EP3659467A1 - Height-adjustable device - Google Patents

Abstract

Height-adjustable device (1), with at least two synchronously height-adjustable lifting devices (2, 3), each of which has a standing element (4, 7) and a lifting element (5, 8) which is height-adjustable relative to it, the height adjustment being effected by tension elements (6, 9) takes place, which are formed by deflection devices (11, 13) for lifting each lifting element (5, 8) relative to the associated stand element (4, 7); wherein each tension element (6, 9) is non-positively and / or positively attached to two lifting devices (2, 3) and an elongation in the area of the first lifting device (2) causes a synchronous shortening in the area of the second lifting device (3); and each pulling element (6, 9) is designed to lift only one lifting element (5, 8) relative to the associated standing element (4, 7). In order to ensure a synchronous height adjustment of the lifting devices (2, 3), a locking device (26) for locking each tension element (6, 9) by means of non-positive and / or positive engagement on this tension element (6, 9). In addition, the locking device (26) is designed to synchronize the movement of the tension elements (6, 9).

Description

The invention relates to a height-adjustable device, with at least two synchronously height-adjustable lifting devices, each having a standing element and a lifting element which is height-adjustable relative thereto, the height adjustment being carried out by pulling elements which are formed by deflection devices for lifting each lifting element relative to the associated standing element; wherein each tension element is non-positively or positively attached to two lifting devices and an elongation in the area of the first lifting device causes a synchronous shortening in the area of the second lifting device; and each pulling element is designed to lift only one lifting element relative to the associated standing element.

Height-adjustable devices of the type mentioned at the outset, in particular so-called lifting tables, are known and are used, for example, in the office area or in airplanes, in particular VIP airplanes. Such lifting tables regularly have two lifting columns. When adjusting the height of such a device, it can be problematic to synchronize the lifting movement between two or more lifting devices and to lock them in the desired height without jamming or other problems occurring. It can be particularly problematic with corresponding tables in VIP aircraft, where the height adjustment is usually carried out by flight attendants from the front of the table. Here there is a regular uneven application of force to the lifting columns.

A lifting device of the type mentioned is out EP 1 987 734 B1 known. Proceeding from this, the present invention has for its object to provide a lifting device of the type mentioned that facilitates a synchronous height adjustment, enables a secure locking at the desired height and is simple in structure.

This object is achieved in that a locking device is provided for locking each pulling element by means of non-positive and / or positive engagement on this pulling element and the locking device is additionally designed to synchronize the movement of the pulling elements.

First, some terms used in the context of the invention are explained.

According to the invention, a height-adjustable device can comprise, in particular, a piece of furniture or furniture, for example tables, worktops or the like.

With the stand elements, the device stands on the installation surface. It can be, for example, table legs or their parts which are immovable relative to the installation surface.

A lifting element is height-adjustable relative to each stand element. The lifting elements carry, for example, a table top or the like.

Traction elements in the sense of the invention can transmit the tensile forces required for the height adjustment, it can for example, preferably flexible belts, bands, chains or the like. By means of deflection devices, they are designed to lift each lifting element relative to the associated standing element. The deflection devices, preferably deflection rollers, can serve both to merely deflect the force of the tension elements and to support the lifting process in the sense of a pulley block. For example, according to the invention, a deflection device can be arranged in the lower region of a lifting element; by means of this deflection device, lifting takes place in the sense of a block and tackle by means of a tension element deflected around about 180 °.

Each tension element is non-positively and / or positively attached to two lifting devices. The attachment is preferably carried out with one end of a pulling element each on the static areas (standing element) of a lifting device. The kinematics are designed such that an elongation in the area of the first lifting device causes a synchronous shortening in the area of the second lifting device. As will be shown in more detail below, this synchronizes the lifting movements of two lifting devices.

Each pulling element is designed to lift only one lifting element relative to the associated standing element. According to the invention, two lifting devices are connected to one another by at least two pulling elements, each of these pulling elements is designed (preferably via deflection rollers) for lifting only one lifting element by shortening it in the area of this lifting element. The two tension elements interact with each other by counter-movement, effect the lifting movement of both lifting elements and the synchronization of this movement.

According to the invention, it is provided that a locking device is provided for locking each tension element by means of non-positive and / or positive engagement on this tension element. By locking each pulling element, the further movement of these pulling elements and thus also the lifting movement of the lifting device are blocked or locked.

