GB1575962A - Tables and a process of making tables - Google Patents

Description

(54) IMPROVEMENTS IN OR RELATING TO TABLES AND A PROCESS OF MAKING TABLES (71) We, KARTELL S.p.A., an Italian body corporate, of Via delle Industrie, 20 082 Noviglio, Milan, Italy, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:4 This invention relates to a process for the production of a table for domestic use and to a table so produced.

In the production of tables for domestic use it is known to use mainly plastics and/or metal materials which, as is well known, are much more resistant than wood to external influences. At present, tables for domestic use in general, and in particular those used outdoors, usually comprise a top formed by a sheet of chipboard on to which is glued a sheet of laminated plastics. This composite panel is mounted in a frame, generally made of metal or plastics material, the frame having integral lower attachment means for supporting legs.

As a result of the numerous separate parts used for the manufacture of such tables, the construction and assembly stages thereof involve high production and labour costs which add considerably to the cost of the finished product.

In such tables, in addition to the abovedescribed economic disadvantage, there are also disadvantages of a functional nature, one of the most serious of which lies in the fact that when the panel top is exposed to the influence of a heat source, for example the rays of the sun, mechanical stress is produced at the level of the contact surface between the plastics laminate and the sheet of chipboard, as result of the different coefficients of expansion of the two materials. Moreover, the ingress of moisture through any gap which may be present between said frame and the plastics laminate can cause an increase in volume of the sheet of chipboard and give rise to further mechanical stress mainly at the edge of the panel. Accordingly, the combined action of the sun and atplos- pheric humidity generally brings aboutin such tables the detachment and lifting of the periphery of the plastics laminate from the underlying sheet of chipboard.

Finally, in known tables it is relatively easy for both dust and foreign bodies to penetrate into any gap which may be present between the frame and the laminate, thus often making cleaning of the table rather difficult and ineffective.

According to the invention there is provided a process for the production of a table, particularly for domestic use and of the type comprising a panel, a frame surrounding the periphery of said panel and supporting legs each connected to a lower face of said panel by means of a respective connecting member, characterised in that the process comprises the step of producing said frame and said connecting members in a single piece of plastics material by moulding, the laterial face of said panel being used to define part of the surface of a mould cavity for said plastics material and said mould cavity being formed inside a mould detachably connected to the outer periphery of said panel.

The invention also provides a table, in particular for domestic use, produced by a process as described above, characterised in that said panel comprises a sheet of chipboard material, the top and bottom faces of which are each covered with a layer of plastics laminate, said panel being provided, in its lateral faces, with a rebate engaged by a corresponding rib projecting from an inner face of said frame.

A specific embodiment of the invention will now be described by way of example, with reference to the accompanying drawings in which: Figure 1 is an underneath perspective view, partly exploded and with some parts omitted for clarity, of a table produced in accordance with the present invention; Figure 2 is an under plan view of a detail of the table illustrated in Figure 1; Figure 3 is a top plane view of the table illustrated in Figure 1; Figure 4 is a section taken on the line IV-IV in Figure 2; Figure 5 is a section taken on the line V-V in Figure 2; Figure 6 is a section taken on the line VI-VI in Figure 2; Figure 7 is a section taken along the line VII-VII in Figure 4; and Figure 8 illustrates, in section, an assembly for the production of a detail of Figure 1.

Figures 1 to 7 show a table 10 having a panel top 1, of substantially square shape and comprising a supporting sheet 2 made, preferably, of chipboard and whose top and bottom faces are each covered with a layer of laminated plastics, respectively designated 3 and 4.

The panel 1 has a lateral face 5 comprising upper and lower portions 6 and 7 formed by the lateral faces of the top and bottom layers 3 and 4 respectively, and a central portion 8 formed by the lateral face of the supporting sheet 2 and having a groove 9.

The panel 1 is surrounded by a frame 12 which, in correspondence with each of the four corners of the panel 1, has underneath a lower supporting and stiffening rib 13 for said support surface, one rib projecting inwards along the diagonal of the panel 1, and extending from each said corner.

Futhermore, the frame 12 has at each of said corners, a connecting member 14 designed to engage the upper end of a leg 15 (for supporting the panel 1) by means of its own tubular attachment 16, whose axis is substantially perpendicular to said panel, and extends downwardly from the frame 12. Each leg 15 is held fast in the tubular attachment 16 by a detachable locking means. The frame 12, the ribs 13 and the connecting member 14 are integral with one another and comprise a single piece of plastics material, preferably expanded polyurethane.

