SI20927A - Telescopic foldable stand - Google Patents

Abstract

The aim of the invention is to provide a concept of a telescopic foldable stand made up from staircase elements (1) with a corresponding operating drive. The stand should be suitable particularly for indoor facilities and should on one side provide the possibility of making available the largest possible ground plan surface after assembly and requiring a minimum ground plan surface for storage. The stand should also be mobile at least as much as to enable shifting it around the facility. At the same time the stand should be suitable to accept a larger number of spectators as well as transferring loads arising this way, onto the surface, which is in such facilities mostly provided as a relatively soft or elastic surface, usually available in sporting facilities for performing sport activities. According to the invention the stand consists of a corresponding number of staircase elements (1), which can be positioned one on top of the other or which can be drawn one beneath the other. Each element on the lateral side of the stand features at least one supporting assembly (2) consisting of a non-removable supporting unit (21) and a moving supporting device (220). The moving of staircase elements (1) is carried out with the help of a rope (32), which is wound to a motor driven winding reel (31), located in the area of the last part of the stand, running actually along its whole length.

Description

The present invention deals with a trumpet that is telescopically foldable, namely, foldable and also disassembled; this platform is intended for spectators and other visitors to sports and other events, especially in covered event facilities such as multi-purpose school lounges, gyms and other sports or event halls.

The invention is based on the problem of designing a telescopically folding stand, particularly suitable for covered event facilities, which, on the one hand, are intended to be compatible with the largest floor area or surface. dismountable to a minimum storage capacity, it should be mobile and moveable at the same time and at the same time be suitable for receiving large numbers of viewers and for carrying the related loads, which is intended in particular for the uniform carrying of these loads to a substrate which may generally be a relatively soft or elastic substrate such as e.g. available for use in sports facilities, without pitching the stands.

EP-566 017 discloses a telescopically folding stand consisting of a number of step-shaped segments which can either be folded under one another or pulled out from under one another in a direction parallel to the substrate. These segments are mounted in horizontally extending guides. The guides are either mounted in the base or attached to the base, but in each case they are interfering and may interfere with the implementation of e.g. sports activities right next to the stands, and in some cases may even pose a certain danger. In addition, the possibility of wedging individual segments in the guides is not excluded, especially if the length of the stand is significantly greater than its depth or. floor plans. The Applicant assumes that the segments are manually drawable, which means that assembling the panel, ie pulling the segments from one another under the other, as well as disassembling the panel, ie placing the segments under one another, is a difficult task. Based on the above it is obvious that the most suitable solution for implementing small tribune for the adoption of a small number of viewers, which ⁷ is actually in contradiction with the need for a relatively unfavorable and complex installation guides in or on the ground.

Also known from WO 94/25706 is a telescopically folding stand, which again consists of a number of stepwise-designed segments that can either be driven one below the other or taken in parallel with the substrate. These segments are provided with wheels or similar rolling elements. The solution is a bit more demanding and also more expensive, so it is economical especially when it is possible to count with a larger capacity stand. In this case, assembling or disassembling the stands is much easier, but the disadvantage of the solution under consideration is that the load on the substrate is much higher in such a solution, and especially the less favorable transfer of these loads to the substrate. The grounds in the event facilities, especially in the facilities for performing sports activities, are basically tailored to the needs of performing these activities. Often these are parquet, plastic or even specially designed resilient floors, and all of these substrates are very sensitive to locally concentrated loads. Therefore, it is difficult or impossible to avoid damaging the substrate in this solution.

Telescopic folding of this kind of stand can be ensured by means of a rope or similar traction element and appropriate means. It is possible to provide an electromotor driven drum and to wind or reel it. unbind it from segment to segment on one side of the grandstand and then on the other side of the grandstand. As each rope is fairly elastic, when tightening the rope, the rope part on the one side fastens the segments and the rest on the other side is looser. This causes the stands to rotate and become stuck. The drum actuator can be installed on both sides of the grandstand, which requires the use of two motors, the operation of which must be perfectly coordinated, which again dictates the need to fit a complex steering assembly. On top of that, even in this case, it is not necessary that there will be no differences in the tension of the rope over one and the other ends of the stand over time, which, even with the perfectly coordinated operation of the two engines, inevitably leads to problems.

