[0001] The present invention relates to a chair.
[0002] It is known that in the field of the manufacture of chairs (as well as armchairs
and the like) it is particularly important to combine excellent strength characteristics
with the possibility of good constructive flexibility in terms of low costs, aesthetics/styling,
and ergonomic design.
[0003] On the basis of these requirements, a chair has been provided in which the seat and
backrest are produced individually by overmolding plastics material on supporting
elements made of metallic material.
[0004] The components are provided in the finished state simply with a single process, which
is the molding process, and are assembled simply by interlocking.
[0005] This ensures considerable strength together with low weight and flexibility of shape
in manufacturing.
[0006] Moreover, the structure allows the components to be packed in the disassembled state,
with a great reduction in overall dimensions for storage and transport.
[0007] This chair has been quite successful commercially thanks to the advantages cited
above, but has still shown that further evolutions of the basic technical concept
of overmolding plastics materials on the metallic supporting elements are possible,
such evolutions being aimed at optimizing the structure as a function of the mechanical
strength characteristics required for the various regions and of the optimization
of the production cycle in order to obtain the finished product without the need for
finishing processes after molding.
[0008] The aim of the present invention is to provide a chair that by utilizing the technique
of overmolding on metallic supporting elements has characteristics of mechanical strength
that are differentiated by regions, such as adequate rigidity at the legs and flexibility
at the backrest.
[0009] Within this aim, an object of the present invention is to provide a chair whose structure
is substantially weatherproof and is therefore suitable both for indoor use and for
outdoor use or in any case in environments with a high chemical aggression factor.
[0010] Another object of the present invention is to provide a chair whose structure allows
a considerable reduction of the thicknesses of the various regions, with consequent
savings of material.
[0011] Another object of the present invention is to provide a chair that can be obtained
in the finished state simply by means of the molding process.
[0012] Another object of the present invention is to provide a chair that can be manufactured
with known equipment and technologies.
[0013] This aim and these and other objects that will become better apparent hereinafter
are achieved by a chair having a structure provided with internal supporting inserts
made of metallic material, characterized in that said internal supporting inserts
made of metallic material are mutually connected so as to form a frame that is completed
by internal inserts made of plastics material, the entire assembly being enclosed
in an overmolded cladding produced by injecting thermoplastic material, which also
forms the contact portions of the seat and backrest.
[0014] Conveniently, the internal supporting inserts made of metallic material are combined
and cooperate with internal inserts made of plastics material that are mutually differentiated
by regions in their mechanical strength features, the entire assembly being enclosed
in an overmolded cladding made of plastics material, which also forms the contact
portions of the seat and backrest.
[0015] Further characteristics and advantages of the present invention will become better
apparent from the description of two embodiments thereof, illustrated by way of non-limitative
example in the accompanying drawings, wherein:
Figure 1 is an external front view of a chair according to the invention, assembled
in its two components;
Figure 2 is a partially sectional side view of the chair of Figure 1 in the assembled
condition;
Figure 3 is a sectional side view of the chair of Figure 1 in the disassembled condition;
Figure 4 is a sectional view, taken along a substantially horizontal plane, of the
chair of Figure 1 in the assembled condition;
Figure 5 is a sectional view of a detail of a front leg;
Figure 6 is a sectional view of a detail of a backrest and of a rear leg;
Figure 7 is an enlarged-scale sectional view of the region of mutual coupling of the
two components of the chair of Figure 1;
Figure 8 is an enlarged-scale sectional view, taken along a plane that is perpendicular
to the plane of Figure 6, of the region of mutual coupling of the two components of
the chair of Figure 1;
Figure 9 is an exploded perspective view of a frame according to the invention, completed
with inserts made of plastics material;
Figure 10 is a perspective view of a chair according to the invention;
Figure 11 is a perspective view of a detail of a leg according to the invention.
[0016] With reference to the figures, a chair having the structure according to the invention
is generally designated by the reference numeral 10 in a first embodiment.
[0017] The chair 10 is composed of two components, which are mutually reversibly associated
by interlocking as described hereinafter.
[0018] A first component 11 comprises a seat 12 and two front legs 13, and a second component
14 comprises a backrest 15 and two rear legs 16.
[0019] According to the invention, the two components 11 and 14 are each formed by injection
overmolding of a cladding, respectively designated by the reference numerals 17 and
18, made of thermoplastic material, such as for example polypropylene, over tubular
internal supporting inserts made of metallic material that will be described in greater
detail hereinafter.
[0020] In particular, the first component 11 comprises, in this case, a tubular insert 19
made of shaped steel for the perimeter of the seat 12 and tubular steel inserts 20
for the front legs 13, which are closed at their lower free ends by inserts made of
plastics material 21 (so as to prevent the cladding 17 from entering the inserts 20
during molding).
[0021] The free ends 22 of the tubular insert 19 (which are arranged at the rear) are instead
arranged so as to remain open in order to constitute the receptacles for the insertion
of tangs 23 that protrude from the second component 14 of the chair 10.