In more detail and referring to Figure 6, the frame 12 has an upper face 17 situated in the same plane as the upper layer 3 of the panel 1, an outer vertical face 18 and a lower face 19 which connects the outer face 18 with the bottom layer 4 of the panel 1, while covering a narrow lateral zone thereof. In addition, the frame 12 is arranged internally in contact with the entire lateral face 5 (Figure 4) of the panel 1, with which it provides positive engagement by means of rib 20 which engages with the corresponding rebate 9.

With particular reference to Figures 1 and 4, each attachment 16 receives a tubular metal sleeve 21, one portion of which is left exposed by an axial slot 22 machined along the attachment 16 and positioned facing its associated rib 13-.

As shown in Figure 7, each slot 22 receives a shaped metal locking plate 23 having an internally threaded hole through which passes a screw 24 which can be adjusted from the exterior. The screw engages a hole 25 (Figure 1) provided in the inserted leg 15, so as to lock said leg on to its attachment 16.

Each leg 15 is tubular in shape and in its upper part has an internal diameter practically equal to the outer diameter of the related attachment 16. The lower part of each leg 15 is adapted to receive a support foot 26 (Figure 1).

In Figure 8 there is shown in section a part of a mould 30 detachably connected to the panel 1 and required for making, in a single piece, the frame 12, the ribs 13 and the connecting member 14 with the related attachments 16.

For this purpose, the mould 30 comprises two half-shells 31 and 32 which enclose the lateral faces 5 of the panel 1 and cooperate therewith so as to define a mould cavity 33.

In particular, the half-shells 31 and 32 have two peripheral projections 34 and 35 designated to cooperate as a seal with a related face of the panel 1, and which are arranged so as to impart to the panel a uniformly distributed bending couple, with the aim of exerting a localised pressure on the layers 3 and 4 along the periphery of said panel when this latter is clamped between the half-shells 31 and 32.

In addition, the mould 30 has, one for each of the four corners of the panel 1, a substantially cylindrical cavity and a substantially radial cavity (not shown), which are designed to define, respectively, each attachment 16 of the connecting member 14 and each lower supporting and stiffening rib 13 for the panel 1.

Finally, a thrust member (not shown) carried by the mould 30 through the half-shell 31 is designed to cooperate centrally with the panel 1, so as to counter the aforementioned bending couple and increase the contact pressure between the layers 3 and 4 and the respective projections 34 and 35 in order to prevent any escape of plastics material from the cavity 33 during the injection moulding operation.

The production in a single piece of moulded plastics material of the frame 12, ribs 13 and attachments 16 directly on the outer edge of the panel 1 offers considerable advantages with respect to the methods described previously and used hitherto for the manufacture of tables of the type described with reference to Figures 1 to 7. In fact, the process described with reference to Figure 8, in addition to providing the table with a relatively compact structure and enabling the table itself to be assembled in a number of operations which are greatly reduced in relation to that involved in the known assembly methods, brings about an intimate physical or mechanical connection between the frame 12 and the layers 3 and 4.

To this end, it is necessary to note that during the moulding stage the material fed at relatively high pressure and temperature into the cavity 33 tends to bond itself physically to the material forming the layers 3 and 4, and that this physical bond is reinforced by the compression forces which are generated, during the contraction of the moulded material, between the frame 12 and the panel 1. The physical or mechanical bond mentioned above brings about complete insulation of the sheet 2 from external influences and completely eliminates any possibility of a crevice being formed between the frame 12 and the panel 1.

WHAT WE CLAIM IS: 1. A process for the production of a table, particularly for domestic use and of the type comprising a panel, a frame surrounding the periphery of said panel and supporting legs each connected to a lower face of said panel by means of a respective connecting member, characterised in that the process comprises the step of producing said frame and said connecting members in a single piece of plastics material by moulding, the lateral faces of said panel being used to define part of the surface of a mould cavity for said plastics material and said mould cavity being formed inside a mould detachably connected to the outer periphery of said panel.

2. A process according to claim 1, characterised in that said plastics material is expanded polyurethane.

3. A process according to claim 1 or claim 2 characterised in that said mould comprises two half-shells designed to be clamped against one another with the interposition of said panel, so as to define the mould cavity, each of said half-shells having a projection designed to cooperate as a seal with a respective face of the panel so as to impart to the panel, conjointly with the projection of the other half-shell, a bending couple uniformly distributed along the periphery of said panel, and one of said half-shells being provided with thrust means designed to cooperate centrally with said panel so as to impart thereto an axial thrust intended to counter said bending couple.

