FIELD OF THE INVENTION
[0001] Embodiments described here concern a lighting apparatus used, preferably, but not
exclusively, in areas and/or environments in which the formation of an explosive atmosphere,
consisting of a mixture of air and flammable substances in the form of gas, vapors
or mist, can occasionally occur during normal production activities.
[0002] The present invention concerns both the composition and the production method of
said apparatus.
BACKGROUND OF THE INVENTION
[0003] Lighting apparatuses are known which comprise a containing body, provided with a
housing, in which a light source is located and possibly a compartment in which a
power supply and control unit is located.
[0004] The light source is suitable to generate a beam of light intended, for example, to
illuminate an internal or external environment, or to provide an alarm signal associated
with a malfunction of machinery inside a production plant.
[0005] Lighting apparatuses are known in which the containing body is made of metal material
and, in addition to the mechanical function of accommodating the various electronic/mechanical
components that make up the apparatus, it also performs a function of thermal dissipation
of the heat generated by the light source and by the power supply and control unit.
[0006] In other known lighting apparatuses, the containing body is made in two or more pieces
and of polymeric material. In this case, the heat dissipation function is performed
by a dissipation support of the light source made of metal material and mounted in
correspondence with the housing.
[0007] In particular, the category of such apparatuses includes, for example, spotlights,
projectors, illuminated fixtures and ceiling lights.
[0008] Currently, in the construction of lighting apparatuses that can be used in zones
classified according to the ATEX (ATmosphere EXplosive) standard, and defined as explosion-proof,
LED light sources are used, the main advantage of which lies above all in the long
duration which, in addition to being advantageous in economic terms, brings with it
the need for a lower number of maintenance interventions.
[0009] Consequently, the exposure of operators to the risk of explosions and/or fires is
significantly reduced, increasing the safety of use of the lighting apparatuses.
[0010] In known lighting apparatuses, in particular in those which use a LED light source,
there is the primary need to prevent any dangerous substance, in terms of flammability
or explosion, from coming into contact with the light source.
[0011] In some known lighting apparatuses, the light source is hermetically insulated from
the external atmosphere, for example, it is completely covered, and then sealed, by
means of a layer of transparent polymeric resin.
[0012] A first disadvantage of known explosion-proof lighting apparatuses whose components
in contact with the external atmosphere are made of metal material is that it is not
possible to install them in chemically aggressive environments against the metal material
itself.
[0013] Another disadvantage of known explosion-proof lighting apparatuses is that the presence
of the sealing polymeric resin, as described above, alters the light emission and
the color rendering index of the light source, causing an absorption of the light
radiation emitted.
[0014] Furthermore, the polymeric resin is subject to degradation due to aging and, since
it cannot be replaced, as time passes, it reduces the luminous efficiency of the apparatus.
[0015] There is therefore a need to perfect a lighting apparatus that can be used, at most,
in all environments with an intermediate risk of explosion (zone 1 according to ATEX
standards) which can overcome at least one of the disadvantages of the state of the
art.
[0016] A first purpose of the present invention is to provide an explosion-proof lighting
apparatus that is suitable to be installed even in environments that are chemically
aggressive toward metal materials exposed to the external environment.
[0017] Another purpose of the present invention is to not alter the light emission and the
color rendering index of the light source.
[0018] Another purpose is that the luminous efficiency of the apparatus is high and constant
throughout its entire usable life.
[0019] Another purpose is to perfect a method to produce a lighting apparatus that is simple,
repeatable in series, efficient, rapid and with low implementation costs, which allows
easier assembly operations, and which allows to obtain a long duration of the apparatus
itself.
[0020] Consequently, a final purpose of the present invention is to provide a lighting apparatus
which, even by increasing its performance in terms of luminous efficiency and duration
over time, has production costs that are no higher, or possibly lower, than those
of the apparatuses belonging to the state of the art.
[0021] The Applicant has devised, tested and embodied the present invention to overcome
the shortcomings of the state of the art and to obtain these and other purposes and
advantages.
SUMMARY OF THE INVENTION
[0022] The present invention is set forth and characterized in the independent claims. The
dependent claims describe other characteristics of the present invention or variants
to the main inventive idea.