In the device according to the invention, the tension elements thus have the double function of on the one hand synchronizing the lifting movement and on the other hand locking the set height position by blocking these tension elements themselves by means of the locking device according to the invention. According to the invention, separate and frequently susceptible locks in the lifting devices themselves are not required.

The locking device according to the invention is additionally designed such that the movement of the tension elements takes place synchronously. This means that the locking device kinematically couples the usually opposite movements of, for example, two tension elements by means of corresponding devices in this locking device in such a way that a movement of a tension element in one direction brings about a preferably opposite, synchronous movement of the second tension element. This synchronization by the locking device is preferably provided in addition to the synchronization by the kinematics of the connection of the tension elements with standing elements and lifting elements and improves operation and, in particular, uniform lifting movement of the device according to the invention. In particular, such a synchronization can be provided by the locking device if it is designed to drive the tension elements.

According to the invention, it is preferred that each traction element is non-positively connected to each stand element; and that it is guided in the area of a lifting device via a pulley arranged on the lifting element. The shortening of the tension element in the area of the lifting element with pulley raises the corresponding lifting element, the synchronous elongation of the tension element in the area of the second lifting device is preferably used in the manner shown below in the exemplary embodiments via deflection rollers arranged in the upper area of the lifting element of the second lifting device and is synchronized therewith the lifting movement of this second lifting element inevitably also prevents this second lifting element from being lifted too strongly, since an additional elongation of the tension element would then be required.

According to the invention, it is preferred if the locking device is designed for non-positive and / or positive engagement with each tension element in the region of the guidance of these tension elements between the lifting devices. In particular, it can be designed according to the invention as a central unit, which can lock all the tension elements in one area centrally between the lifting devices (table legs). Locking only in a central unit significantly simplifies handling and operation. In particular, it is not necessary according to the invention to provide separate locks in the individual lifting devices and, if appropriate, complex devices for distributing a locking signal to a plurality of locking devices in these lifting devices. A central locking also ensures uniform force distribution across the various lifting devices.

The locking device can also be designed to drive the tension elements. It can therefore be used for manual or motor drive of at least one, preferably all pulling elements, so that a height adjustment takes place by actuating the drive. In this embodiment of the invention, the traction elements are thus not only used to synchronize the lifting movement, while the lifting force is applied, for example, by pressing or pulling on the table top. Instead, they also serve directly to actuate the lifting devices.

According to the invention, the locking device can have a shaft (preferably with a gear, friction wheel or the like placed thereon) for the non-positive and / or positive movement, locking and synchronization of the tension elements. The term wave designates an element that can cause a corresponding longitudinal movement of the tension element or the tension elements by rotation. There may be a frictional or frictional connection between the shaft (or toothed wheel or friction wheel) and the tension element, but a positive connection is preferred according to the invention for the synchronization of the movements.

It is therefore particularly preferred according to the invention that the tension elements have toothed belts and the shaft meshing with gear wheels. It can be provided according to the invention that the traction elements are locked by blocking a rotary movement of the shaft. Gears or friction wheels placed on the shaft can be connected to the shaft, for example, by a feather key connection.

To secure the frictional connection and / or positive connection between the shaft and tension elements, additional deflection rollers can be provided in the area of the lead and / or lag of the tension elements relative to the shaft. These pulleys can For example, cause toothed belts to be guided over a sufficiently large circumferential section of the shaft and thus a secure form fit and / or force fit results. The deflection rollers can be freely rotating on an axis, ie not kinematically coupled to the shaft described above. Alternatively, they can be non-rotatably connected to the shaft. The non-rotatable connection is preferably not only made via the tension elements, for example toothed belts, but additionally by means of a suitable kinematic connection, such as for example gears or the like.

The tension elements are preferably designed such that they do not experience any significant elongation during operation under the intended operating conditions. No substantial elongation means that any stretching / elongation does not affect the operation of the lifting device and the synchronism of the lifting movement. The tension elements can be made of a correspondingly tensile material or have reinforcing elements. For example, toothed belts can be provided with steel strands.

The device according to the invention can be provided with two lifting devices, for example as a table with two lifting columns. Such an embodiment can be used, for example, as a table in vehicles or aircraft, for example VIP aircraft. The device according to the invention can preferably be designed as a table, regardless of the number of lifting devices.

When configured as a table, the locking device is preferably designed as a central unit below the table top between the lifting devices (table legs or lifting columns).

