Pedestal with radial arms for chairs, furniture and the like, of variable dimensions

Abstract: A pedestal with radial arms for chairs, items of furniture and the like comprising a metal core formed of a cylindrical boss (10) to which may be attached a column capable of securing and supporting the seat or item of furniture, this boss having attached thereto one or a plurality of tubular metal arms (11) projecting radially therefrom, with a boss cover member (14) which can be inserted on the core having a central member (15) and one or a plurality of radial branches (16) corresponding to the arms of the metal core which are open at the base and extend over part of the length of the said arms, together with for each arm of the metal core a covering sheath (19) provided with means of attachment to the end of the arm which can be inserted in a longitudinal direction on the corresponding branch of the boss cover member (14) to a length depending on the extent of the arm.

Description: This invention relates to a pedestal with radial arms for chairs, furniture and the like, having variable dimensions. For items of furniture of various kinds, and in particular for chairs and office chairs and the like, pedestals having several, usually five, radial arms surrounding a central column which is connected at the top to the seat or chair are widely used. The radial arms of the pedestal extend radially for a sufficient distance to confer the required stability upon the chair. Chairs or office chairs of different sizes and characteristics, for example fixed seats or seats with articulated joints, require pedestals of different diameters in order to achieve equivalent stability characteristics. Pedestals of this kind are also used with the same or a different number of radial arms for items of furniture of various kinds, such as for example tables, occasional tables and the like, and individually appropriate pedestal dimensions are required for these purposes. A convenient form of constructing such pedestals provides for an internal core of metal which is intended to support the applied load and a cover constructed of moulded plastics material to provide the said core with the desired aesthetic characteristics. The cores of such pedestals may readily and economically be constructed from metal components which are cut to length and joined together by welding, while the cover, which is destined to be the visible part of the pedestal, has to be moulded to the intended size in a single piece or in several pieces. Thus in order to be able to construct pedestals of different dimensions it is necessary to have several different moulds, with an appreciable increase in costs. An example of this type of cover having fixed dimension is disclosed into GB 2.081.085. Also the fit between the welded core and the moulded portions may not be satisfactory, and may give rise to difficulties in assembly. There therefore arises the problem of providing a pedestal structure of the type specified which is economical to construct and can be used to provide different measurements without the provision of several moulds. These results are achieved by this invention, which provides a pedestal with radial arms for chairs, items of furniture and the like which comprises a metal core formed of a cylindrical boss to which may be attached a column capable of securing and supporting the seat or item of furniture, this boss having attached thereto one or a plurality of tubular metal arms projecting radially therefrom, being also provided with a covering sheath with means of attachment to the end of each arm of the metal core in which a boss cover member is provided which can be inserted on the core having a central member and one or a plurality of radial branches, corresponding to the arms of the metal core, said branches are open at the base and extend over part of the length of said arms, the covering sheath being inserted in a longitudinal direction on the corresponding branch of the boss cover member to a length depending on the extent of the arm. The sheath has a centering plug which can be inserted into a tubular arm and has a through hole which when assembled can be aligned with a corresponding hole placed close to the end of the tubular arm, and a fixing pin for a member supporting the pedestal on the ground can be inserted into these aligned holes. In greater detail, the covering sheath consists of a member of plastics material having an upside-down substantially U cross-section, with at one end the centering plug which can be inserted into the tubular arm and at the other end a tie member connecting the lower edges which is capable of coming into contact with the corresponding lower edges of the branches of the boss cover, one or a plurality of transverse ribs being provided within the sheath so as to centre the sheath about the boss in conjunction with the tie. The covering sheath has a window in its upper wall corresponding to the centering plug which can be shut by means of a corresponding