[0022] As regards the second component 14,'it comprises in this case tubular inserts 24
made of steel for the rear legs 16, which are closed at their lower free ends by inserts
25 made of plastics (so as to prevent the cladding 18 from penetrating in the inserts
24 during molding).
[0023] Hole plugging inserts 26 made of plastics are instead inserted in the upper ends
of the tubular inserts 24 and also extend inside the backrest 15.
[0024] Elongated inserts 27 made of plastics, such as for example nylon, are overmolded
on these inserts 26, are shaped so as to taper toward their ends along the respective
sides 28 of the backrest 15, and are also embedded in the cladding 18.
[0025] The inserts 27 conveniently have different mechanical strength characteristics with
respect to the metallic inserts 24, giving elasticity to the backrest 15, which can
thus be flexed backward (like a cantilevered leaf spring) in order to adapt to the
movements of the back of the user.
[0026] The backrest 15 has, between the upper ends of the rear legs 16, a straight metallic
insert 29 from which, adjacent to the ends, perpendicular tabs 30 protrude which constitute
the cores of the tangs 23.
[0027] The insert 29, with the tabs 30, is enclosed by an overmolded cladding 31 (insert)
made of plastics, such as for example nylon, which except for the regions of the tabs
30 is further enclosed by the cladding 18.
[0028] The internal metallic inserts designated by the reference numerals 19, 20, 24 and
29 constitute as a whole a frame 50 that is completed by the plastic inserts 21, 25,
26, 27 and 31.
[0029] Moreover, the claddings 31 and 18 form tabs 32 that are arranged laterally adjacent
to the tangs 23 for resting against the rear edge 33 of the seat 12.
[0030] The cladding 31 in the region of the tabs 30 avoids metal-on-metal contact between
the tangs 23 and the respective receptacles formed by the ends of the tubular insert
19 and allows a better interlocking between the parts by way of the adaptability of
the plastic material.
[0031] A second embodiment of a chair having the structure according to the invention is
designated by the reference numeral 110 in Figures 9 to 11.
[0032] The supporting internal inserts made of metallic material, here designated respectively
by the reference numerals 119, 120, 124 and 129, are mutually connected so as to form
a single supporting insert 150 to be inserted in a mold.
[0033] As in the first embodiment, a first insert 119 forms the seat 112, second inserts
120 form the front legs 113, third inserts 124 form the rear legs 116, and a fourth
insert 129 completes the seat 112, connecting the inserts 124 for the rear legs.
[0034] Hole plugging inserts 126 made of plastics material are inserted in the upper free
ends 151 of the single metallic supporting insert 150 and, in the same manner described
for the first embodiment of the chair 10 according to the invention, also extend within
the corresponding backrest 115, improving its backward flexural elasticity.
[0035] External inserts 161 made of plastics for resting on the ground are instead inserted
in the lower free ends 152 of the single supporting insert 150.
[0036] Such internal inserts made of metallic material 119, 120, 124 and 129 are connected
by welding.
[0037] The single metallic supporting insert 150 and the internal hole plugging inserts
126 made of plastics are enclosed in a single overmolded cladding 117, which also
forms the contact portions of the seat 112 and of the backrest 115, so as to form
a monolithic chair.
[0038] In practice it has been found that the present invention has achieved the intended
aim and objects.
[0039] The chair in fact has a structure provided with internal supporting inserts 19, 20,
24, 29, 119, 120, 124, 129 that are mutually connected so as to form a frame 50, 150,
which is completed by internal inserts 21, 25, 26, 27, 31, 126 made of plastics.
[0040] Moreover, advantageously, in a first embodiment the chair has a structure provided
with internal supporting inserts 19, 20, 24, 29 made of metallic material, which are
combined and cooperate with internal inserts 21, 25, 26, 27, 31 made of plastics,
which are mutually differentiated by regions in their mechanical strength features.
[0041] Therefore, by utilizing the technique of overmolding over metallic supporting elements,
the chair has mechanical strength characteristics that are differentiated by regions,
such as adequate rigidity at the legs and flexibility at the backrest.
[0042] Further, in said first embodiment the components are provided in the finished state
simply with a single process, which is the molding process, and are simply assembled
by interlocking.
[0043] This ensures considerable strength together with low weight and flexibility of configuration
and manufacture.
[0044] Further, the structure described and exemplified with the first embodiment allows
pluralities of the two components to be mutually packed, in the disassembled state
prior to final assembly, with a considerable reduction of overall dimensions for storage
and transport.
[0045] Advantageously, the second embodiment instead allows to obtain a monolithic chair
simply and cheaply, by inserting in a mold a single metallic insert and by means of
a subsequent single injection overmolding operation.
[0046] The invention thus conceived is susceptible of numerous modifications and variations,
all of which are within the scope of the appended claims.
[0047] The materials, so long as they are compatible with the contingent use, as well as
the dimensions, may be any according to requirements.
[0048] The disclosures in Italian Patent Application No. PD2002A000177, from which this
application claims priority, are incorporated herein by reference.