The device according to the invention can have at least one device for receiving lifting loads. For example, gas pressure springs can be arranged in the lifting devices, which largely compensate, for example, or somewhat overcompensate for the weight of the height-adjustable part of the device. This facilitates manual height adjustment and / or permits height adjustment by driving the pulling elements with the application of lower forces.

To explain the device according to the invention, reference is made to the above statements.

Figur 1a, 1b:

eine schematische Darstellung des Grundprinzips der Höhenverstellung wie es in der erfindungsgemäßen höhenverstellbaren Vorrichtung genutzt wird;

Figur 2:

eine schematische Darstellung eines Ausführungsbeispiels einer erfindungsgemäßen Vorrichtung;

Figur 3:

eine schematische Darstellung eines Ausführungsbeispiels einer Arretierungseinrichtung;

Figur 4:

eine schematische Darstellung eines Ausführungsbeispiels einer Umlenkrichtung in einer Hubeinrichtung;

Figuren 5- 7:

schematische Darstellungen eines Ausführungsbeispiels einer Spanneinrichtung zum Spannen der Zugelemente.

The invention will now be described by way of example with reference to advantageous embodiments with reference to the accompanying drawings. Show it:

Figure 1a, 1b:

a schematic representation of the basic principle of height adjustment as used in the height-adjustable device according to the invention;

Figure 2:

a schematic representation of an embodiment of a device according to the invention;

Figure 3:

a schematic representation of an embodiment of a locking device;

Figure 4:

a schematic representation of an embodiment of a deflection direction in a lifting device;

Figures 5-7:

schematic representations of an embodiment of a tensioning device for tensioning the tension elements.

With the help of Figures 1a and 1b The basic principle of a height adjustment, as used in an exemplary embodiment of a device 1 according to the invention, is shown below. The explanation is made according to the exemplary embodiment with a first lifting device 2 and a second lifting device 3. The first lifting device 2 comprises a first standing element 4 and a first lifting element 5, which can be moved in and out of the first standing element 4, as well as a first pulling element 6 Analogously, the second lifting device comprises a second standing element 7, a second lifting element 8 and a second pulling element 9. The first pulling element 6 is connected in the first lifting device 2 to the first standing element 4 at the first connection point 17 and is guided vertically upwards and via a first front deflection roller 10 of a first deflection device 11 guided horizontally to a second front deflection roller 12 of a second deflection device 13 of the second lifting device 3 and there vertically downwards via the second front deflection roller 12 and upwards again via a lower deflection roller 14 and with the second standing element 7 at the second connection point connected 16. Analogous to the first tension element 6, the second tension element 9 is connected to the second standing element 7 at the second connection point 16 and is guided vertically upwards to a second rear deflection roller 18 and from there horizontally to a first rear deflection roller 19. In the first lifting device 2, the second tension element 9 is guided vertically downwards from the first rear deflection roller 19 to a first lower deflection roller 15, from there upwards and is connected to the first stand element 4 at the connection point 17.

A height adjustment takes place via a movement of the first and / or the second tension element 6, 9. The movement is triggered by the application of force on the tension elements 6, 9. Two variants are possible. In one variant, a tension element is subjected to a force. This leads to a movement of the tension element and the movement sequence described below. According to a second variant, the force is applied to both tension elements simultaneously, in such a way that an opposing movement of the tension elements is triggered synchronously. The movement sequences of the tension elements 6, 9 described below then run synchronously.

A movement of the second tension element 9 to the left leads to a lifting of the second lifting element 8 due to the connection of the second tension element 9 with the second standing element 7. The lifting of the second lifting element 8 leads to an elongation of the distance 20 between the first front deflection roller 10 and the first connection point 17 and a synchronous shortening between the second connection point 16 and the second lower roller 14. Synchronously, there is an elongation 22 between the second rear deflection roller 18 and the second connection point 16, which leads to a synchronous shortening 23 between the first connection point 17 and the first lower deflection roller 15 of the first lifting device 2, the first lifting element 5 being pulled upward, that is to say raised, due to the shortening of the distance 23 from the first pulling element 6. Moving the first pulling element 6 to the right would result in an analogous movement sequence.

A movement of the second tension element 9 to the right leads to a lowering of the first and second lifting elements 5, 8, because in this way the distance 20 is shortened in the first lifting device. The shortening of the distance 20 has the result that the first lifting element 5 is pulled back into the first supporting leg 4 by the second pulling element 9, that is to say it is lowered. At the same time, the distance 23 in the first lifting device 2 is lengthened. The lengthening of the distance 23 means that the distance 22 is shortened, which in turn pulls the second lifting element 8 into the second standing element 7, that is to say it is also lowered. It also applies here that a movement of the first pulling element 6 to the right results in an analogous movement sequence of the lifting devices 2, 3.