[0023] In accordance with the above purposes, the present document discloses a lighting
apparatus, indicated hereafter as apparatus, which comprises a containing body, provided
with two open ends, a dissipator support, which divides the containing body into a
housing and a compartment, a light source attached to the dissipator support in correspondence
with the housing, and two closing elements, both configured to close the open ends
of the containing body.
[0024] The containing body is made in a single body and of polymeric material.
[0025] The housing and the compartment are hermetically sealed, with respect to the external
environment, by means of the closing elements which are attached in correspondence
with the open ends of the containing body.
[0026] According to some embodiments, the closing elements are made of polymeric material.
[0027] In this case, the housing and the compartment are hermetically sealed, with respect
to the external environment, by means of the interposition of sealing elements made
of a material with sealing properties between the open ends of the containing body
and the closing elements.
[0028] The containing body comprises a containing portion and a diffusion portion, the latter
being made of a transparent and/or translucent polymeric material.
[0029] According to some embodiments, the containing portion comprises inside it at least
two upper protuberances and at least two lower protuberances.
[0030] Each upper protuberance faces the corresponding lower protuberance, so as to create
a first cavity between them.
[0031] The first cavities are configured to accommodate and maintain in position the dissipator
support.
[0032] According to some embodiments, the dissipator support comprises at least two first
protuberances configured to be inserted inside the first cavities.
[0033] In accordance with other embodiments, a sheet of glass is positioned in the housing,
attached to the dissipator support, defining with the latter a chamber separated from
the external environment, in which the light source is disposed.
[0034] The chamber is hermetically sealed by means of the sealing elements and sealing material
applied along the entire periphery of the sheet of glass.
[0035] According to some embodiments, the dissipator support comprises two second protuberances
configured to support the sheet of glass and to delimit the chamber.
[0036] Each second protuberance delimits a second cavity configured to position and possibly
additionally prevent the displacement of the sealing material.
[0037] According to other embodiments, the dissipator support is configured to rest on the
at least two upper protuberances and comprises at least one end portion configured
to attach the dissipator support to the containing body by means of attachment means
of the closing elements.
[0038] In this way, a lighting apparatus is obtained that overcomes the limits of the state
of the art and eliminates the defects present therein.
[0039] In particular, a simple and versatile apparatus is obtained that can be used in all
environments that are chemically aggressive toward metal materials and that have at
most an intermediate risk of explosion (zone 1 according to ATEX regulations).
[0040] The present invention also concerns a method to produce a lighting apparatus which
comprises the following steps:
- producing, in a single body, a containing body provided with two open ends;
- producing a dissipator support;
- mounting a light source on the dissipator support;
- mounting the dissipator support inside the containing body, delimiting a housing containing
the light source and a compartment;
- sealing the open ends of the containing body by assembling closing elements together
with corresponding sealing elements, in order to obtain a hermetic closure of the
housing and the entire apparatus.
[0041] According to some embodiments, the method to produce the lighting apparatus can also
include the steps of:
- positioning a sheet of glass in contact with the dissipator support so as to delimit
a chamber containing the light source;
- sealing the chamber by applying, along the entire periphery of the sheet of glass,
sealing material and possible sealing elements.
[0042] In this way, a simple, repeatable and reliable method to produce a lighting apparatus
is obtained, in which the production steps and the corresponding assembly times are
optimized, minimizing the final production costs of the apparatus itself.
BRIEF DESCRIPTION OF THE DRAWINGS
[0043] These and other aspects, characteristics and advantages of the present invention
will become apparent from the following description of some embodiments, given as
a non-restrictive example with reference to the attached drawings wherein:
- fig. 1 is a perspective view of a lighting apparatus;
- fig. 2 is an exploded perspective view, in partial section, of the lighting apparatus
of fig. 1;
- fig. 3 is a cross-section view along plane III-III of fig. 1, according to an embodiment
of the present invention;
- fig. 3a shows detail A, indicated in fig. 3, enlarged;
- fig. 4 is a cross-section view along plane III-III of fig. 1, according to an alternative
embodiment of the present invention;
- fig. 4a shows detail B, indicated in fig. 4, enlarged.
[0044] To facilitate comprehension, the same reference numbers have been used, where possible,
to identify identical common elements in the drawings. It is understood that elements
and characteristics of one embodiment can conveniently be incorporated into other
embodiments without further clarifications.