WO 98/02628 (PCT / GB97 / 01931) refers to a combined stair lift, a kind of platform that is telescopically foldable and disassembled, meaning that it consists of a series of stair segments, generally of equal or at least about the same width and depth, whose height is so adjusted that the assemblies are horizontally adjustable under one another or. pullable under one another. The staircase segments, together with the drive means, are housed in the housing. Drawing out stair segments, which means assembling a grandstand. the stairs, as well as the disassembly, is done in synchronization with the help of a chain-link, thanks to the clamped chain wheels through which the chain is routed. The chain is terminated by two running arms, with pulls for one arm causing the segments of the other to be pulled out from the other, and pulling for the remaining arm of the chain results in the movement of the segments one below the other. On top of that, the grandstand is equipped with an elevator, a kind of a lifting platform, located directly at the bottom or. the lowest stair segment, so that the latter can be installed even through this platform when using the compound platform. A particular problem is posed by propellants, in particular e.g. electric motor, gearbox, etc.) to be installed outside the floor plan, usually at the rear. This means that the stand must in any case be spaced from the wall for a certain distance, which means irrational use of very valuable space in such objects. Apart from this, this kind of stand is demountable, but together with the enclosure, it is essentially stationary. unsuitable for moving around the gym or other terrain. The hull itself, together with the supporting skeleton, chain wheels, relatively long chain and propellants, represents the great weight of the stand in unladen condition. Even if the platform below were fitted with wheels, moving such a wheel in an unladen condition could result in damage to the base. As mentioned in the analysis of the prior art solutions, there is usually a floor available in sports facilities that is appropriate for performing sports activities, eg. for parquet flooring, various plastics, floor coverings, or even specially designed elastic wooden floors. Furthermore, it is obvious that a loaded stand, when full of spectators, presents an even greater load on the ground. Fortunately, the stand, according to WO 98/02628 (PCT / GB97 / 01931), is not suitable for larger widths and thus for the reception of a very large number of spectators, since the design of the unilateral drive allows for the uneven movement of both sides of the stair segments and therefore the wedges thereof, if they were extremely wide or. long.

The solution to the problem posed is a telescopically folding stand, which generally consists of an appropriate number of second-to-install and / or adjustable stands. the other below the other drawable stair segments which are movable by means of a drive train, in particular by winding a rope or similar flexible traction element on a winding drum or. unwinding the rope from there, said drum being driven by a suitable motor, in particular an electric motor. According to the invention, each of the stair segments of the telescopically folding stand on each side of the staircase is provided with one support assembly, consisting of a (relative to the stand) stationary support unit and (relative to the stand) a movable support device, while at each of said stairways segments on each side of the stand, preferably above said support assembly, a connected rope or similar flexible drawbar which is guided to a common winding drum which, in the longitudinal direction of the stand, is also axially movable bearing-driven in the same direction by means of an electric motor incorporated therein.

In this case, at least one rope is fastened to each end of the grandstand on the winding drum, which with its available arms is counter-wound around the drum. It is particularly advantageous if one rope is attached at each end of the rooftop drum to a central area between each winding area and to each unwinding area, each of which is connected to the staircase segments of the rooftop under the drum. In at least partially extruded, preferably tubular, winding drum, supported obliquely with respect to its longitudinal axis, the supporting rolling elements are mounted, a bi-directional electric motor, the stator connected to a guide, adapted to provide its support during rotation and at the same time to move of the drum in the axial direction of the latter

Said bus preferably comprises a slide with which the stator of the electric motor is connected, as well as a guide groove in which said slide is movably inserted in the axial direction of the drum. Further, the support roller elements on which the drum is supported are positioned obliquely below the latter, with respect to its longitudinal axis, and - with respect to the longitudinal axis of the drum - at an angle corresponding to the angle of inclination of the helix when winding the rope on the drum or. unwinding the rope from the drum.

The preferred embodiment of the stand according to the invention is also characterized in that each step segment on each side of the stand comprises a lower horizontal support, on which a vertical support is attached, and on the latter, an upper horizontal support is mounted cantileverly, with extensions located on both sides of the stand. an upper platform, preferably comprising at least one step and, if necessary, at least one seating position, shall be provided in the upper horizontal beams of each stair segment. '

It is furthermore characteristic of the tribune according to the invention that the support assembly available on each side of the respective staircase unit consists of a rigid support unit which is rigid or non-rigid. inextricably linked to the rest of the load-bearing elements of the staircase segment and which, in the case of the unloaded grandstand or. in the unladen state, it is located on a characteristic and constant parallel distance from the respective substrate, as well as from the movable or. temporary support arrangements, including roller support elements, in particular wheels, which are / are supported by a limited force only.

