Title: Apparatus for blocking ambient air of electrodeless lighting system and waveguide thereof
Abstract: An apparatus for blocking ambient air of an electrodeless lighting system comprises: a waveguide including a shaft hole so that a bulb shaft can be penetrated therethrough; a bulb motor mounted on a rear side of the waveguide and connected to a bulb, which is located on a front side of the waveguide, using the bulb shaft for rotating the bulb; and a sealing unit installed between the bulb motor and the waveguide for blocking inflow of ambient air to a direction of the bulb, that is, a sealing structure can be ensured so that the ambient air is not flowed into the light emitting area where the mesh screen is located, and thereby impurities are not flowed into the light emitting area to ensure the clear light emitting conditions, the oxidization of mesh screen can be reduced, and the stability of the lighting apparatus is improved and maintenance cost can be reduced.
Patent Number: 6,933,675 Issued on 08/23/2005 to Seo
| Inventors:
|
Seo; Seong-Tae (Daegu, KR)
|
| Assignee:
|
LG Electronics Inc. (KR)
|
| Appl. No.:
|
119404 |
| Filed:
|
April 8, 2002 |
Foreign Application Priority Data
| Feb 22, 2002[KR] | 2002-9660 |
| Current U.S. Class: |
315/39; 315/248; 315/118; 315/267; 315/344; 313/24 |
| Intern'l Class: |
H01J 065/04; H01J 007//26 |
| Field of Search: |
315/39,118,248,267,395.1,344,246,112
313/24,35,231.31
403/24
|
References Cited [Referenced By]
U.S. Patent Documents
| 5688064 | Nov., 1997 | Shanks.
| |
| 5998934 | Dec., 1999 | Mimasu et al.
| |
| 6617793 | Sep., 2003 | Choi et al.
| |
| 6680576 | Jan., 2004 | Jeon.
| |
| 6734638 | May., 2004 | Kang et al.
| |
| 6784619 | Aug., 2004 | Choi.
| |
| Foreign Patent Documents |
| 1298198 | Jun., 2001 | CN.
| |
| 0 604 306 | Dec., 1993 | EP.
| |
| 2000/-353495 | Dec., 2000 | JP.
| |
| 2001/-155505 | Jun., 2001 | JP.
| |
| WO 0070651 | Nov., 2000 | WO.
| |
Other References
Office Action issued by Chinese Patent Office in connection with corresponding
application No. 02119375.5 dated Dec. 31, 2004.
English translation of text of Chinese Office Action dated Dec. 31, 2004.
|
Primary Examiner: Wong; Don
Assistant Examiner: Tran; Chuc
Attorney, Agent or Firm: Ostrolenk, Faber, Gerb & Soffen, LLP
Claims
1. An apparatus for blocking ambient air of an electrodeless lighting system, comprising:
a waveguide including a shaft hole so that a bulb shaft can penetrate therethrough;
a bulb motor mounted on a rear side of the waveguide and connected to a bulb
by the bulb shaft, said bulb located on a front side of the waveguide; and
a hole forming pipe extending from a front side of the waveguide toward the bulb
motor, for forming the shaft hole; and
a hole gasket installed between the hole forming pipe and the bulb motor,
wherein the hole forming pipe includes a gasket recess so that the hole gasket
can be mounted thereon.
2. The apparatus of claim 1, wherein the bulb motor includes a boss portion where
the bulb shaft protrudes; and
the hole gasket is mounted between the hole forming pipe and the boss portion
of the bulb motor.
3. The apparatus of claim 1, wherein the hole gasket is formed in an o-ring shape.
4. The apparatus of claim 1, wherein the waveguide comprises:
a supporting rib formed between the hole forming pipe and a main body for supporting
the hole forming pipe.
5. The apparatus of claim 4, wherein the supporting rib is formed as a "+" structure
centered around the hole forming pipe.
6. An apparatus for blocking ambient air of an electrodeless lighting system, comprising:
a case;
a waveguide including a shaft hole through which a bulb shaft penetrates;
a mesh screen installed on an outlet portion of the waveguide, for blocking microwave
energy and passing light;
a bulb located in the mesh screen, for emitting light by the microwave energy;
a bulb motor mounted on a rear side of the waveguide and connected to the bulb
by the bulb shaft;
a sealing member installed between the bulb motor and the waveguide; and
a gasket installed between the case and the waveguide in order to prevent ambient
air from flowing into an area where the mesh screen is located.