DESCRIPTION OF SOME EMBODIMENTS
[0045] We will now refer in detail to the possible embodiments of the invention, of which
one or more examples are shown in the attached drawings, by way of a non-limiting
illustration. The phraseology and terminology used here is also for the purposes of
providing non-limiting examples.
[0046] The attached drawings are used to describe some embodiments of a lighting apparatus
10, hereafter referred to as apparatus, and of a corresponding production method.
[0047] The present apparatus 10 comprises a containing body 11 provided with two open ends,
a dissipator support 22, at least one light source 16 and two closing elements 17,
18.
[0048] The closing elements 17, 18 are configured to close the open ends of the containing
body 11.
[0049] The closing elements 17, 18 can be configured to be applied to the respective opposite
ends of the containing body 11 by means of suitable attachment means 19 such as, for
example, self-tapping screws.
[0050] In accordance with a preferential embodiment, the containing body 11, as well as
the closing elements 17, 18, can be made of polymeric material.
[0051] The polymeric material can be selected from polycarbonate, polyester resin, epoxy
resin, polyester resin reinforced with glass fibers, or suchlike, or combinations
thereof.
[0052] One advantage of using polymeric materials is that the apparatus 10 can be used in
all environments that are chemically aggressive toward metal materials. For example,
it can be used in environments where corrosive substances such as nitric acid or pentane,
or suchlike, are present.
[0053] According to the present invention, as shown in the attached drawings, the containing
body 11 is made in a single body.
[0054] Furthermore, the containing body 11 can have horizontal sections, according to a
horizontal plane Y, having at least two parallel opposite sides, for example in the
shape of a parallelogram, rectangular, square or trapezoidal. The containing body
11 also has a transverse section, according to a plane perpendicular to the horizontal
plane Y, closed and empty inside, for example, shaped almost as an O, rectangular
or square.
[0055] According to some embodiments, the containing body 11 is made by means of molding,
extrusion or coextrusion, preferably by means of coextrusion, while the closing elements
17, 18 are made by means of molding.
[0056] According to some embodiments, the containing body 11 comprises a containing portion
11a and a diffusion portion 11b which are made in a single body, each made of polymeric
material.
[0057] The diffusion portion 11b is disposed in the lower part of the containing body 11
facing the light source 16. The diffusion portion 11b is configured to suitably diffuse
the beam of light generated by the light source 16. For example, the diffusion portion
11b can eliminate the risk of glare and therefore considerably increase visual comfort.
[0058] According to one possible embodiment, the diffusion portion 11b is made of a transparent
and/or translucent polymeric material such as, for example, polycarbonate (figs. 3,
3a, 4 and 4a).
[0059] The containing portion 11a, on the other hand, can be made of an opaque polymeric
material such as a polyester or epoxy resin, or a transparent and/or translucent material,
such as polycarbonate.
[0060] According to some embodiments, the containing portion 11a and the diffusion portion
11b are each made of a transparent and/or translucent polymeric material, possibly
of the same transparent and/or translucent polymeric material.
[0061] According to some embodiments, the external surface of the containing portion 11a
and of the diffusion portion 11b can be smooth or rough to the touch, for example,
it can be provided with grooves parallel to a longitudinal axis X of the apparatus
10.
[0062] The light source 16 can be any device whatsoever capable of converting the electrical
power supplied by a power supply and control unit 14 into a beam of light such as,
for example, incandescent, halogen, discharge, LED lights or suchlike.
[0063] According to some embodiments, as shown in figs. 3, 3a, 4, 4a, the containing body
11 can be configured to accommodate the dissipator support 22 on which, in correspondence
with a rest surface 22a thereof facing the diffusion portion 11b, the light source
16 is attached.
[0064] According to some embodiments, the rest portion 22a is parallel to the horizontal
plane Y and extends along the longitudinal axis X of the apparatus 10.
[0065] The dissipator support 22 is configured to optimally disperse the heat generated
by the light source 16.
[0066] In this regard, the dissipator support 22 can be made of metal material, for example
steel, aluminum or copper, preferably of aluminum alloy. Metal materials, in fact,
have the advantage of having a good thermal conductivity, being able to dissipate
the heat produced, for example, by the light source 16. Furthermore, the aluminum
alloy is also a light and corrosion resistant material.