In a preferred embodiment of the stand according to the invention, each movable support device comprises support wheels, each of which is mounted on one of the pivoting levers, at least one of which is supported by a spring. It is particularly advantageous if one fixed support unit is fixed to each of the sides of the staircase segment of the stand at the lower horizontal bracket, whose surface is as wide as possible, ie. the bulk bearing surface is held at a parallel parallel distance from the respective base at the unloaded stand, and at the base at the loaded stand, wherein the pivots of the movable support device are provided at said end, and at one end of one said wheel being mounted, its end supported by a spring on the other side of the pivot, while a wheel is mounted on one end of the rest of the said levers, and its end opposite the associated pivot being articulated, namely by means of an elongated through holes and pins and therefore with the possibility of rotation and translation, connected to the aforementioned or first-mentioned lever. Beneath the horizontal support of the respective staircase segment of the tribune, and in particular the stationary support unit located and connected to each staircase segment, are preferably arranged under levers and movable support devices between the wheels, so that, in the relaxed state of the tribune, they are thanks to and, thanks to the arrangement of their pivots, a fixed support unit is thereby connected to them, kept at a distance from the substrate and parallel to the substrate. On the other hand, there is a fixed support unit located below and connected to each horizontal carrier on the side of each stair segment, which are arranged under the levers and movable support devices between the wheels, so that in the laden state of the stand, in the presence of the audience, thanks to the predetermined force. the springs of the two said levers are at least substantially aligned with each other so that, due to the arrangement of their pivots, the associated stationary support unit, with its surface as large as possible, is in contact with the base. The aforementioned spring is preferably designed as a pressure screw spring and is also preferably supported by a stationary support unit.

An example of the construction of a tribune according to the invention will now be explained in further detail in connection with the accompanying drawing, where FIG. 1 panel according to the invention, but with the drive train removed, in perspective; FIG. 2 supporting assembly of one of the stair segments, in side view; FIG. 3 is a perspective view of the grandstand assembly of the invention;

FIG. 4 is a more detailed view of the drive drum coil drum of FIG. 3.

The stand (Fig. 1) is basically made up of a suitable number of stair segments 1, Γ, 1, ..., which are in depth, i.e. The widths of the floor plan, which are equal or at least equal to one another, and in height, are adapted to be positioned one below the other or. pulling the other out from under the other. The aforementioned staircase segments, which will be hereinafter referred to simply as numerically numbered 1 for the sake of simplicity, comprise originally designed support assemblies 2, one on each side, except that the panel is also equipped with an imaginatively designed drive assembly 3.

In the preferred embodiment of the panel shown in the accompanying drawing, the respective staircase segment 1 is made of two horizontal side rails 11 mounted on each side, and a vertical carrier 12 is disposed on each of the latter, one vertically mounted to the back of the panel. a cantilevered upper horizontal support 13, through which a support platform 14 is mounted on each side of the stand, can be implemented in different ways depending on the wishes and needs of the client. In the example shown in FIG. 1, steps 141 are provided on one part of the platform 14 and benches 142 on the rest, which, of course, in the case of stands, can of course be dropped off without further delay or may be provided as removable.

Under each of said staircase segments 1, there is provided at each side one support assembly 2, which, in the example shown, is located below the lower horizontal carrier 11 of the staircase segment 1. Each support assembly 2 consists of (with respect to the tribune) a stationary support unit 21, such as also from temporary or. (again according to the panel) movable support devices 22.

In this case, the stationary support unit 21 of each support assembly 2 is rigidly connected to the rest of the staircase segment 1, in the specific case it is attached to the lower horizontal support 11, at a fixed distance from it, and in addition to the unloaded panel with its lower or . the contact surface 210 also at a suitable, constant parallel distance from the surface available at all times, which is provided by the design of the movable support device 22 in the following.