7. The apparatus of claim 6, wherein the sealing member comprises:
a hole forming pipe extending from a front side of the waveguide toward the bulb
motor; and
a hole gasket installed between the hole forming pipe and the bulb motor.
8. The apparatus of claim 6, wherein the waveguide is fixed in the case by a
fixing bracket, and a plurality of gaskets are installed between the waveguide
and the fixing bracket and between the case and the fixing bracket.
9. The apparatus of claim 6, wherein the fixing bracket has a plurality of gasket
recesses in which a plurality of gaskets are inserted.
10. The apparatus of claim 6, further comprising:
a reflector installed on a front side of the case, for reflecting the light generated
in the bulb;
a cover glass installed on a front side of the reflector; and
a glass gasket installed between the reflector and the cover glass in order to
prevent ambient air from flowing into the area where the mesh screen is located.
11. The apparatus of claim 10, further comprising:
a reflector gasket installed between the case and the reflector in order to prevent
ambient air from flowing into the area where the mesh screen is located.
12. The apparatus of claim 6, further comprising:
a globe of spherical shape installed on a front side of the case, for permeating
the light generated in the bulb; and
a globe gasket installed between the case and the globe, for preventing ambient
air from flowing into the area where the mesh screen is located.
13. An apparatus for blocking ambient air of an electrodeless lighting system, comprising:
a case;
a waveguide including a shaft hole through which a bulb shaft penetrates;
a mesh screen installed on an outlet portion of the waveguide, for blocking microwave
energy and passing light;
a bulb located in the mesh screen, for emitting light by the microwave energy;
a bulb motor mounted on a rear side of the waveguide and connected to the bulb
by the bulb shaft;
a reflector installed on a front side of the case, for reflecting the light generated
in the bulb;
a cover glass installed on a front side of the reflector;
a sealing member installed between the bulb motor and the waveguide; and
a reflector gasket installed between the case and the reflector in order to prevent
ambient air from flowing into an area where the mesh screen is located.
14. The apparatus of claim 13, further comprising:
a plurality of gaskets respectively installed between the waveguide and a fixing
bracket for fixing the waveguide to the case and between the case and the fixing
bracket.
15. The apparatus of claim 14, wherein the fixing bracket has a plurality of
gasket recesses in which a plurality of gaskets are inserted.
16. The apparatus of claim 14, further comprising:
a glass gasket installed between the reflector and the cover glass in order to
prevent ambient air from flowing into the area where the mesh screen is located.
17. An apparatus for blocking ambient air of an electrodeless lighting system, comprising:
a case;
a waveguide including a shaft hole through which a bulb shaft is penetrated;
a mesh screen installed on an outlet portion of the waveguide, for blocking microwave
energy and passing light;
a bulb located in the mesh screen, for emitting light by the microwave energy;
a bulb motor mounted on a rear side of the waveguide and connected to the bulb
by the bulb shaft;
a globe of spherical shape installed on a front side of the case, for permeating
the light generated in the bulb;
a sealing member installed between the bulb motor and the waveguide; and
a globe gasket installed between the case and the globe, for preventing ambient
air from flowing into an area where the mesh screen is located.
18. The apparatus of claim 17, wherein the globe has a cylindrical fixed portion
extended at an opened part communicated to the outlet portion of the waveguide,
said fixed portion extended at an opened part communicated to the outlet portion
of the waveguide, said fixed portion formed with screw threads on a circumferential
surface thereof; and
a fixing ring having screw threads on a circumferential surface thereof is installed
on the case so that the fixed portion of the globe is coupled thereto.
19. The apparatus of claim 18, wherein the globe gasket is inserted between the
fixed portion of the globe and a front surface of the case.
20. The apparatus of claim 19, wherein a gasket recess is formed in the fixed
portion of the globe or on the front surface of the case, so that the globe gasket
is inserted therein.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an electrodeless lighting system using microwave,
and particularly, to an apparatus for blocking ambient air of an electrodeless
lighting system for preventing ambient air from flowing into an area where a bulb
and a mesh screen are installed.
2. Description of the Background Art
Generally, an electrodeless lighting system is an apparatus for emitting
visible rays or ultraviolet rays by radiating microwave to an electrodeless plasma
bulb, and it has longer life span that that of incandescent lamp or fluorescent
lamp and has superior lighting effect.
