[0001] The present invention relates to a sectionable lamp holder supporting structure for
floodlights.
[0002] In particular, the present invention relates to a lamp holder supporting structure
for floodlights for the lighting of open environments, in dust-proof and humidity-proof
execution and utilizable for any type of lamp.
[0003] As it is known, floodlights for the lighting of open environments are subjected to
particularly severe environmental conditions and, therefore, the lamp holder supporting
structure has to guarantee tightness to dusts and humidity as well as the physical
resistance even under the most disadvantageous conditions.
[0004] The most usual cases of use for the floodlights in open environments are:
- lighting of areas intended for sport activities, where floodlights are subjected
to atmospherical agents, namely to rain, snow, frost,and they undergo the thermal
shock from summer-season to winter-season;
- lighting of road tunnels where the floodlights are subjected to the action of environmental
humidity, to dripping water as well as to the action of the corrosive agents produced
by the exhaust gas of motor vehicles in combination with the environmental humidity;
- lighting of industrial factories, where the floodlights, besides being exposed to
the action of the atmospherical agents as described hereinbefore, are subjected to
the action of corrosive substances discharged to the atmosphere by the plants of said
factories;
- lighting of streets and monuments, where the floodlights, arranged also in proximity
of the ground, besides being exposed to the atmospherical agents, are also subjected
to water and mud sprays and to the action of mechanical impacts.
[0005] A lamp holder supporting structure, by consequence, must withstand the physical-chemical
stresses above mentioned and prevent the penetration of dust moisture, corrosive vapours
and gases into the apparatus, which would irreparably lead to an (even considerable)
efficiency loss of the optical apparatus along with a decrease in amount and intensity
of the light emitted by the floodlight.
[0006] In addition to the foregoing, a lamp holder supporting structure must also withstand
the inner heat generated by the lamp and keep in spite of the action of the external
agents and of the inner heating, the electric insulation characteristics and a sufficient
mechanical resistance.
[0007] The lamp holder supporting structure has also to permit an easy removal (without
the use-of tools) of the lamp holder/ lamp group even after a few-year operation,
in order to keep low the ordinary maintenance costs.
[0008] The Applicant has now found that all the above-mentioned requirements and functions
are fully met by a dust-proof and humidity-proof lamp holder supporting structure
for floodlights, which consists of a drilled support, of a lamp holder, of an optical
chamber case and of means for fastening said components to one another, characterized
in that :
a) the supporting element is equipped, on the side turned to the optic chamber case,
with a peripherical groove for receiving a toroidal sealing gasket;
b) the fastening means comprise a U-shaped square fixed to the lamp holder and a support
for the square fixed to said supporting element and equipped with perimetrical teeth
and with guides, perpendicular to its plane, in which the two flanges of the square
are located and fixed, and
c) the optic chamber case exhibits a shaped hole with restraints suited to engage
in the teeth of the lamp holder support.
[0009] The drilled supporting element is provided, in its upper part, with ribs to facilitate
the manual gripping.
[0010] The lamp holdcr supporting structure forming the object of the present invention
is simple, rugged, reliable, it utilizes a hollow seal gasket, permits to adjust the
lamp position and can be installed on any floodlight and with any type of lamp.
[0011] Furthermore, it is easy to produce and requires a very low maintenance; it can be
manufactured from easily available and moderately expensive materials and guarantees
a Class II isolation according to CEI standards.
[0012] For a better understanding of the lamp holder supporting structure of the present
invention, a detailed description is given hereinafter making reference to the figures
of the attached drawing, in which :
- fig. 1 is a partially sectional view in side elevation of the lamp holder supporting
structure of the present invention, before being connected with the optic chamber
case;
- fig. 2 is a partially sectional view in side elevation of the lamp holder supporting
structure of figure 1, after the connection with the optic chamber case and showing
the tight seal generated by the special pneumatic gasket housed in the "lamp supporting
body" with the optic chamber case;
- fig. 3 is an exploded perspective view of the lamp holder supporting structure with
lamp holder and connections according to the invention. With reference to the figures,
the lamp holder supporting structure according to the invention includes a lamp holder
U-shaped square element (5) suited to support a lamp holder (8), and to which there
are electrically connected the two wires (9) which provide the electric connection
between the lamp holder (8) and the terminal (7) to which a cable (10), that electrically
feeds a lamp (11) is electrically connected.
[0013] The lamp holder square element (S) is supported, guided and positioned by a support
(2).
[0014] Said support is equipped with two vertical guides (12), in which square element (5)
slides.
[0015] Fastening means (13) permit a positioning of lamp holder square element (S) at different
levels depending on the size of the lamp (11), in order to center the lamp on the
optical axis of the reflector contained in the optical chamber (1).
[0016] The support (2) besides supporting and positioning the lamp holder square element
(5), is equipped with three teeth (14), which engage in corresponding teeth of the
optical chamber case (1), thus fixing and retaining on said case the whole lamp holder
supporting structure complex by exerting a pressure to cause gasket (4) to properly
adhere to the outer surface of the optical chamber case (1).
[0017] Supporting element (3) is fixed to the lamp holder square support (2) by means of
three self-tapping screws (15), which engage in three holes impressed on support (2)
by a mold.
[0018] Supporting element (3) exhibits a circumferential groove suited to receive the tight
gasket (4) and in the upper portion it exhibits a hole suited to house an element
acting as a packing gland and cable fastener (6), which is fixed by a lock nut.
[0019] Supporting element (3) exhibits three ribs of force, which are utilized by the operator
for operating the lamp holder supporting structure complex.
[0020] The operation of the lamp holder supporting structure complex can be clearly understood
from the preceding description; making reference to figures 1, 2 and 3 it is apparent
that said complex, resulting from the combination of parts 2, 3, 6, 5, 4, is engaged
by the teeth of part (2) to case (1) and locked to it by a proper rotation.
[0021] Through this last operation, gasket (4) is suitably pressed against the surface of
case (1), thereby providing the desired tightness to the penetration of dust and moisture.
1. A dust-proof and humidity-proof lamp holder supporting structure for floodlights,
consisting of a drilled supporting element, by a lamp holder, by an optic chamber
case and means for fastening said components to one another, characterized in that
:
a) the supporting element is equipped,on the edge turned to the optic chamber case,
with a circumferential groove for receiving a toroidal sealing gasket;
b) the fastening means comprise an U-shaped square element fixed to the lamp holder
and a square element support fixed to said supporting element and equipped with perimetrical
teeth and with guides, perpendicular to its plane, in which the two flanges of the
square element are positioned and fixed, and
c) the optic chamber case is provided with a shaped hole with teeth suited to engage
in the corresponding teeth of the square element support.
2. The lamp holder supporting structure according to claim 1, in which the drilled
supporting element exhibits, in its upper part, a hole suited to receive a packing
gland/cable fastener element.
3. The lamp holder supporting structure according to claim 1 or 2, characterized in
that the drilled supporting element exhibits, in its upper portion, ribs to facilitate
the manual gripping.
4. The lamp holder supporting structure according to any of the preceding claims,
in which the sealing gasket is hollow.