EP1982616A1

EP1982616A1 - Support structure

Info

Publication number: EP1982616A1
Application number: EP07425232A
Authority: EP
Inventors: Luciano Lucatello
Original assignee: Societa Vetraria Biancadese SAS
Current assignee: Societa Vetraria Biancadese SAS
Priority date: 2007-04-19
Filing date: 2007-04-19
Publication date: 2008-10-22

Abstract

A support structure with variable height for a surface (12) comprises at least two tiltable legs (21,31,41) and a support to which the at least two legs are pivoted by means of respective pivoting elements. The support structure comprises means for the controlled rotation of each pivoting element by a desired angle.

Description

The present invention regards a support structure for surfaces, in particular for tables with work surface with variable height.
Tables are known in which the user, according to his needs, can vary the height of the work surface from the ground, modifying the configuration of the table legs, which have, for example, a telescopic or tiltable structure.
The US patent US-A-3,738,286 describes a table in which each of the four legs is pivoted on a respective lateral face of a parallelepiped support, so that each leg can rotate around an axis perpendicular to its longitudinal axis. On each of the four lateral faces of the support, an eccentrically pivoted pin or block is present of circular or irregular polygonal shape, on whose lateral faces each leg can be in abutment. Consequently, according to the configuration of the block, each leg is positioned according to a different slope, thus also varying the height of the surface which it supports.
A table with a device of this type can vary the height of its own surface in a limited manner, since it is possible to adjust the tilt of the legs only according to restricted number of positions, or at most within a defined angular interval.
Moreover, to modify the tilt of the legs and consequently the height of the surface, one must separately act on each leg, a rather impractical operation and costly in terms of time. It is also difficult to ensure the perfect horizontality of the supported surface.
The main object of the invention is to provide a support structure with adjustable height according to an unlimited number of possible configurations.
An equally important object of the invention is to provide a functional adjustment mechanism such that with only one command, the adjustment is carried out of all legs simultaneously.
These and other objects are achieved by an support structure with variable height for a surface comprising at least two tiltable legs, and a support to which the at least two legs are pivoted by means of respective pivoting elements, characterised in that it comprises means for the controlled rotation of each pivoting element by a desired angle.
Due to a rotation of the pivoting elements in clockwise or anticlockwise sense, the tilt of the legs is modified, raising or lowering the work surface of the table sustained by the support structure.
The pivoting elements are mechanically connected to each other through gears or other transmission mechanisms (for example, belts, pulleys or levers), so that with a rotation of a pin, there corresponds an analogous rotation of the other pins.
With a handwheel or other appropriate means, the user can drive the gears which rotate the pivoting elements. Advantageously, the gears are conformed so as to reduce the transmission ratio and thus diminish the force of the user to rotate the pivoting elements.
Advantageously, it is also possible, by rotating one single leg, to tilt all of the other legs and in this manner vary the height of the work surface. Moreover, the legs can be tilted according to a wide (substantially infinite) number of configurations, not limited as with the table described in US-A-3,738,286 .
The aspects and advantages of the present invention will be more evident from the following description, given as merely exemplifying, with reference to the attached drawings in which:

Figure 1 is a schematic lateral view of a table according to the invention;
Figure 2 is a top axonometric view of the tilt adjustment mechanism of the legs of the table of Figure 1;
Figure 3 is a bottom axonometric view of the mechanism of figure 2;
Figure 4 is a top axonometric view of the mechanism of Figure 2, without some components so to better illustrate its structure;
Figure 5 is a bottom axonometric view of the mechanism of Figure 4;
Figure 6 is a lateral view of a gear of the mechanism of figure 2.