A first exemplary embodiment of a height-adjustable device 1 according to the invention is shown in FIG Fig. 2 shown. The device shown comprises a first lifting device 2 with a first standing element 4 and a lifting element 5. Furthermore, the device comprises a second lifting device 3, which consists of a second standing element 7 and a second lifting element 8. In both lifting devices 2, 3, the lifting elements 5, 8 can be moved into and out of the standing elements 4, 7 and vice versa. A crossmember 25 is arranged on the lifting devices 2, 3 and connects the lifting devices 2, 3 to one another.

In addition to the schematic representation of the basic principle, the device 1 according to the exemplary embodiment has a locking device 26 through which both pulling elements 6, 9 are guided and which is designed such that it can be used to generate a locking of the movement of the pulling elements 6, 9. The locking device 26 is arranged centrally on the cross member 25 between the two lifting devices 2, 3. Due to the central arrangement of the locking device 26 between the lifting devices 2, 3, the path lengths are between the lifting devices of the same length, whereby a synchronous transmission of the tensile forces occurring to the lifting devices 2, 3 is achieved, which in turn has the consequence that the lifting elements 5, 8 are moved up or down at the same time and jamming is avoided. Even in the locked state, canting can be reliably avoided with one-sided loading due to the synchronous transmission of the tensile forces.

The Fig. 3 shows a possible embodiment for a locking device 26 according to the invention. The locking device 26 consists of a cover plate 27, by means of which the locking device 26 can be fastened to the cross member 25, and two side parts 28. The first and second tension elements 6, 9 are each centered over a first and second central deflection roller 29, 30 through the locking device 26. The central deflection rollers 29, 30 are rotatably connected to a central shaft 31. In addition, lateral deflection rollers 32, 33, 34, 35 are provided in front of and behind the central deflection rollers 29, 30 for each tension element 6, 9, the side deflection rollers 32, 34 and 33, 35 lying next to one another each being loosely supported on a common axis 36, 37 are arranged. In order to enable the required opposite direction of movement of the tension elements 6, 9, the first tension element 6 is guided over the underside of the first central deflection roller 29 and the second tension element 9 over the top side of the second central deflection roller 30. The guidance through the lateral deflection rollers 32, 33, 34, 35 is adapted accordingly. The movement of the tension elements 6, 9 preferably takes place via a rotation of the central shaft 31, which for this purpose can be connected to an electric motor or a crank (both not shown).

The central shaft 31 can be blocked in different positions. In the exemplary embodiment shown, a locking disk 38 is fastened to the central shaft 31, on the circumference of which various bores are provided, into which a spring-loaded locking pin 39 can be guided for locking purposes. The locking bolt is fastened in a side part 28 of the locking device 26 and, due to the spring force, is seated in the next hole. Using a Bowden cable or a rod system, there is the possibility of loosening or setting the locking pin 39 from other positions (e.g. end face of the table top).

The tension elements 6, 9 can be designed as toothed belts. As a toothed belt z. B. timing belt from the manufacturer Mädler GmbH, which is provided with the HTD profile, can be used. This profile is characterized by its use in high-performance belts and ensures a low-backlash belt drive. A TPU belt (thermoplastic polyurethane) with a steel tensile cord was selected (see: http://www.maedler.de/product/1643/ 1616/945 / toothed belt-meterware-pu-profile-htd). The pulleys are designed accordingly as toothed belt wheels.

In the Figure 4 An exemplary embodiment of a deflection device 11, 13 is shown in a lifting device 2, 3, which in the case shown is the second lifting device 3 with the deflection device 13. The first lifting device 2 with the deflection device 11 is designed analogously to this. The deflection device 13 comprises a second front and rear deflection roller 12, 18, both of which are arranged loosely on an axis 40. The axis 40 is preferably arranged rotatably via a bushing 42 on the lifting element 8 and fixed via an adjusting ring 43. Alternatively, the axis 40 can also be fixed in terms of rotation, preferably by means of a transition fit be connected to the lifting device 3; Deflection rollers are then rotatably mounted on the rotationally fixed axis 40 via bushings. The second tension element 9 is deflected via a second lower deflection roller 14, guided upwards again and fastened together with the first tension element 6 to the second stand element 7 via a belt clamping plate, which consists of an auxiliary plate 44, a spacer 45 and a clamping plate 46.