4. A process according to any one of the preceding claims, characterised in that said mould cavity comprises, corresponding to each of said connecting members, a substantially radial cavity designed to define a lower supporting and stiffening rib for said panel.

5. A table, in particular for domestic use, produced by a process according to any one of the preceding claims, characterised in that said panel comprises a sheet of chipboard material, the top and bottom faces of which are each covered with a layer of plastics laminate, said panel being provided, in its lateral faces, with a rebate engaged by a corresponding rib projecting from an inner face of said frame.

6. A table according to claim 5, and including connecting members integral with said frame, each comprising a tubular attachment, whose axis is substantially perpendicular to said panel, and extends downwards from said frame, each supporting leg being tubular and being fitted into its respective tubular attachment with the interposition of detachable locking means.

7. A table according to claim 6, characterised in that said each detachable locking means comprises a tubular metal sleeve fitted inside each tubular attachment, a metal plate arranged between the outer surface of said metal sleeve and inner surface of the respective leg in registration with an axial slot provided along said tubular attachment, and a screw which can be adjusted from the exterior and which passes through a radial hole machined in said leg, and a threaded hole machined through said plate.

8. A process for the production of a table substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.

9. A table substantially as hereinbefore described with reference to and as illustrated in Figures 1 to 7 of the accompanying drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (9)

**WARNING** start of CLMS field may overlap end of DESC **. number of operations which are greatly reduced in relation to that involved in the known assembly methods, brings about an intimate physical or mechanical connection between the frame 12 and the layers 3 and 4. To this end, it is necessary to note that during the moulding stage the material fed at relatively high pressure and temperature into the cavity 33 tends to bond itself physically to the material forming the layers 3 and 4, and that this physical bond is reinforced by the compression forces which are generated, during the contraction of the moulded material, between the frame 12 and the panel 1. The physical or mechanical bond mentioned above brings about complete insulation of the sheet 2 from external influences and completely eliminates any possibility of a crevice being formed between the frame 12 and the panel 1. WHAT WE CLAIM IS:

1. A process for the production of a table, particularly for domestic use and of the type comprising a panel, a frame surrounding the periphery of said panel and supporting legs each connected to a lower face of said panel by means of a respective connecting member, characterised in that the process comprises the step of producing said frame and said connecting members in a single piece of plastics material by moulding, the lateral faces of said panel being used to define part of the surface of a mould cavity for said plastics material and said mould cavity being formed inside a mould detachably connected to the outer periphery of said panel.

2. A process according to claim 1, characterised in that said plastics material is expanded polyurethane.

3. A process according to claim 1 or claim 2 characterised in that said mould comprises two half-shells designed to be clamped against one another with the interposition of said panel, so as to define the mould cavity, each of said half-shells having a projection designed to cooperate as a seal with a respective face of the panel so as to impart to the panel, conjointly with the projection of the other half-shell, a bending couple uniformly distributed along the periphery of said panel, and one of said half-shells being provided with thrust means designed to cooperate centrally with said panel so as to impart thereto an axial thrust intended to counter said bending couple.

4. A process according to any one of the preceding claims, characterised in that said mould cavity comprises, corresponding to each of said connecting members, a substantially radial cavity designed to define a lower supporting and stiffening rib for said panel.

5. A table, in particular for domestic use, produced by a process according to any one of the preceding claims, characterised in that said panel comprises a sheet of chipboard material, the top and bottom faces of which are each covered with a layer of plastics laminate, said panel being provided, in its lateral faces, with a rebate engaged by a corresponding rib projecting from an inner face of said frame.

6. A table according to claim 5, and including connecting members integral with said frame, each comprising a tubular attachment, whose axis is substantially perpendicular to said panel, and extends downwards from said frame, each supporting leg being tubular and being fitted into its respective tubular attachment with the interposition of detachable locking means.

7. A table according to claim 6, characterised in that said each detachable locking means comprises a tubular metal sleeve fitted inside each tubular attachment, a metal plate arranged between the outer surface of said metal sleeve and inner surface of the respective leg in registration with an axial slot provided along said tubular attachment, and a screw which can be adjusted from the exterior and which passes through a radial hole machined in said leg, and a threaded hole machined through said plate.

8. A process for the production of a table substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.

9. A table substantially as hereinbefore described with reference to and as illustrated in Figures 1 to 7 of the accompanying drawings.