The following description, referred to the aforesaid drawings, regards a table 10 with three legs 21, 31, 41, it being understood that the support structure can also comprise two or more than three legs.
The table 10 according to the invention comprises a surface 12 supported by the three legs 21, 31, 41 with perimeter of triangular form with curvilinear sides. The leg portions corresponding to the three vertices of the triangle are respectively a support point of the leg on the ground, a point of contact and support between leg and table, and a connection point to a mechanism 20, illustrated in figure 1 contained within a spherical cover. The three legs 21, 31, 41 are therefore connected to each other by means of the mechanism 20 and are each rotatable around its own horizontal axis.
The mechanism 20, illustrated in figures 2, 3, comprises a carrier structure formed by a disc 52 and a plate 54, parallel and connected to each other by four spacer columns 56.
On one axis 18, perpendicular and rotatable with respect to the disc 52 and to the plate 54, a bevel gear wheel 14 and a gear wheel 70 are rigidly mounted.
The bevel gear wheel 14 engages three bevel pinions 24, 34 (in figures 2 and 4 only two pinions are visible and indicated) whose shafts 124, 134 are rotatably mounted on respective supports 28, 38 rigidly fixed on the face of the disc 52 turned towards the plate 54. The three bevel pinions 24, 34 and the respective shafts have axis parallel to the disc 52 and are arranged in rotation symmetry with respect to the axis 18 (120° angles are formed between the shafts).
Each shaft of the three pinions 24, 34 in engaged in a respective joint 27, 37 with adjustable tightening. In turn, a pin 36 is coupled on each joint 27, 37 (in figure 2 only one pin is visible), pin 36 coaxial with the related shaft of the pinions 24, 34 (mounted on the same joint).
Each pin is rotatably mounted on a support 29, 39 and is integral with a fixing fork 22, 32, 42 arranged outside the edge of the disc 52. Each fixing fork 22, 32, 42 stably locks one portion (corresponding with one of three vertices) of a leg.
The shafts of the three pinions are integral by means of the joints 27, 37 to the respective pins of the forks, so that the same forks (and related legs) are all tilted at a same angle. Possible adjustments are possible by acting on the adjustable tightening joints 27, 37.
Due to the above-described gear complex, the legs of the table 10 rotate simultaneously, or rather the rotation of the bevel gear wheel 14 leads to a simultaneous rotation of the three pinions 24, 34 and consequently of the axis of the pin of each fork 22, 32, 42 integral with the respective leg 21, 31, 41.
As is visible in the figures 4, 5, the gear wheel 70 engages a second gear wheel 170 rigidly mounted on an axis 118. The number of teeth and the diameter of the gear wheel 170 are less than those of the gear wheel 70.
With reference to figures 3 and 5, a gear wheel 16 is mounted on the axis 118, gear wheel 16 arranged on the face of the disc 52 opposite that turned towards the plate 54 (the disc 52 is interposed between the gear wheel 16 and the second gar wheel 170). The number of teeth and diameter of the gear wheel 170 are less than those of the gear wheel 16.
The gear wheel 16 engages a worm screw 62, mounted on two supports 64 fixed to the disc 52. One end 66 of the worm screw 62 is shaped with polygonal section so to form a male-female coupling with the bush 68 at one end of a handwheel 60 (bush with section equal to the end 66). Instead of the male-female coupling described above, other coupling systems known in the sector can in any case be used
By rotating the worm screw 62 with the handwheel 60, the gear wheel 16 rotates and, since it is rigidly pivoted on the axis 118, the second gear wheel 170 also turns. The second gear wheel 170, in turn, rotates the gear wheel 70, on which it engages, and consequently also the bevel wheel 14 rotates, it being rigidly mounted on the same axis 18 of the gear wheel 70. The gear wheel 14 rotates the pinions 24, 34, which, being connected to the forks 22, 32, 42, vary the tilt of the legs 22, 32, 42 and the height of the table 10 surface 12 from the ground
The structure of the gears (diameter and number of teeth of the gear wheel 16, of the second gear wheel 170, of the gear wheel 70 and of the bevel wheel 14) involves a reduction of the transmission ratio, so that the user's force for rotating the handwheel 60 is minimal.
Moreover, unless there are intentional interventions of the worm screw 62, the coupling of the gear wheel 16 with the worm screw 62 blocks the rotation of the gears formed by the gear wheel 14 and the position of the pinions 24, 34, maintaining the configuration of the table 10 according to the pre-selected tilt of the legs.
The table can comprise a number of legs which is greater than 3. The same form of the legs can be different from that of the described variant: for example, one leg can be a simple rod, locked by the corresponding fork (or other locking means).
Moreover, the simultaneous rotation of the pins connected to the legs (and the related tilt of the legs) can be obtained with transmission mechanisms which are different from that described, also using belts, pulleys or gear wheels which are diversely arranged
Analogously, variations are also possible of the mechanism driven by the user to rotate and lock the pins connected to the legs; for example, a worm screw can be coupled directly to a gear wheel (wheel 14 in the case of table 10) which engages the bevel wheels connected to the pins of the legs.
According to one variant of the invention, the mechanism for tilting the legs can comprise pinions rotating independently from each other (without mechanical interconnection). An adjustment mechanism of the rotation of each pinion permits rotating each leg by a different angle, so to be able to not only vary the height of the surface, but also tilt it according to the desired configuration.
According to a further variant of the invention, the support structure can comprise only two legs connected to each other and with adjustable tilt. At least one of the two legs comprises a base at its abutment end with the ground, such as for example a bar perpendicular to the leg.
A further variant of the invention provides that the support structure comprises a single leg connected in a tiltable manner by means of the same support structure to the surface to be supported. For example, the load-bearing structure of a table can be an articulated parallelogram in which an oblique side corresponds to a leg connected in an adjustable, tiltable manner with the support structure to the surface or with the side of abutment to the ground