Due to the positive connection of the tension elements 6, 9 to the central shaft 31, which is locked, it is necessary to individually tension all four sections of the tension elements 6, 9. An embodiment of a possible tensioning device 60 can Figures 5 , 6 and 7 which show the tensioning device 60 on a second lifting device 3. The design of the tensioning device 60 is correspondingly analog for the first lifting device 2. In the Figure 5 the second lifting element 8 of the second lifting device 3 is shown. On the second lifting element 8, the second deflection rollers 12, 18 are arranged on the axis 40, via which the tension elements 6, 9 are guided. The second lifting element 8 is attached to the cross member 50. The cross member 50 connects the first and second lifting devices 2, 3 to one another. In addition, the locking device 26 is also attached to the traverse 50. In the Fig. 6 it is shown that the traverse 50 has an opening above the fastening with the second lifting device 3, in which the tensioning device 60 is arranged. As in Figure 7 Shown in more detail, the tensioning device 60 comprises tensioning blocks 70 which are connected to the upper deflection rollers 12, 18 (not shown). The clamping blocks 70 are received in clamping plates 71 and connected via retaining screws 73. The clamping plates 71 are displaced by means of adjusting screws 72, the clamping plates having short elongated holes 74 in which the retaining screws 73 are guided. When the locking device 26 is adjusted inwards, the belt tension is reduced, when the adjustment is made outwards, the belt tension is increased.

Claims (14)

Height-adjustable device (1), with at least two synchronously height-adjustable lifting devices (2, 3), each of which has a standing element (4, 7) and a lifting element (5, 8) which is height-adjustable relative to it, the height adjustment by means of tension elements (6, 9) takes place, which are formed by deflection devices (11, 13) for lifting each lifting element (5, 8) relative to the associated stand element (4, 7);
wherein each tension element (6, 9) is non-positively and / or positively attached to two lifting devices (2, 3) and an elongation in the area of the first lifting device (2) causes a synchronous shortening in the area of the second lifting device (3); and
each pulling element (6, 9) is designed to lift only one lifting element (5, 8) relative to the associated standing element (4, 7);
characterized in that a locking device (26) is provided for locking each tension element (6, 9) by means of a force-fitting and / or positive engagement on this tension element (6, 9) and the locking device (26) additionally for synchronizing the movement of the tension elements (6 , 9) is formed. Device according to claim 1, characterized in that each traction element (6, 9) is non-positively and / or positively connected to each end element (4, 7); and that it is in the area of a lifting device (2, 3) is guided over a pulley arranged on the lifting element (5, 8). Device according to claim 1 or 2, characterized in that the locking device (26) for non-positively and / or positively engaging each traction element (6, 9) in the region of the guidance of these traction elements (6, 9) between the lifting devices (2, 3) is trained. Device according to one of claims 1 to 3, characterized in that the locking device (26) is additionally designed to drive the tension elements (6, 9). Device according to one of claims 1 to 4, characterized in that the locking device (26) has a shaft (31) for the non-positive and / or positive movement, locking and synchronization of the tension elements (6, 9). Apparatus according to claim 5, characterized in that the tension elements (6, 9) have toothed belts and the shaft (31) gears meshing therewith. Apparatus according to claim 5 or 6, characterized in that the traction elements (6, 9) are locked by blocking a rotary movement of the shaft (31). Device according to one of claims 5 to 7, characterized in that in the area of the leading and / or trailing of the tension elements (6, 9) relative to the shaft (31) deflection rollers (32, 33, 34, 35) for securing the frictional connection and / or positive engagement of the tension elements (6, 9) with the shaft (31) are provided, the deflection rollers (32, 33, 34, 35) are preferably rotatably mounted on an axis (36, 37). Device according to one of claims 5 to 8, characterized in that the connection of friction wheels and / or gearwheels to the shaft (31) takes place via a feather key connection. Device according to one of claims 1 to 9, characterized in that the tension elements (6, 9) are designed such that they do not experience any significant elongation during operation under the intended operating conditions. Device according to one of claims 1 to 10, characterized in that it has two lifting devices (2, 3). Device according to one of claims 1 to 11, characterized in that it is designed as a table. Apparatus according to claim 12, characterized in that the locking device (26) is designed as a central unit below the table top between the lifting devices (2, 3). Device according to one of claims 1 to 13, characterized in that it has at least one device for receiving lifting loads.

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