The movable support device 22 of each support assembly 2 is designed with wheels 22 ', 22 which, in the case of a loaded or laden stand, are in contact with each other on an available basis. In the present case, these are two wheels 21 ', 22 which are supported by a predetermined but limited force towards the base. This support force of the wheels 2Γ, 22 of the movable support device 22 is so chosen that, in the unloaded stand (namely when there is no audience), only the wheels 2Γ, 22 rest on the base, while the stationary support unit 21, namely its against the base inverted contact surface 210, away from the base and parallel to the latter. When spectators are present at the stand and are

The -1010 stands thus in a loaded state, its own weight including the weight of the spectators exceeds the force of the wheel support 2Γ, 22, which results in the withdrawal of the wheels vertically upwards, which causes the stand to gradually lengthen until it rests on the ground. a stationary support unit 21, with its surface-wide contact surface 210, which is parallel to the ground throughout the stand. As soon as unit 21 is attached to the substrate, this means, of course, that the total load of the stand, including the weight of the audience on the substrate, instead of through the wheels 22 ', 22 is uniformly distributed over substantially larger surfaces 210 of the stationary support units 21. In the present case, the movable support device 22 designed in such a way that each of the wheels 22 ', 22 is mounted on a corresponding lever 23, 24, said levers 23, 24 being pivotable to each other and simultaneously spring-loaded. Nozzles 230, 240 of said levers

23, 24 are mounted just on a fixed support unit 21. A longer lever 23, one arm 231 of which is provided with a wheel 22 ', and its opposite arm pivot 230, which is supported by a pressure spring 233, is articulated, respectively. with the possibility of rotation and simultaneous translation, a shorter lever is attached to its end 241

24, to which the opposite end 242 is mounted a wheel 22. The connection of said levers 23, 24 is optionally made in such a way that the lever 23 is provided with pin 234 and the remaining lever 24 is provided with an elongated hole 243 through which said pin is inserted. 234. Such linkage of the levers 23, 24 allows the loads from the staircase segment 1 of the stand to be transmitted uniformly in all directions on the wheel 22 ', 22 through the lower horizontal carrier 11, which means that the stationary support unit 21 is located parallel to the base at all times, or that the grandstand during loading or. possession cannot tilt.

In FIG. 2, the support assembly 2 is shown in the unladen state and the stationary support unit 21 is offset from the base by its contact surface 210;

-1111 which in the shown state of the stand is supported by the wheels 22 ', 22 of the movable support device 22. The load of the stand, in which the wheels 22', 22 are withdrawn and in which the stationary support unit 21 is supported, is solely dependent on the deformability or . characteristics of the spring 233. The stationary support unit 21 is thus designed with a relatively large contact surface 210 with which the loaded stand rests on the base. It will be understandable to the average expert, relieved or unladen stands without further mobility and can be moved on the ground thanks to the 22 ', 22 wheels. On the other hand, it is also apparent that despite the significant increase in the stand load due to the presence of even more spectators on it, the pressure on the ground can be kept within reasonable and permissible limits due to the fact that in such a case the stand instead of the wheels 22 ', 22 variable support devices 22 staircase segments 1 rests on a base over relatively large contact surfaces 210 fixed supports 21 identical staircase segments 1.

For the purpose of assembling and disassembling the stands or moving staircase segments 1 under one another or. pulling them out from underneath the stand is also equipped with a drive train 3. It is fully integrated inside the stand at its rear, which allows the installation of the stand directly against the wall of the sports facility, which can make space in the sports facility very to use rationally. The drive assembly 3 as shown in FIG. 3 and 4, it also extends, in its axial direction, along the entire length of the stand, which is movable in its axial direction, thereby receiving a winding and electromotor driven winding drum 31 for winding or. unwinding of rope 32 or similar flexible traction element extending on both sides of the platform and appropriately connected to the individual staircase segments 1 of the panel. The aforementioned flexible traction element, which in the example shown is a steel wire rope, will be further simplified in the following

-1212 named as rope 32. The method of moving staircase elements 1 using rope 32 is otherwise known. Unlike the prior art solutions, which have an electric motor with a drum for unwinding / winding the traction element, one rope 32 is available on the stand of the invention on each side of the stand, with the rope 32 on either side of the stand thatist drum 31 oz. is unfolding from it. Said rope 32 on each side of the rostrum comprises two arms 321, 322, with one arm 321 leading from drum 31 via diversion rows 36, 37 to stair segments 1, and the remaining arm 322 returning from there to drum 31. Thus, on the drum 31 on each side of the stand, there are two contact areas of each of the two ropes 32, one winding area 311 and one unwinding area 312, while in the intermediate region 313 between them the rope 32 is attached to the drum 31. the arms 321, 322 of the rope 32 extend through the diversion ropes 36, 37, and further pressure of the drum 31 is provided against the support roller elements 35.