FIG. 1 is a longitudinal cross-sectional view showing an electrodeless lighting
system according to the conventional art.
The conventional electrodeless lighting system comprises: a magnetron
2
installed in a case
1 for generating microwave; a high voltage generator
3 for providing the magnetron
2 with high voltage after raising the
utility AC power source to the high voltage; a waveguide
4 for transmitting
the microwave generated in the magnetron
2; a mesh screen
6 installed
on an outlet portion of the waveguide for blocking a leakage of the microwave and
for passing light; and a bulb
5, in which filled material becomes plasma
by the microwave transmitted through the waveguide
4 to emit the light,
located in the mesh screen
6.
In the electrodeless lighting system like above, a reflector
7 for reflecting
forward the light generated in the bulb
5 is disposed around the mesh screen
6 in front of the case
1, and a mirror
8 for passing the microwave
transmitted through the waveguide
4 and reflecting the light radiated from
the bulb
5 is installed in an outlet portion
4a of the waveguide
4.
On the other hand, a fan housing
9a, a cooling fan
9b,
and a fan motor
9c are installed on rear side of the case
1
for cooling down the magnetron
2 and the high voltage generator
3
as air cooling method.
In addition, a bulb motor
5b is installed on bottom surface of
the
waveguide
4 so as to rotate and cool down the bulb
5, and a bulb
shaft
5a which is connected as penetrating the waveguide
4
is installed between the bulb motor
5b and the bulb
5.
And holes
4b and
8a are formed on the waveguide
4
and on the mirror
8 so as to pass the bulb shaft
5a.
In the electrodeless lighting system constructed above, when an electric source
is applied to the high voltage generator
3, the high voltage generator
3
raises the utility AC power to high voltage and provides the magnetron
2
with the high voltage. And the magnetron
2 generates the microwave having
ultra high frequency.
The generated microwave is radiated into the mesh screen
6 through the
waveguide
4, and discharges the material filled in the bulb
5 to
emit the light having its own emission spectrum. In addition, the light generated
in the bulb
5 is reflected on the mirror
8 and the reflector
7
toward front side to illuminate a lighting area.
On the other hand, when the electrodeless lighting system is operated, the magnetron
2 and the high voltage generator
3 generate heat of high temperature.
Therefore, the fan motor
9c and the cooling fan
9b are
operated to cool down inside of the case
1 as the air cooling method.
That is, when the cooling fan
9b is operated, the air which is
flowed into the case
1 through the fan housing
9a cools down
the magnetron
2 and the high voltage generator
3 and then goes out
through a discharge hole
1a.
However, the ambient air flowed into the case
1 as the cooling fan
9b is operated is also flowed in the light emitting area in which
the bulb
5 and the mesh screen
6 are located through the hole
4b
formed on a center part of the waveguide
4 and the hole
8a
of the mirror
8.
In addition, impurities such as dust are also flowed with the ambient air when
the air is flowed into the light emitting area where the bulb
5 and the
mesh screen
6 are located, and the flowed ambient air and the impurities
oxidizes the mesh screen
6 which is made using a metal. And therefore, the
life span of the mesh screen
6 is reduced.
That is, the light emitting area in which the mesh screen
6 is located
is considerably high temperature environment because the bulb
5 generates
high temperature over 1000° C., and at that time, the ambient air and the
impurities flowed into the light emitting area contact to the mesh screen
6
of metal, and therefore, the oxidation rate is greatly increased.
Therefore, if the mesh screen is oxidized and burned, the microwave may
leak. Therefore, the stability of the lighting apparatus is decreased, and the
maintenance cost of the lighting apparatus is very high because the mesh screen
6 needs to be replaced frequently.
SUMMARY OF THE INVENTION
Therefore, an object of the present invention is to provide an apparatus
for blocking ambient air of an electrodeless lighting system which is able to prevent
ambient air from being flowed into a light emitting area and to prevent the mesh
screen from being damaged by sealing the light emitting area where the mesh screen
is located so that the ambient air can not be flowed into the light emitting area.
Also, another object of the present invention is to provide an apparatus for
blocking ambient air of an electrodeless lighting system which is able to increase
stability of the lighting apparatus and reduce maintenance cost of the lighting
apparatus by preventing the mesh screen from being oxidized and damaged.
