U.S. patent number 3,853,512 [Application Number 05/365,851] was granted by the patent office on 1974-12-10 for air purifier.
This patent grant is currently assigned to Nissan Motor Company, Limited. Invention is credited to Kazuo Hayashi.
United States Patent |
3,853,512 |
Hayashi |
December 10, 1974 |
AIR PURIFIER
Abstract
To enhance the dust collecting efficiency and to make it
possible to collect dust of relatively large particle sizes in a
compact construction, an air purifier comprises dust collecting
wall means including a dust collecting electrode and extending
helically to provide a continuous helical passageway for air to be
circulated in the air purifier and at least one charging electrode
also helically extending in the passageway for establishing an
electric field in the passageway through application of a
high-tension current to be collecting electrode or to the charging
electrode. Dust particles are collected by the dust collecting wall
means by reason of the centrifugal forces imparted to the particles
and the electrostatic attraction exercised on the particles as the
air is passed through the passageway. Also proposed is an improved
automotive air conditioning and cleaning system in which either
atmospheric air or a mixture of the atmospheric air and air
recirculated from a passenger compartment is cleaned before it is
directed into the passenger compartment.
Inventors: |
Hayashi; Kazuo (Yokohama,
JA) |
Assignee: |
Nissan Motor Company, Limited
(Yokohama, JA)
|
Family
ID: |
27317452 |
Appl.
No.: |
05/365,851 |
Filed: |
June 1, 1973 |
Foreign Application Priority Data
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|
|
|
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Nov 29, 1972 [JA] |
|
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47-137325 |
Nov 29, 1972 [JA] |
|
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47-137328 |
Nov 29, 1972 [JA] |
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47-137326 |
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Current U.S.
Class: |
96/59; 55/337;
55/351; 55/399; 55/458; 128/205.29; 361/231; 55/429; 55/459.3;
361/230; 454/158 |
Current CPC
Class: |
B03C
3/15 (20130101); B03C 3/14 (20130101) |
Current International
Class: |
B03C
3/14 (20060101); B03C 3/15 (20060101); B03C
3/04 (20060101); B03c 003/12 (); B03c 003/14 () |
Field of
Search: |
;55/127,124,126,136,137,138,139,154,155,150,151,130,134,146,148,149,337,351,339
;261/DIG.34 ;98/1,2,2.05,2.06,2.07,2.08,2.11,27,37,4R ;128/172,190
;317/4,262R,262AE |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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714,821 |
|
Sep 1931 |
|
FR |
|
730,960 |
|
May 1932 |
|
FR |
|
1,029,116 |
|
Mar 1953 |
|
FR |
|
931,625 |
|
Jul 1963 |
|
GB |
|
Primary Examiner: Talbert, Jr.; Dennis E.
Claims
What is claimed is:
1. An air purifier comprising a generally cylindrical casing having
an air inlet opening and an air outlet opening located
substantially centrally of the casing, dust collecting wall means
positioned within said casing and providing a continuous passageway
extending spirally between the air inlet and outlet openings in
said casing, said wall means including at least one dust collecting
electrode for connection to a first electric terminal, and at least
one charging electrode extending spirally in and along said
passageway and electrically isolated from said collecting
electrode, said charging electrode being for connection to a second
electric terminal having a polarity opposite to the polarity of the
first electric terminal for thereby establishing an electric field
between the charging and collecting electrodes so that particles of
dust entrained in air directed into said passageway through said
air inlet opening become ionized and are attracted to said dust
collecting wall means as the air is circulated through said
passageway from said air inlet opening to said air outlet opening,
said dust collecting wall means further including a dust collecting
filter attached to the surface of said dust collecting electrode
facing said passageway and an additional dust collecting electrode
of a wire mesh form, said additional dust collecting electrode
being attached to the surface of said dust collecting filter facing
said passageway and electrically connected to the first named dust
collecting electrode.
2. An air purifier as claimed in claim 1, further comprising
deodorizing means located in said passageway immediately anterior
to said air outlet opening, in which said deodorizing means in
movable in situ relative to said air outlet opening so that the
area passing the cleaned air through said deodorizing means is
variable through changing the position of the deodorizing means
relative to said air outlet opening.