Drum 31 is electromotor driven, in which case it is at least partially hollow or non-electric. extracted, preferably tubular-shaped drum 31 housing a bi-directional and, preferably, not shown brake, electric motor 33 whose stator 331 is housed outside the drum 31 of the guide 34. The guide 34 is shown in an extremely simplified form and scope a slider 341 inserted in a guide groove 342 extending in the axial direction of the drum 31. The slider 341 provides a support to the electric motor 33 that is required to rotate the drum 31 and, on the other hand, allows the rotating drum 31 to be moved in its axial direction. . In order to ensure the axial movement of the drum 31, which allows winding the rope 32 in the form of a helix in a step dependent on the axial displacement of the drum 31, the drum 31 is supported by an angle with respect to its central longitudinal axis 310 of the supporting rolling elements 35, which are preferably conical for better fit. The expert will therefore understand that

-1313 The angle of deviation of the axis of the roller elements 350 from the central axis 310 of the drum 31 corresponds to the angle of the helix at which the rope 32 is wound onto the drum 31 or. unwinding of rope 32 from drum 31.

When the motor 33 is switched on, the stator 331 is naturally retracted due to the insertion of the slider 341 in the groove 342, so that the (non-displayed) rotor of the motor 33 rotates in the desired direction in the drum 31. With said rotor via a suitable transmission assembly, e.g. via the planetary gearbox, the drum 31 connected internally starts to rotate in the desired direction, and thanks to its support on the obliquely mounted roller support elements 35, it simultaneously moves in its axial direction with the motor 33. Each of the ropes 32, which are each fastened on the side of the stand 31 to the drum 31 and to a certain extent wrapped around it, is simultaneously supported by one of its arms 321 or 322 with a certain intensity on the drum 31 and the remaining arm 321 or 322. it proceeds equally intensively from it, resulting in a steady and coordinated movement of the rope 32 connected stair segments 1. After stopping the engine 33 and starting it in the opposite direction, the opposite is true, but in any case the movement of segments 1 is also the case here. evenly and harmoniously. Because rope 32 is available on both sides of the platform, and because ropes 32 on both sides of the platform are identical and guided on the same winding drum 31, there is virtually no reason not to move the lateral areas of the platform simultaneously. This means that, despite the relatively small depth, the stand can also be relatively long. wide, so it is very convenient for a truly rational use of space in any sports facility.

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Claims (18)

