Improved extensible leg

Abstract: An extensible leg for tables comprises, in combination: a tube (11) which can be translated inside the interior of a hollow space (25) defined by an external sleeve (16) and an internal rod (14). On said rod (14) an end of said tube (11) slides, the opposite end of which tube (11) is designed to be fastened to the tabletop.

Description: The present invention relates to an improved extensible leg designed in particular, but not exclusively, for tables. As those skilled in the art are well aware of, under certain circumstances, it would be highly desirable if one had available tables and/or similar working or supporting tops, of which the height (i.e., distance from floor) can be adjusted by the user, with extreme ease and precision, according to the actual requirements, in particular of ergonomic character. For example, it is recommended that the level from the floor to the top of a table used by a child is varied as a function of the child's growth in tallness, in order to prevent as far as possible that child's backbone may undergo malformations. For that purpose, the length of table legs should be adjustable within a very wide range, for example of a round 15-20 cm, also on considering the average tallness of different populations. The purpose of the present invention therefore is of fulfilling the above cited requirements by providing a leg for tables which, besides being easily extensible, additionally displays a sturdy structure and a valuable aesthetical appearance. The above purpose is achieved by an extensible leg as recited in the appended claim 1. Further embodiments are addressed in the dependent claims. The structural and functional characteristics of the present invention and its advantages over the prior art will be evident from the following disclosure, made by referring to the accompanying drawings, which show an exemplifying embodiment of extensible leg realized according to the teachings of the same invention. In the drawings: Figure 1 shows an elevation view illustrating an extensible leg realized according to the teachings of the present invention; Figure 2 is a longitudinal sectional view of the leg of Figure 1 in an extended position; Figure 3 is a longitudinal sectional view of the leg of Figure 1 in its completely lowered, i.e., retracted, position; and Figures 4 and 5 are sectional views, on an enlarged scale, of details respectively illustrating the leg in an extended position (Figure 2) and in its completely lowered, i.e., retracted, position (Figure 3). Referring to the drawings, the extensible leg according to the present invention is generally indicated with (10) and is structurally formed by a tube (11) to an end of which a sleeve (12) is applied which is provided with an internal screw-thread (13) (Figures 4 and 5). Said sleeve (12) is integral with said tube (11). On said sleeve (12) a rod (14), provided with a screw-thread (15), is engaged; said rod (14) is integral with an outer control sleeve (16), for example of conical shape, which, at one of its ends, is provided with a ring-like collar (29) closed around tube (11). The internal rod (14) and the external sleeve (16) are constrained to each other by means of a coupling means (17) constituted by a base (18) from which two concentric cylindrical portions (19) (the innermost portion) and (20) (the outermost portion), respectively, extend upwards. The portion (19) is higher and is made integral with said rod (14) by means of a coupling of groove-rib type (21), (22). The portion (20) is shorter, and is provided with grooves (23) inside which inner ribs (24) of the external sleeve (16) get engaged. In that way, the sleeve (16) is made integral with the extending cylindrical portion (20) of the coupling means (17). Therefore, it will be evident how the internal rod (14) and the external sleeve (16) are integrally coupled to one another for rotation by the coupling means (17), and that inside the hollow space (25) defined between them the tube (11) can move, i.e., translate, which tube (11), at its opposite end relatively to said sleeve (16) is fastened, by means of a coupling means (26) of known type, to a tabletop (27) (Figures 3 and 4). The reference numeral (28) indicates a scale applied to tube (11) from which the user can read the leg extension extent (Figure 1). The leg can be easily adjusted in height by rotating, in either directions, the external sleeve (16) -- consequently, the internal rod (14) -- which will cause the tube (11), which is linked to the rod (14) through the screw-threaded sleeve (12), to translate upwards or downwards. It should be observed that in the extensible leg according to the present invention, the extension mechanism is of relatively cheap structure and extremely easy to assemble. Additionally to the above, said extension mechanism is completely hindered to sight by the presence of the external sleeve (16) which, however, is not just a simple aesthetical component, but also performs a structural task, contributing to increase the strength of the overall mechanism. In fact, the components (12), (14), (17), (16) and (11) are all stably concatenated, as it is clearly displayed in the drawings. The purpose recited in disclosure preamble is thus achieved.

Claims: Extensible leg for tables characterized in that it comprises, in combination: a tube (11) which can be axially translated inside the interior of a hollow space (25) defined by an external sleeve (16) and an internal rod (14) on which the lower end of said tube (11) is movable upwards and downwards, with the opposite, upper end of said tube (11) being designed to be fastened to the tabletop, wherein said rod (14) is integral with said sleeve (16) which is a control sleeve for adjusting the length of the leg, and wherein said rod (14) and the lower end of said tube (11) are provided with complementary screw-threads (15, 13). Leg according to claim 1, characterized in that a sleeve (12) is integral with said lower end of said tube (11), with said sleeve (12) being provided with an internal screw-thread (13) on which said screw-threaded rod (14) gets inmeshed. Leg according to claim 2, characterized in that said internal rod (14) and the external sleeve (16) are coupled to each other by means of a coupling means (17) constituted by a base (18) from which two concentric cylindrical portions (19), (20), an innermost portion (19) and an outermost portion (20), respectively EXTEND, with the portion (19) being higher and being made integral with said rod (14) by means of a coupling of groove-rib type (21), (22), and the portion (20) being shorter and being provided with grooves (23) inside which inner ribs (24) of said sleeve (16) get engaged. Leg according to claim 1, characterized in that said sleeve (16) is provided at one of its ends with a ring-like collar (29) closed around tube (11).

Inventors: CATTANEO CARLO, CATTANEO, CARLO
Applicants: LEONARDO SRL, LEONARDO S.R.L.
Application year: 1996
Main classification: A47B9
IPC codes: A47B9