[0049] Where technical features mentioned in any claim are followed by reference signs,
those reference signs have been included for the sole purpose of increasing the intelligibility
of the claims and accordingly such reference signs do not have any limiting effect
on the interpretation of each element identified by way of example by such reference
signs.
1. A chair with a structure provided with internal supporting inserts (19, 20, 24, 29)
made of metallic material, characterized in that said internal supporting inserts (19, 20, 24, 29, 119, 120, 124, 129) made of metallic
material are mutually connected so as to form a frame (50, 150) that is completed
by internal inserts (21, 25, 26, 27, 31, 126) made of plastics material, the entire
assembly being enclosed in an overmolded cladding (17, 18, 117) produced by injecting
thermoplastic material, which also forms the contact portions of the seat (12, 112)
and backrest (15, 115).
2. The chair provided with the structure according to claim 1, characterized in that said internal supporting inserts (19, 20, 24, 29) made of metallic material are combined
and cooperate with said internal inserts (21, 25, 26, 27, 31) made of plastics material,
which are mutually differentiated by regions in their mechanical strength features,
the entire assembly being enclosed by an overmolded cladding (17, 18) made of plastics
material, which also forms the contact portions of the seat (12) and backrest (15).
3. The chair according to claims 1 and 2, characterized in that it is composed of two components that are mutually associated reversibly by interlocking,
a first component (11) comprising the seat (12) and two front legs (13) and a second
component (14) comprising the backrest (15) and the rear legs (16).
4. The chair provided with the structure according to one or more of claims 1 to 3, characterized in that said two components (11, 14) are each formed by overmolding a cladding (17, 18) made
of plastics material over internal supporting inserts (19, 20, 24, 29) made of metallic
material combined with internal inserts (21, 25, 26, 27, 31) made of plastics material.
5. The chair provided with the structure according to one or more of the preceding claims,
characterized in that a first component (11) comprises a tubular insert (19) made of contoured metal for
the perimeter of the seat (12) and tubular inserts (20) made of metal for said front
legs (13) which are closed at their lower free ends by inserts (21) made of plastics
material.
6. The chair provided with the structure according to one or more of the preceding claims,
characterized in that the free ends (22) of said metallic insert (19) for the perimeter of the seat (12)
that are arranged at the rear are arranged so as to remain open in order to constitute
the receptacles for the insertion of tangs (23) that protrude from said second component
(14) of the chair (10).
7. The chair provided with the structure according to one or more of the preceding claims,
characterized in that said second component (14) comprises tubular inserts (24) made of metal for the rear
legs (16), which are closed at their lower free ends by inserts made of plastics material
(25).
8. The chair provided with the structure according to one or more of the preceding claims,
characterized in that hole plugging inserts (26) made of plastics are inserted in the upper ends of said
tubular inserts (24) of said second component and also extend inside the backrest
(15).
9. The chair provided with the structure according to one or more of the preceding claims,
characterized in that elongated inserts (27) made of plastics material are overmolded on said hole plugging
inserts (26) of said metallic tubular inserts (24), are shaped so as to taper toward
their ends along the respective sides (28) of said backrest (15), and are also embedded
in said cladding (18) thereof, said elongated inserts (27) giving elasticity to said
backrest (15).
10. The chair provided with the structure according to one or more of the preceding claims,
characterized in that said backrest (15) has, between the upper ends of the rear legs (16), a metallic
insert (29) from which perpendicular tabs (30) protrude adjacent to the ends, said
tabs constituting the cores of said tangs (23), said insert (29) with said tabs (30)
being enclosed by an overmolded cladding (31) made of plastics material which, except
for the regions of the tabs (30), is further enclosed by said cladding (18).
11. The chair provided with the structure according to one or more of the preceding claims,
characterized in that said claddings (31, 18) of said backrest (15) form tabs (32) that are laterally adjacent
to the tangs (23) for contact against a rear edge (33) of said seat (12).
12. The chair provided with the structure according to claim 1, characterized in that said internal supporting inserts (119, 120, 124, 129) made of metallic material are
mutually connected so as to form a single metallic supporting insert (150) to be inserted
in a mold.
13. The chair provided with the structure according to claims 1 and 12, characterized in that hole plugging inserts (126) made of plastics material are inserted in the upper free
ends (151) of said single metallic supporting insert (150) and also extend inside
the backrest (115).
14. The chair provided with the structure according to claims 1, 12 and 13, characterized in that external inserts (161) made of plastics for resting on the ground are inserted in
the lower free ends (152) of said single metallic supporting insert (150).
15. The chair provided with the structure according to claims 1 and 12 to 14, characterized in that said internal supporting inserts (119, 120, 124, 129) made of metallic material are
connected by welding.
16. The chair provided with the structure according to claims 12 to 15, characterized in that said single metallic supporting insert (150) and said internal hole plugging inserts
(126) made of plastics material are enclosed in a single overmolded cladding (117),
which also forms the contact portions of the seat (112) and the backrest (115), forming
a monolithic chair.