumatic spring arrangements of this kind include a through-passing channel or channels for the piston, so that the same pressure will prevail on both sides of the piston in the cylinder.

Fig. 8 shows a piston-cylinder arrangement in which the pressure in the space 73 can be regulated by means of a knob 80, said space 73 forwarding this pressure to the pipes 74, 74a in a known manner.

It will be understood that the invention is not restricted to the aforedescribed and illustrated exemplifying embodi¬ ment thereof and that modifications can be made within the scope of the inventive concept as defined in the following Claims.

Claims

1. A table construction having a bottom stand section that can be supported against an underlying surface, a top stand section which coacts with the bottom stand section and which is adapted to carry a table top, and a weight-balancing stand-related arrangement, wherein the bottom stand section has a form related to the top stand section such as to adapt said sections for raising and lowering the upper stand sec- tion in relation to the bottom stand section, wherein the table construction further includes an activatable and de- activatable latching device which can take a locked position at each chosen position of adjustment between the stand sec¬ tions and which is capable of taking-up loads acting on the table top, among other things, without any appreciable change in the position of adjustment between the stand sec¬ tions and the height position of the table top, wherein the latching means can also take a release position at each chosen position of adjustment between the stand sections so as to enable the table top and the top stand section to be raised or lowered from the chosen position of adjustment to a new position of adjustment, and further includes at least one resilient means which when raising or lowering the top stand section and table top is able to change the force re- quired herefore, said resilient means being included in an hydraulic/pneumatic coupling arrangement, characterized in that at least two resilient means are arranged parallel to one another; in that each resilient means includes a floa¬ ting piston which separates a pneumatic space in respective resilient means from an hydraulic space which is common to said resilient means; and in that said change in said requ¬ ired force is effected through an increase or a decrease in the pressure in the hydraulic space.

2. A construction according to Claim 1, characterized in that coaction between the top stand section and the bottom stand section is effected through the medium of a number of telescopically related parts that are coordinated to form a component array, wherein each array of coordinated compo¬ nents coacts with a pneumatic piston-cylinder device.

3. A construction according to Claim 1 or 2, characterized in that the common hydraulic space is located between said component arrays.

4. A construction according to Claim 3, characterized by an overpressure generating pressure-source adapted to the top stand section and connected to the hydraulic space.

5. A construction according to Claim 1 or 2, characterized by a rod located between said component arrays and function¬ ing to guide said arrays for parallel movement.

6. A construction according to Claim 5, characterized in that the rod carries at its ends gear wheels for coaction with a respective toothed rack included in said component array.

7. A construction according to Claim 2 or 5, characterized in that the rod is attached to and rotatable in relation to the centre telescopic part.

8. A construction according to Claim 6 or 7, characterized in that a toothed rack is related to the outermost tele¬ scopically related part; in that a toothed rack is related to the innermost telescopically related part, with the gear wheel coacting between the two racks.

9. A construction according to Claim 1 or 6, characterized in that the latching device is adapted for coaction with the rod such as to latch said rod against rotary movement or to release said rod.

10. A construction according to Claim 1, characterized in that respective floating pistons are disposed in a tubular member forming part of said piston-cylinder devices and located beneath the table top.

11. An arrangement for regulating a spring force generated by a spring arrangement, wherein the spring arrangement in¬ cludes a spring element in the form of a gas spring, inclu- ded in a weight-balanced stand structure, preferably inclu¬ ded in a table construction according to any one of the pre¬ ceding Claims, wherein the gas spring includes a cylinder adapted to delimit an inner pressurized space, and a piston adapted for movement relative to said cylinder, wherein insertion of the piston into the cylinder can be achieved with an increasing force, and wherein a requisite force in¬ crease is contingent on the increase in gas pressure caused in the cylinder space as a result of the insertion of the piston thereinto and/or vice versa, characterized in that the force can be adjusted at one and the same position of piston insertion into the cylinder by virtue of the inner space of the pneumatic cylinder communicating with an hyd¬ raulic pressure source via a floating piston, the pressure of said source being controllable.

12. An arrangement according to Claim 11, characterized in that the hydraulic pressure source is comprised, inter alia, of a piston-cylinder device, wherein the pneumatic pressure in said space can be adjusted in dependence on the position of the piston in the cylinder or the hydraulic pressure source.

13. An arrangement according to Claim 11 or 12, character¬ ized in that the gas spring cylinder is provided with an aperture or a hole at one end thereof remote from the pis¬ ton; in that the cylinder of the piston-cylinder arrangement is provided with an aperture or a hole at one end thereof remote from the piston; and in that the two apertures commu¬ nicate pneumatically with each other.

14. An arrangement according^' to Claim 11 or 13, character¬ ized in that the gas spring cylinder is positioned adjacent the cylinder of a pneumatic/hydraulic piston-cylinder device.

15. An arrangement according to Claim 11, characterized in that the force is adjustable by virtue of the ability of the pressure generated by the hydraulic pressure source to in¬ crease or decrease in respect of an increasing extent of piston insertion into the cylinder and vice versa.

16. An arrangement according to Claim 11 or 12, character¬ ized in that the piston-cylinder device is divided so that pneumatic pressure will act on one side of a "floating pis¬ ton" and an hydraulic pressure will act on the other side of said piston.

17. An arrangement according to Claim 1 or 11, character¬ ized by an hydraulic pump connected to said piston-cylinder device for increasing or decreasing the hydraulic pressure within an hydraulic space in respect of said piston-cylinder device.