cover so that the plug itself can be easily moulded. Further details will be revealed by the following description with reference to the appended drawings in which: Figure 1 shows an overall view of a chair with a pedestal according to the invention, Figure 2 shows a chair with pedestal of greater diameter, Figure 3 shows a portion of the end of a table with a pedestal according to the invention, Figure 4 shows the end portion of a table similar to that in Figure 3, but with a top of larger size and a wider pedestal, Figure 5 shows a detail of a pedestal according to the invention in cross-section along the plane V-V in Figure 6, Figure 6 shows the pedestal in plan view, in cross-section along the plane VI-VI in Figure 5, Figure 7 shows the sheath covering the arms of the pedestal viewed from above, Figure 8 shows a cross-section along the plane VIII-VIII in Figure 7, Figure 9 shows a cross-section along the plane IX-IX in Figure 7, Figure 10 shows a cross-section along the plane X-X in Figure 7, Figure 11 shows a cross-section along the plane XI-XI in Figure 6. As shown in Figure 1, the chair or office chair has a seat 1 and a back 2 supported by a column 3, which may suitably be of the telescopic type, attached at the lower end to a pedestal 4. Pedestal 4 commonly consists of a plurality of arms 5, normally five in number, projecting radially from a central boss 6 which is attached to column 3. The extension of arms 5, i.e. the maximum diameter of the pedestal, is determined by the required size of the base: For example, as illustrated in Figure 2, for a larger seat with a higher back,pedestal 4 will preferably be of larger diameter, i.e. will have longer arms 5. Similarly circular tables having a single pedestal with several radial arms of the most appropriate diameter may be constructed, or, as illustrated in Figure 3, rectangular or similar tables which have a pedestal 4 supporting a column 7 of the fixed type to which top 8 is connected may also be constructed; In this case pedestal 4 is of the type with two opposite arms 5, and in the case of tables having a larger top 8, as illustrated in Figure 4, arms 5 may be of greater length. In order to achieve the required size of pedestal, as illustrated in Figure 5 a central metal core 9 suitably constructed of tubular steel members cut to length and welded together comprising a central cylindrical boss 10 to which column 3 or 7 is connected and to which tubular arms 11 are attached is provided. Arms 11 are cut to a length corresponding to the desired size of the diameter of the pedestal and at their free ends in the part opposite to boss 10 have a hole 12 for the attachment of a pin bearing a supporting foot, castor or the like; the free ends of the arms are also appropriately provided with an oblique bevel 13. In order to provide the pedestal with the desired aesthetic characteristics a boss cover 14 of plastics material or the like capable of being fitted onto boss 10 by movement in an axial direction is provided. Boss cover 14 has a substantially cylindrical central portion 15 from which project a plurality of radial branches 16 corresponding in number and position to the arms 11 present. Branches 16 consist of members of a substantially U-shape which is open at the base, which can enclose the sides and tops of arms 11; two or more ribs 17 extending internally towards the arms ensure correct centering of branches 16 around arms 11 and thus of all boss cover 14 on core 9 of the pedestal. Two fins 18 placed at the end of each branch 16 capable of surrounding the lower face of the corresponding arm for a short distance, as better shown in Figure 11, as a result of the elastic deformability of the material covering the boss, ensure that the boss cover is firmly mounted on core 9. Covering sheaths 19 are then placed over branches 14 and arms 11 and these too are suitably constructed of plastics material and completely cover the visible surfaces of core 9 so as to provide the desired aesthetic appearance. Sheaths 19 consist of longitudinally extended members with a cross-section substantially in the form of an upside-down U, provided with internal ribs 20, 21 to enter into contact with arms 11 of core 9 and branches 16 of the boss cover respectively, centering the sheaths on these members. At its outer end each sheath also has a centering plug 22 which can be inserted within corresponding arm 11 with slight elastic deformation; a hole 23 in plug 22 is aligned with hole 12 in such a way that a pin passed through both holes prevents any possibility of the sheath coming off the arm. The pin which is to be inserted in holes 12, 23 is conveniently constructed as a pin supporting and securing a foot supporting the pedestal on the ground, a castor or the like, in accordance with aesthetic or practical requirements; hole 23 may of suitable shape and diameter corresponding to this pin so that for example the said pin may be secured by interference or by means of a thread. The pin, or the supporting member borne