[0067] In accordance with possible embodiments, the dissipator support 22 can be made by
means of molding, die casting or extrusion, preferably by means of extrusion.
[0068] According to some embodiments, with reference to figs. 3, 3a, 4 and 4a, the containing
portion 11a of the containing body 11 can comprise inside it at least two upper protuberances
27a and at least two lower protuberances 27b. Each upper protuberance 27a faces the
corresponding lower protuberance 27b, in such a way as to create a first cavity 27
between them.
[0069] According to the present invention, the first cavity 27 has a development parallel
to the longitudinal axis X of the containing body 11.
[0070] According to some embodiments, the first cavity 27 is also configured to accommodate
and maintain in position the dissipator support 22.
[0071] In this regard, the dissipator support 22 comprises at least two first protuberances
23.
[0072] In accordance with a first variant, the first protuberances 23 are configured to
be inserted inside the respective first cavities 27.
[0073] In accordance with a second variant, the first protuberances 23 are configured to
rest on the at least two upper protuberances 27a.
[0074] In the latter case, the dissipator support 22 can comprise at least one end portion
32 configured to attach the dissipator support 22 to the containing body 11 by means
of attachment means 19 of the closing elements 17, 18.
[0075] The dissipator support 22, once mounted inside the containing body 11, divides the
latter into a housing 12 and a compartment 31 which are disposed, respectively, in
the upper part and in the lower part of the containing body 11.
[0076] The housing 12 can be configured to accommodate the light source 16 inside it.
[0077] According to a preferential embodiment, the dissipator support 22 is configured to
position a dissipator element 16a of the light source 16 in contact with the rest
surface 22a, capable of dissipating the heat produced by the light source 16.
[0078] According to some embodiments, in order to obtain a watertight insulation of the
light source 16, sealing elements 21 are applied between the open ends of the containing
body 11 and the closing elements 17, 18, the sealing elements 21 being made of a material
with sealing properties and being configured to insulate the light source 16 from
the external environment.
[0079] In this way, an apparatus 10 is obtained which can be used in all environments which
have a risk of explosion that is, at most, low (zone 2 according to ATEX regulations).
The apparatus 10 can also be used in environments with a lower risk than the low one,
for example in environments in which there is no risk of explosion.
[0080] According to some embodiments, the dissipator support 22 can be configured to position
a sheet of glass 24 in such a way that it is distanced from or, possibly, in contact
with, the light source 16.
[0081] According to some embodiments, in order to obtain a watertight insulation of the
light source 16, sealing material 25 and possible sealing elements 21 are applied
along the entire periphery of the sheet of glass 24.
[0082] In this way, the apparatus 10 can be used, at most, in environments with an intermediate
risk of explosion (zone 1 according to ATEX regulations).
[0083] The sealing material 25 can be a synthetic elastomer used to make packings (for example,
silicone).
[0084] According to some embodiments, the sheet of glass 24, positioned on the dissipator
support 22, delimits a chamber 26 separated from the external environment, comprising
the light source 16 inside it.
[0085] According to one possible embodiment, the dissipator support 22 is equipped with
two second protuberances 30 which extend outward and along its entire length. Each
second protuberance 30 comprises a lower surface 30a configured to support the sheet
of glass 24. These second protuberances 30 are also configured to obtain, during the
assembly step, the centering of the light source 16 by means of the possible dissipator
element 16a.
[0086] According to some embodiments, the lower surface 30a faces toward the external side.
[0087] The second protuberances 30 can also be configured to delimit the chamber 26.
[0088] Furthermore, at least each second protuberance 30 is disposed in such a way as to
delimit a second cavity 28, placed laterally with respect to the rest zone of the
light source 16. This second cavity 28 extends without a break in continuity between
the two open ends of the containing body 11.
[0089] According to some embodiments, the dissipator support 22 comprises at least two third
protuberances 33 disposed on the same side and outside the second protuberances 30,
in such a way as to delimit the second cavity 28.
[0090] The second cavity 28 is configured to position and possibly additionally prevent
the displacement of the sealing material 25.