To achieve these and other advantages and in accordance with the purpose of the
present invention, as embodied and broadly described herein, there is provided
an apparatus for blocking ambient air of an electrodeless lighting system comprising:
a waveguide having a shaft hole so that a bulb shaft can be passed therethrough;
a bulb motor mounted on rear side of the waveguide and connected to a bulb, which
is located on front side of the waveguide, with the bulb shaft for rotating the
bulb; and a sealing means installed between the bulb motor and the waveguide so
as to block the ambient air toward the direction of the bulb.
According to an embodiment of the present invention, there is provided
an electrodeless lighting system comprising: a case; a waveguide located in the
case so as to be protruded toward outer side for transmitting microwave from a
magnetron; a mesh screen installed on an outlet portion of the waveguide for blocking
the microwave and passing light; a bulb located in the mesh screen for generating
the light by the microwave; a bulb motor mounted on rear side of the waveguide
and connected to the bulb using a bulb shaft inserted into the shaft hole for generating
the bulb; and a sealing means installed between the bulb motor and the waveguide
for blocking the ambient air toward the direction of the bulb.
The sealing means comprises a hole forming pipe extended from the front side
of the waveguide toward the bulb motor direction for forming the shaft hole, and
a first gasket member installed between the hole forming pipe and the bulb motor.
The hole forming pipe includes a gasket recess so that the gasket member can
be mounted, and the gasket member is formed as an o-ring.
A second gasket member is installed between the case and the waveguide so as
to
prevent the ambient air from flowing into the area where the mesh screen is located.
The waveguide is fixed inside the case using a fixing bracket, and a plurality
of the second gasket members are installed between the waveguide and the fixing
bracket, and between the fixing bracket and the case, respectively.
The electrodeless lighting system further comprises a reflector installed on
front side of the case for reflecting the light generated in the bulb toward the
front direction, and a cover glass installed on front side of the reflector.
A third gasket member is installed between the case and the reflector so that
the
ambient air is not flowed into the area in which the mesh screen is located.
According to another embodiment of the present invention, there is provided
an electrodeless lighting system comprising: a case; a waveguide having a shaft
hole in front-rear direction located in the case so as to be protruded toward the
outer side for transmitting microwave from a microwave generator; a mesh screen
installed on an outlet portion of the waveguide for blocking the microwave and
passing the light; a bulb located in the mesh screen for emitting the light by
the microwave; a bulb motor mounted on rear side of the waveguide and connected
to the bulb using a bulb shaft inserted in the shaft hole for rotating the bulb;
a sealing means installed between the bulb motor and the waveguide for blocking
the inflow of ambient air toward the direction of the bulb; and a globe of spherical
shape installed on front side of the case so that the light generated in the bulb
can be permeated to all directions.
A fourth gasket member is installed between the case and the reflector for blocking
the inflow of the ambient air toward the area where the mesh screen is located.
The foregoing and other objects, features, aspects and advantages of the present
invention will become more apparent from the following detailed description of
the present invention when taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are included to provide a further understanding
of the invention and are incorporated in and constitute a part of this specification,
illustrate embodiments of the invention and together with the description serve
to explain the principles of the invention.
In the drawings:
FIG. 1 is a longitudinal cross-sectional view showing an electrodeless lighting
system according to the conventional art;
FIG. 2 is a longitudinal cross-sectional view showing an electrodeless lighting
system according to a first embodiment of the present invention;
FIG. 3 is a detailed view showing "A" part in FIG. 2;
FIG. 4 is a detailed view showing disintegrated state of "B" part in FIG. 2;
FIG. 5 is a bottom view showing a waveguide shown in FIG. 2;
FIG. 6 is a longitudinal cross-sectional view showing an electrodeless lighting
system according to a second embodiment of the present invention; and
FIG. 7 is a detailed view showing "C" part in FIG. 6.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Reference will now be made in detail to the preferred embodiments of the
present invention, examples of which are illustrated in the accompanying drawings.
FIG. 2 is a longitudinal view showing an electrodeless lighting system according
to a first embodiment of the present invention, FIG. 3 is a detailed view showing
"A" part of FIG. 2, FIG. 4 is a detailed view showing a disintegrated state of
"B" part of FIG. 2, and FIG. 5 is a bottom view showing a waveguide shown in FIG.
2.
As shown in FIG. 2, a magnetron
20 for generating microwave and a high
voltage generator
30 for raising utility AC power to high voltage and providing
the high voltage are disposed in a case
10.