3. An air purifier as claimed in claim 2, further comprising an
ionizing electrode located in the neighbourhood of said air outlet
opening and operative to be impressed with a negative high-tension
power and a grounding electrode spaced from said ionizing electrode
for ionizing to negative polarity the air being discharged from
said casing through said air outlet opening.
4. An air purifier as claimed in claim 3, in which said casing
comprises an end wall supporting thereon said dust collecting wall
means and releasable from said casing, and further comprising
switch means mounted in part on said end wall and in part on a
remaining portion of said casing for providing a releasable
electrical connection between said dust collecting electrode and an
electric power source, said electrical connection being interrupted
when said end wall is released from said casing.
5. An air purifier as claimed in claim 3, further comprising an
additional charging electrode located in said passageway
immediately posterior to said air inlet opening for connection to a
third electric terminal having a polarity which is similar to the
polarity of said second electric terminal for thereby preliminarily
charging the dust entrained in the air admitted to said passageway
through said air inlet opening.
6. An air purifier comprising a generally cylindrical casing having
an air inlet opening and an air outlet opening located
substantially centrally of the casing, dust collecting wall means
positioned within said casing and providing a continuous passageway
extending spirally between the air inlet and outlet openings in
said casing, said wall means including at least one dust collecting
electrode for connection to a first electric terminal, and at least
one charging electrode extending spirally in and along said
passageway and electrically isolated from said collecting
electrode, said charging electrode being for connection to a second
electric terminal having a polarity opposite to the polarity of the
first electric terminal for thereby establishing an electric field
between the charging and collecting electrodes so that particles of
dust entrained in air directed into said passageway through said
air inlet opening become ionized and are attracted to said dust
collecting wall means as the air is circulated through said
passageway from said air inlet opening to said air outlet opening,
and further comprising deodorizing means located in said passageway
immediately anterior to said air outlet opening, in which said
deodorizing means is movable in situ relative to said air outlet
opening so that the area passing the cleaned air through said
deodorizing means is variable through changing the position of the
deodorizing means relative to said air outlet opening.
7. An air purifier comprising a generally cylindrical casing having
an air inlet opening and an air outlet opening located
substantially centrally of the casing, dust collecting wall means
positioned within said casing and providing a continuous passageway
extending spirally between the air inlet and outlet openings in
said casing, said wall means including at least one dust collecting
electrode for connection to a first electric terminal, at least one
charging electrode extending spirally in and along said passageway
and electrically isolated from said collecting electrode, said
charging electrode being for connection to a second electric
terminal having a polarity opposite to the polarity of the first
electric terminal thereby establishing an electric field between
the charging and collecting electrodes so that particles of dust
entrained in air directed into said passageway through said air
inlet opening become ionized and are attracted to said dust
collecting wall means as the air is circulated through said
passageway from said air inlet opening to said air outlet opening,
and an ionizing electrode located in the neighbourhood of said air
outlet opening and operative to be impressed with a negative
high-tension power and a grounding electrode spaced from said
ionizing electrode for ionizing to negative polarity the air being
discharged from said casing through said air outlet opening.
Description
The present invention relates to an air purifier and, more
particularly, to an air purifier of the dust collector type adapted
to remove dust from atmospheric air.
A primary object of the present invention is to provide an improved
air purifier having an enhanced dust collection efficiency and
capable of collecting dust of relatively large particle sizes.
Another important object of the invention is to provide an improved
air purifier which meets serious space requirements such as in
buses and automobiles.
To accomplish these objects, an air purifier herein proposed is
characterized in that it operates on the principles of operation of
a centrifugal dust separator and an electrostatic dust precipitator
which per se are well known in the art.
In accordance with the present invention, the air purifier consists
essentially of a generally cylindrical casing having an air inlet
opening which is directed substantially tangentially of the casing
and an air outlet opening which is located substantially centrally
of the casing, dust collecting wall means positioned within the
casing and providing a continuous passageway helically extending
between the air inlet and outlet openings, the wall means including
at least one dust collecting electrode for connection to one
electric terminal, and at least one charging electrode helically
extending in and along the passageway and electrically isolated
from the collecting electrode, the charging electrode being for
connection to another electric terminal having a polarity opposite
to the polarity of the terminal for the collecting electrode for
thereby establishing an electric field between the charging and
collecting electrodes so that particles of dust entrained in an air
stream directed into the passageway through the air inlet opening
become ionized and are attracted to the dust collecting wall means
as the air stream is circulated through the passageway.