[0091] According to a preferential embodiment, and with reference to figs. 3a and 4a, a
wall 28a of each second cavity 28 which cooperates with the sealing material 25 has
an inclination angle α, with respect to the vertical, facing toward the inside of
the second cavity 28.
[0092] This solution has the advantage of preventing the sealing material 25, which fills
each second cavity 28, from being displaced, for example, following impacts or due
to aging. In this way, the sheet of glass 24, once positioned, remains fixed in any
condition whatsoever.
[0093] According to a preferential embodiment, each third protuberance 33 can comprise at
least one holding mean 34 which protrudes outward, laterally with respect to the second
cavity 28.
[0094] The at least one holding mean 34 acts as a striker to correctly position and center
the sheet of glass 24 during the assembly steps, delimiting the chamber 26 in which
the light source 16 is disposed.
[0095] In particular, by also using a sheet of glass 24 with sealing material 25, an apparatus
10 is obtained which can be used, at most, even in environments with an intermediate
risk of explosion (zone 1 according to ATEX regulations).
[0096] Furthermore, the sheet of glass 24 is not subject to alteration of transparency characteristics
with aging, throughout the entire operating life of the apparatus 10.
[0097] In order to reduce the number of items stored in the warehouse, the dissipator support
22 can always comprise at least two second protuberances 30 and at least two third
protuberances 33 which delimit the two second cavities 28. In this way, two possible
variants of the apparatus 10 can be provided with the same dissipator support 22 (without
sheet of glass 24 and without sealing material 25; with sheet of glass 24 and with
sealing material 25).
[0098] According to one possible variant, the dissipator support does not comprise any second
30 and third 33 protuberance whatsoever.
[0099] According to preferred embodiments, the containing body 11 acts as a casing for the
other elements that make up the apparatus 10, and constitutes the bearing structure
of the latter.
[0100] The compartment 31 of the containing body 11 can be configured to accommodate at
least one support element 13.
[0101] The support element 13 is configured in such a way as to accommodate and attach on
it the power supply and control unit 14, which comprises electronic elements configured
to power and control the light source 16.
[0102] The at least one support element 13 can be made, in a single body, during the production
of the containing body 11 or of the dissipator support 22, for example by means of
extrusion.
[0103] This solution has the advantage of eliminating any mechanical work with stock removal
and reducing assembly times for the production of the apparatus 10.
[0104] According to some embodiments, the containing body 11 can comprise, facing inward,
first coupling elements 29.
[0105] Alternatively or in addition, the dissipator support 22 can comprise, on the opposite
side of the rest surface 22a, second coupling elements 35.
[0106] The first 29 and second 35 coupling elements are configured to mount the support
element 13 of the power supply and control unit 14, without the aid of additional
attachment elements.
[0107] According to one possible embodiment, shown in figs. 1 and 2, one of the closing
elements 17 comprises a hole 36 concentric, or not, with the longitudinal axis X,
while the other closing element 18 is blind.
[0108] The hole 36 is configured to accommodate a watertight cable gland element 20.
[0109] The cable gland element 20 is configured to allow the passage of the electrical cables
that connect to the power supply and control unit 14.
[0110] According to a preferential alternative embodiment, the closing elements 17, 18 are
the same and both comprise a hole 36.
[0111] In this case, the cable gland element 20 is mounted on one of the closing elements
17, while a watertight cap is mounted on the other closing element 18, making it blind.
[0112] According to another embodiment, the closing elements 17, 18 can be made of a material
with sealing properties, thus simultaneously achieving both the functions of the closing
elements 17, 18 and of the sealing elements 21.
[0113] In accordance with some embodiments, a method to produce a lighting apparatus 10
is provided, which comprises the steps of:
- producing, in a single body, a containing body 11 provided with two open ends;
- producing a dissipator support 22;
- mounting a light source 16 on the dissipator support 22;
- mounting the dissipator support 22 inside the containing body 11, delimiting a housing
12 containing the light source 16 and a compartment 31;
- sealing the open ends of the containing body 11 by assembling closing elements 17,
18 together with possible corresponding sealing elements 21, in order to obtain a
hermetic closure of the housing 12 and of the entire apparatus 10.