A waveguide
40 for transmitting microwave generated in the magnetron
20
is located between the magnetron
20 and the high voltage generator
30.
Herein, the waveguide
40 is fixed in the case
10 via a fixing
bracket
45 in the state of being fixed on the fixing bracket
45,
and an outlet portion
41 through which the microwave is discharged is located
as protruded toward the front side of the case
10.
A mesh screen
60 for blocking a leakage of the microwave and passing the
light is connected to the outlet portion of the waveguide
40, and a bulb
50, in which the filled material becomes plasma by the microwave energy
transmitted through the waveguide
40 to emit the light, is installed in
the mesh screen
60.
Herein, a mirror
65 for passing the microwave transmitted through
the waveguide
40 and reflecting the light radiated from the bulb
50
toward the front direction is installed inside the outlet portion
41 of
the waveguide.
A reflector
70 for reflecting the light generated in the bulb
50
toward the front direction intensively is installed on the front side of the case
10, and a cover glass
75 is disposed on front side of the reflector
75 so as to seal the inside and at the same time, to permeate the light
toward the front direction.
A fan housing
81, a cooling fan
83, and a fan motor
85 are
installed on rear side of the case
10 so as to cool down the magnetron
20
and the high voltage generator
30 using air cooling method, and a discharge
hole
15 is formed on a front surface of the case
10 so as to discharge
the air which was flowed in the case
10.
A bulb motor
53 is installed on a bottom surface of the waveguide
40
so as to cool down the bulb
50 as rotating the bulb, and the bulb motor
53 and the bulb
50 are mutually connected through a bulb shaft
55
which passes through a center part of the waveguide
40.
A shaft hole
42 is formed on the waveguide
40 so that the bulb
shaft
55 cam be passed therethrough.
The above electrodeless lighting system is constructed so that the ambient air
is flowed into the case
10 to cool down the magnetron
20, etc. Therefore,
gasket members for blocking the inflow path of the ambient air are installed so
that the light emitting area where the mesh screen
60 and the bulb
50
are located can be sealed completely from the outer side.
That is, the ambient air may be flowed into the area where the mesh screen
60
is located through a gap between the cover glass
75 and the reflector
70,
a gap between the reflector
70 and the case
10, a gap between the
case
10 and the bracket
45, a gap between the bracket
45 and
the waveguide
40, and the shaft hole
42 through which the bulb shaft
55 is penetrated.
Therefore, a glass gasket
91 seals the part where the cover glass
75 and the reflector
70 is coupled.
In addition, as shown in FIG. 3, a reflector gasket
92, a first bracket
gasket
93, and a second bracket gasket
94 are inserted into between
the reflector
70 and front surface of the case
10, between an inner
side surface of the case
10 and the fixing bracket
45, and between
the fixing bracket
45 and the waveguide
40 respectively, and the
inflow paths of the ambient air are blocked.
Herein, it is desirable that gasket recesses
70a,
45a,
and
45b are formed on the reflector
70 and the bracket
45
so that the gaskets
92,
93, and
94 are inserted. Surely, the
gasket recesses may be formed on the case
10 or the waveguide
40.
In addition, as shown in FIGS. 4 and 5, a hole forming pipe
43, which
is
extended from the front side of the waveguide
40 toward the direction of
the bulb motor
53 for forming the shaft hole
42, is formed in order
to seal the shaft hole
42 part of the waveguide
40 through which
the bulb shaft
55 is penetrated.
A hole gasket
95 of o-ring shape is inserted between the hole forming
pipe
43 and the bulb motor
53.
The hole forming pipe
43 includes a gasket recess
43a so
that the hole gasket
95 can be mounted, and a supporting rib
44 of
"+" structure is connected between the hole forming pipe and the main body of the
waveguide
40 so as to support the hole forming pipe
43.
In addition, the bulb motor
53 includes a boss portion
53a,
which is protruded than other parts of the motor, on a part where the shaft is
protruded, and the hole gasket
95 is mounted between the boss portion
53a
and the hole forming pipe
43.
On the other hand, the bulb motor
53 is mounted to a plurality of bosses
45 protruded on a bottom surface of the waveguide
40 as assembled
using a screw
46.
Operation of the apparatus for blocking ambient air of the electrodeless
lighting system according to the first embodiment of the present invention will
be described as follows.