PATENT APPLICATIONS 1. Telescopically folding stands, consisting of an appropriate number of sub-adjustable or adjustable stands. the second from the other drawable stair segments (1) which are movable by means of a drive train (3), in particular by winding a rope (32) or a similar flexible traction element on a winding drum (31) driven by a suitable motor, in particular an electric motor ( 33), characterized in that each of the stair segments (1) on the sides of the tribune comprises at least one support assembly (2), consisting of a stand-up support unit (21) and a stand-up support unit (22) relative to the stand. , and that on each of said stair segments (1) on each side of the trumpet, preferably above said support assembly (2), a rope (32) or similar flexible traction device is connected, leading up to the entire stand of the common winding drum (31 ) which, in the longitudinal direction of the tribune, is axially movable bearing, driven in the same direction in the same direction, driven by an electric motor (33). A stand according to claim 1, characterized in that at least one rope (32) is secured at each end of the stand at the winding drum (31) and with its two arms (321, 322) attached at each end. 3. A stand according to claim 2, characterized in that at least one rope (32) is fastened at each end of the stand on the winding drum (31) in the central area (313) between each winding area (311) and each unwinding area (312). , whose arms (321, 332) are permanently connected to the staircase segments (1) of the grandstand via the drum (31) arranged in the diversion ropes (36, 37). -1515 Tribune according to claim 1, characterized in that it is provided in at least partly a substantially inclined and preferably tubular winding drum (31) supported by obliquely mounted support elements (35) with respect to its longitudinal axis (310) and the latter additionally pressed thanks to the guidance of the legs (321, 322) of the rope via the diversion ropes (36, 37) arranged below the drum (31), a two-way electric motor (33) is mounted, the stator (331) of which is connected to the guide (34) intended for providing its support during rotation, and at the same time also providing for the synchronized movability of the drum (31) in its axial direction. Panel as claimed in claim 4, characterized in that the guide (34) comprises a slide (341) to which the stator (331) of the electric motor (33) is connected, as well as a guide groove (342) in which there is an axial direction of the drum. (31) said slide (341) being movably inserted. 6. A stand according to claim 4, characterized in that the support roller elements (35) on which the drum (31) is supported are positioned obliquely below the latter in relation to its longitudinal axis (310) at an angle corresponding to the angle ascending the helix when winding the rope (32) onto the drum (31) or unwinding the rope (32) from the drum (31). 7. A stand according to claim 1, characterized in that the respective stair segment (I) on each side of the stand comprises at least one lower horizontal support (II) arranged at a distance from the base and on which a vertical support (12) is attached. ) and the upper horizontal bracket (13) is mounted on the latter, and a platform (14) is mounted over the upper horizontal brackets (13) of each stair segment (1). -1616 8. A stand according to claim 7, characterized in that the platform (14) comprises at least one step (141). 9. A stand according to claim 7, characterized in that the platform (14) comprises at least one seat (142). 10. A stand according to claim 1, characterized in that each support assembly (2) of each stair segment (1) of the stand consists of a rigid or rigid support unit (21) relative to the stand. inextricably linked to the rest of the frame or. the supporting elements of the staircase assembly (1) and which in the case of the unloaded grandstand or. in unburdened state, it is located at a constant parallel distance from the respective substrate, as well as from the temporary or. with respect to the panel-movable support device (32), which includes the roller support elements, in particular the wheels (22 ', 22), which are / are only supported by a limited force in the direction of the base. 11. A stand according to claims 1 and 10, characterized in that each movable support device (22) comprises at least two support wheels (22 ', 22), at least one of which is mounted on one of the pivoting levers (23, 24), at least one of which is supported by a spring (233). A stand according to claims 1, 10 and 11, characterized in that at least one fixed support unit (21) is fixed to the lower horizontal bracket (11) of the respective staircase segment (1), each having a substantially flat contact surface (210) is permanently kept at a parallel distance from the respective substrate in the unloaded stand, and in a uniform rest on the base in the loaded stand, while at -1717 said stationary support unit (21) also provided pivots (230, 240) of the levers (23, 24) of the movable support device (22), wherein a wheel (22 ') is mounted at one end (231) of one lever (23) , while its end (232) on the other side of the pivot (230) is supported by a spring (233), and a wheel (22) is mounted on one end (242) of the remaining lever (24), its opposite of the pivot (240), the adjacent end (241) is articulated, namely rotatable and translational, connected to the aforementioned lever (23). 13. A stand according to claims 1 and 10 - 12, characterized in that, under each horizontal carrier (11) of the respective stair segment (1), a fixed support unit (21) located and connected thereto is disposed under the levers (23, 24) and movable support devices (22) between the wheels (22 ', 22) such that, in the unburdened state of the stand, due to the force of the spring (233), the levers (23, 24) are open and connected to them by the arrangement of their pivots (230, 240) the stationary support unit (21), with its contact surface (210), thus being kept at a parallel distance from the base. A stand according to claims 1 and 10 - 12, characterized in that, under each horizontal carrier (11) of the respective stair segment (1), a fixed support unit (21) located and connected thereto is disposed under the levers (23, 24) and movable support devices (22) between the wheels (22 ', 22) such that, in the laden state of the stand, in the presence of the audience, thanks to the exceeding of a predetermined force of the spring (233) of the lever (23, 24) on the basis of mutual rotation and translation substantially aligned so that, due to the arrangement of their pivots (230, 240), the associated stationary support unit (21) with its contact surface (210) is in even contact with the base. -1818 15. A stand according to claim 11, characterized in that the spring (233) is a pressure screw spring. 16. A stand according to claim 15, characterized in that the spring (233) is a pressure screw spring that is supported by a stationary support unit (31). 17. A stand according to claim 12, characterized in that the levers (23, 24) of the movable support device (22) are articulated interconnected, namely, with the possibility of rotation and translation. A stand according to claim 17, characterized in that the levers (23, 24) of the movable support device (22) are interconnected by means of an elongated through hole (243). which is available on one lever (24) and a pin (234) which is available on the remaining lever (23) and inserted transversely through said elongated hole