[0114] The mounting of the dissipator support 22 can occur without the aid of attachment
elements, such as screws, bolts and suchlike, by inserting it, for example sliding
or by applying pressure, in correspondence with two first cavities 27 made in the
containing body 11 which are parallel to the longitudinal axis X.
[0115] In accordance with possible embodiments, the method to produce the apparatus 10,
according to the present invention, can possibly also include the steps of:
- positioning a sheet of glass 24 in contact with the dissipator support 22 in such
a way as to delimit a chamber 26 containing the light source 16;
- sealing the chamber 26 by applying, along the entire periphery of the sheet of glass
24, sealing material 25 and possible sealing elements 21.
[0116] It is clear that modifications and/or additions of parts or steps may be made to
the lighting apparatus 10 and to the corresponding production method as described
heretofore, without departing from the field and scope of the present invention as
defined by the claims.
[0117] In the following claims, the sole purpose of the references in brackets is to facilitate
reading: they must not be considered as restrictive factors with regard to the field
of protection claimed in the specific claims.
1. Lighting apparatus (10) comprising a containing body (11) provided with two open ends
and a dissipator support (22) which divides said containing body (11) into a housing
(12) and a compartment (31) as well as two closing elements (17, 18) and at least
one light source (16), characterized in that said containing body (11) is made in a single body and of polymeric material and in that said housing (12) and compartment (31) are hermetically sealed by means of said closing
elements (17, 18) which are attached in correspondence with the open ends of said
containing body (11).
2. Apparatus (10) as in claim 1, characterized in that said closing elements (17, 18) are made of polymeric material and in that said housing (12) and said compartment (31) are hermetically sealed by means of the
interposition of sealing elements (21) between the open ends of said containing body
(11) and said closing elements (17, 18).
3. Apparatus (10) as in claims 1 or 2, characterized in that said containing body (11) comprises a containing portion (11a) and a diffusion portion
(11b) which is made of a transparent and/or translucent polymeric material.
4. Apparatus (10) as in claim 3, characterized in that said containing portion (11a) comprises inside it at least two upper protuberances
(27a) and at least two lower protuberances (27b), wherein each upper protuberance
(27a) is facing the corresponding lower protuberance (27b) so as to create between
them a first cavity (27) configured to accommodate and maintain in position said dissipator
support (22).
5. Apparatus (10) as in claim 4, characterized in that said dissipator support (22) comprises at least two first protuberances (23) configured
to be inserted inside said first cavities (27).
6. Apparatus (10) as in any claim hereinbefore, characterized in that said at least one light source (16) is attached to said dissipator support (22) in
correspondence with said housing (12) and in that a sheet of glass (24) is positioned in said housing (12), attached to said dissipator
support (22), delimiting with the latter a chamber (26) separated from the external
environment and hermetically sealed by means of said sealing elements (21) and sealing
material (25), in which said light source (16) is disposed.
7. Apparatus (10) as in claim 6, characterized in that said dissipator support (22) comprises two second protuberances (30) configured to
support said sheet of glass (24) and to delimit said chamber (26), wherein at least
each of said second protuberances (30) delimits a second cavity (28) configured to
position and prevent the displacement of said sealing material (25).
8. Apparatus (10) as in any claim from 4 to 7, characterized in that said dissipator support (22) is configured to rest on the at least two said upper
protuberances (27a) and comprises at least one end portion (32) configured to attach
said dissipator support (22) to said containing body (11) by means of attachment means
(19) of said closing elements (17, 18).
9. Method to produce a lighting apparatus (10),
characterized in that it comprises the steps of:
- producing in a single body a containing body (11) provided with two open ends;
- producing a dissipator support (22);
- mounting a light source (16) on said dissipator support (22);
- mounting said dissipator support (22) inside said containing body (11), delimiting
a housing (12) containing said light source (16) and a compartment (31);
- sealing the open ends of said containing body (11) by assembling closing elements
(17, 18) together with corresponding sealing elements (21), in order to obtain a hermetic
closure of said housing (12) and of the entire apparatus (10).
10. Method as in claim 9,
characterized in that it comprises the steps of:
- positioning a sheet of glass (24) in contact with said dissipator support (22) so
as to delimit a chamber (26) containing said light source (16);
- sealing said chamber (26) by applying, along the entire periphery of said sheet
of glass (24), sealing material (25) and possible sealing elements (21).