When the electrodeless lighting system is operated, the fan motor
85
and the cooling fan
83 are operated to make ambient air flow into the case
10, as shown in FIG.
2. The flowed air cools down the magnetron
20,
and the high voltage generator
30, and then, goes out through the discharge
hole
15 on the case
10.
Herein, the hole gasket
95, the first and second bracket gaskets
93
and
94 are installed on the shaft hole
42 part of the waveguide
40,
between the waveguide
40 and the bracket
45, and between the bracket
45 and the case
10 respectively, and therefore, the ambient air can
not be flowed into the light emitting area where the bulb
50 and the mesh
screen
60 are located.
Also, the reflector gasket
92 and the glass gasket
91 are installed
between the case
10 and the reflector
71, and between the reflector
70 and the cover glass
75, and therefore, the ambient air is not
flowed in the reflector
70.
Therefore, the light emitting area, in which the mesh screen
60
and the bulb
50, surrounded by the cover glass
75, the reflector
70, the case
10, and the waveguide
40 is sealed completely
from the outer side, and thereby the oxidization of the mesh screen
60 by
being contacted to the outer air can be minimized and the damage of the mesh screen
60 can be prevented.
Also, the path to the inside of the light emitting area in the reflector
70
is completely blocked, and therefore, impurities such as dust which can be flowed
with the outer air are not flowed into the light emitting area, and a clean emitting
environment can be made.
FIG. 6 is a longitudinal cross-sectional view showing an electrodeless lighting
system according to the second embodiment of the present invention, and FIG. 7
is a detailed view showing "C" part in FIG.
6. Herein, same reference numerals
are used for same parts as those of the first embodiment, and descriptions for
those are omitted.
In the electrodeless lighting system according to the first embodiment of the
present invention, the reflector is used for reflecting the light toward the front
direction. However, in the electrodeless lighting system according to the second
embodiment of the present invention, a globe
100 of spherical shape is installed
so that the light generated in the bulb
50 can be reflected to all directions.
Herein, it is desirable that the globe
100 is made using an irregularly
reflecting material in order to minimize glaring phenomenon that a user may feel,
and only one surface is opened and fixed on the front surface of the case
10.
Referring to FIG. 7, the globe
100 includes a fixed portion
101
extended as a cylinder on the opened part, and a positive screw
102 is formed
on an outer circumferential surface of the fixed portion
101. In addition,
a fixing ring
110 in which a negative screw
112 is formed on an inner
circumferential surface is installed on the case
10.
Therefore, the globe
100 is fixed on the fixing ring
110
as screw assembling method and installed on front side of the case
10.
At that time, a globe gasket
120 is inserted between the fixed portion
110 of the globe
100 and the front surface of the case
10
in order to block the inflow of the ambient air. In addition, it is desirable that
a gasket recess
102 is formed on the globe
100 or on the case
100
so that the globe gasket
120 can be inserted therein.
On the other hand, sealing structures of the gap between the case
10 and
the bracket
45, the gap between the bracket
45 and the waveguide
40, and the shaft hole
42 part of the waveguide
40 are same
as those of the first embodiment.
In the electrodeless lighting system according to the second embodiment of the
present invention, the light emitting area inside the globe
100 is blocked
completely from the outer side. Therefore, the oxidization of the mesh screen
60
can be minimized, and the inflow of impurities such as the dust is prevented, thereby
clean lighting emitting environment can be made.
According to the apparatus for blocking ambient air of the electrodeless
lighting system of the present invention, a sealing structure can be ensured so
that the ambient air is not flowed into the light emitting area where the mesh
screen is located, and therefore, the impurities are not flowed into the light
emitting area. Therefore, clear light emitting conditions can be ensured, and the
phenomenon that the mesh screen is oxidized by the ambient air can be reduced.
Also, according to the present invention, the oxidization and damage of the
mesh screen are prevented, and therefore, the stability of the lighting apparatus
can be improved and the maintenance cost can be reduced.
As the present invention may be embodied in several forms without departing from
the spirit or essential characteristics thereof, it should also be understood that
the above-described embodiments are not limited by any of the details of the foregoing
description, unless otherwise specified, but rather should be construed broadly
within its spirit and scope as defined in the appended claims, and therefore all
changes and modifications that fall within the metes and bounds of the claims,
or equivalence of such metes and bounds are therefore intended to be embraced by
the appended claims.
*