by it, is however designed to rest against arm 11, directly transmitting the applied load from the metal arm to the supporting member without the load acting on the members of the cover. Plug 22 is made integral with the end wall of sheath 24 through a plurality of ribs 25. The size of sheath 19 is fixed. It can however be adapted to different arm lengths of core 9 by telescopically varying the amount of overlap with branches 16 of the boss cover. The end of sheath 19 close to the boss cover provides for a tie 26 which joins together the bottom edges of the sheath itself, this tie being supported against the lower edge of branches 16, thus preventing the sheath from slipping upwards at these points, the sheath therefore becoming completely integral with the metal core. In order that sheath 19 may be constructed of moulded plastics material using a mould of simple shape, avoiding undercut portions, the end of the sheath facing the boss has a sufficient inclination, as illustrated in Figure 7, to project beyond the end of the upper wall 28 of the sheath; at the other end, corresponding to plug 22, wall 28 has a window 29 through which the upper surface of the plug can be moulded. A cover 30, which can be clipped into window 29, closes the said window, restoring continuity to the surface. It is therefore possible to obtain pedestals of different dimensions using the same moulded members and without having to provide several moulds of different dimensions, it only being necessary to construct core 9 to the desired size, and this, being constructed of welded metal components, may be constructed to be of any desired size without this having an adverse effect on costs. The lengths of the arms may also be different from each other in a given pedestal, for example for aesthetic reasons, only different dimensions of the arms 11 of the metal core being necessary for this. Pedestals for various purposes and having different numbers of arms may be constructed in an entirely similar way; for example pedestals with several radial arms combined with a fixed loadbearing column may be constructed for the central support of round or square tables, or pedestals may be constructed with only two opposing arms as illustrated in Figures 3, 4, or with a single arm to form a support for tables with an extended e.g. rectangular top using two identical pedestals, it being possible in every case to construct arms of different lengths using the same cover members.

Claims: A pedestal (4) with radial arms for chairs, items of furniture and the like which comprises a metal core (9) formed of a cylindrical boss (10) to which may be attached a column (3, 7) capable of securing and supporting the seat (1) or item of furniture, this boss (10) having attached thereto one or a plurality of tubular metal arms (11) projecting radially therefrom, being also provided with a covering sheath (19) with means of attachment to the end of each arm (11) of the metal core (9) characterized by the fact that a boss cover member (14) is provided which can be inserted on the core (9) having a central member (15) and one or a plurality of radial branches (16), corresponding to the arms (11) of the metal core (9), said branches (16) are open at the base and extend over a part of the length of said arms (11), the covering sheath (19) being inserted in a longitudinal direction on the corresponding branch (16) of the boss cover member (14) to a length depending on the extent of the arm. A pedestal (4) having radial arms according to claim 1, characterised in that the sheath (19) has a centering plug (22) which can be inserted into the tubular arm (11) fitted with a through hole (23) which can be aligned when assembled with a corresponding hole (12) placed close to the end of the tubular arm (11), and a pin fixing a member supporting the pedestal on the ground may be inserted in these aligned holes (12,23). A pedestal (4) with radial arms according to claim 1, characterised in that the covering sheath (19) consists of a member of plastics material having an upside down substantially U-shaped cross-section and at one end, a centering plug (22) which can be inserted into the tubular arm (11) and, at the other end, a tie member (26) connecting the lower edges which can come into contact with the corresponding lower edges of the branches (16) of the boss cover, (14) one or a plurality of transverse ribs (20,21) being provided internally within the sheath (19) so as to centre the sheath (19) on the boss cover (14) in conjunction with the tie member (26) A pedestal having radial arms according to claim 2, characterised in that the cover sheath (19) has a window (29) corresponding to the centering plug (22) in its upper wall which can be closed by means of a corresponding cover (30), through which the plug itself may easily be moulded.

Inventors: BORSANI PAOLO, BORSANI, PAOLO
Applicants: TECNO SPA, TECNO S.P.A. MOBILI E FORNITURE PER ARREDAMENTO
Application year: 1990
Main classification: A47C7
IPC codes: A47B91, A47C7