Claims

Support structure with variable height for a surface (12) comprising at least two tiltable legs (21, 31, 41), and a support (52, 54, 56) to which the at least two legs (21, 31, 41) are pivoted by means of respective pivoting elements, characterised in that it comprises means (14, 24, 34) for the controlled rotation of each pivoting element by a desired angle.
Support structure according to claim 1, wherein the pivoting elements comprise mechanical interconnection means (14, 24, 34), so that with a rotation of one pivoting element there corresponds a rotation of the other pivoting elements.
Support structure according to claim 2, wherein each pivoting element comprises a pinion (24, 34) with respective pin (124, 134), each pinion (24, 34) being engaged on at least one gearwheel (14) mounted on a shaft (18).
Support structure according to claim 3, comprising adjustment means (16, 18, 62, 70, 118, 170) of the rotation of a pin (124, 134) of the pinions (24, 34).
Support structure according to claim 4, wherein the adjustment means comprise a system of gears (16, 18, 62, 70, 118, 170) which are mechanically connected to the gear wheel (14).
Support structure according to claim 5, wherein the system of gears comprises a worm screw (62) which engages the gearwheel (14).
Support structure according to claim 6, wherein the gear comprises a worm screw (62) which engages a gear wheel (16) mounted on a shaft (118) on which also a second gear wheel (170) is rigidly mounted; the second gear wheel (170) being engaged on a gear wheel (70) having shaft (18) in common with the gear wheel (14).
Support structure according to claim 7, wherein the diameter and number of teeth of the second gear wheel (170) are less than those of the gear wheel (70) on which it engages.
Support structure according to claim 7, wherein the diameter and number of teeth of the second gear wheel (170) are less with respect to those of the gear wheel (16) mounted on the same shaft (118).
Support structure according to claims 6 or 7, wherein the adjustment means comprise a handwheel (60), which can be engaged in a removable manner on the worm screw (62).
Support structure according to one of the preceding claims, wherein the pins of the pinion (24, 34) have rotation axes lying on the same plane.
Support structure according to one of the preceding claims, wherein the pins of the pinions comprise fixing forks (22, 32, 42) to the legs.
Support structure according to claim 11, wherein the legs are of triangular form with one vertex integral with the respective fork (22, 32, 42).
Support structure according to one of the preceding claims, wherein the support is covered by a spherical cover.
Support structure according to one of the preceding claims, wherein the legs are at least three.
Support structure with variable height comprising:
- a support for a surface,

- at least one tiltable leg connected to the support,
characterised in that it comprises means for the controlled rotation of the at least one leg with respect to the support by a desired angle.
Table (10) comprising at least one support structure according to one of the preceding claims.