By reason of the increased dust collecting efficiency and the
ability of collecting relatively large dust particles, an air
purifier of the general configuration above described will provide
advantageous especially where used in a motor vehicle in which only
a limited amount of space is available for incorporating the air
purifier.
Other features and advantages of an air purifier according to the
present invention will be more apparent from the following
description taken in conjunction with the accompanying drawings in
which like reference numerals and characters designate
corresponding parts and members throughout the figures and in
which:
FIG. 1 is a cross sectional view of a first preferred embodiment of
an air purifier according to the present invention;
FIG. 2 is a side sectional view of the air purifier illustrated in
FIG. 1;
FIG. 3 is a longitudinal sectional view showing on an enlarged
scale of preferred example of an arrangement to support a charging
electrode in the air purifier illustrated in FIGS. 1 and 2;
FIG. 4 is a cross sectional view showing a second preferred
embodiment of an air purifier according to the present
invention;
FIG. 5 is a side sectional view of the air purifier illustrated in
FIG. 4;
FIG. 6 is a fragmentary perspective view showing on an enlarged
scale a preferred example of a safety arrangement to be
incorporated into the air purifier according to the present
invention,
FIG. 7 is a schematic view showing an electric circuit including a
switch means to be incorporated in the safety arrangement
illustrated in FIG. 6;
FIG. 8 is a cross sectional view showing a third preferred
embodiment of an air purifier according to the present invention;
and
FIG. 9 is a side sectional view of the air purifier illustrated in
FIG. 8.
Reference will now be made to the drawings, first to FIGS. 1 and 2
which illustrate a first preferred embodiment of an air purifier
according to the present invention.
As seen in FIGS. 1 and 2, the air purifier embodying the present
invention includes a generally cylindrical casing which is
designated in its entirety by reference numeral 20. The casing 20
is formed of an electrically non-conductive material and comprises
a generally cylindrical wall 22 and upper and lower end walls 24
and 26, respectively. The casing 20 has formed in its cylindrical
wall 22 and opening 28 through which an air inlet duct 30 projects
into the casing 20 substantially tangential to the inner surface of
the cylindrical wall 22 as seen in FIG. 1. Approximately centrally
of the upper wall 24 of the casing 20 is formed an opening 32 which
is in communication with an air outlet duct 34.
Within the casing 20 is positioned a dust collecting electrode 36
which spirals inwardly from a leading end 30a of the air inlet duct
30 toward the center of the casing 20, terminating substantially in
alignment with the air outlet opening 32 in the upper end wall 24
of the casing 20. The outermost segment of the dust collecting
electrode 36 is attached to the inside of the cylindrical wall 22
along a portion thereof, and comprises a radially outer layer 38, a
radially intermediate layer 40 of a dust collecting filter attached
to the inner surface of the outer layer 38, and an electrically
conductive porous or meshed radially inner layer 42 attached to the
inner surface of the intermediate layer 40. The collecting
electrode 36 extends for substantially one complete spiral
revolution within the casing 20 having the configuration described
above, and merges at the end 30a with a portion thereof which
spirally extends further inward, but has an altered configuration
which will now be described. The inner portion of the dust
collecting electrode 36 comprises an electrically conductive
intermediate layer 38' electrically connected to the outer layer
38, a pair of layers 40' and 40" of a dust collecting material
attached to the radially outer and inner surfaces, respectively, of
the intermediate layer 38'. and a pair of electrically conductive
porous or meshed outer layers 42' and 42" attached to the radially
outer and inner surfaces of the layers 40' and 40", respectively,
of the dust collecting material, the layers 40" and 42" thus
extending continuously from the layers 40 and 42, respectively. The
layers 40, 40' and 40" of dust collecting material are preferably
formed of unwoven cloth made of synthetic fibres such as glass
fibres while the electrically conductive porous or meshed layers
42, 42' and 42" are formed of, for example, wire meshes. The
electrically conductive layers 38 and 38' may be sheet metals. The
electrically conductive layers 38 and 38' are electrically
connected to the electrically conductive layers 42, 42' and 42"
through an electrically conductive plate 44.
The dust collecting electrode 36 thus configured defines a
continuous passageway 46 spirally extending from the leading end
30a of the air inlet duct 30 to a substantially central portion 48
of the interior of the casing 20, thus providing unrestricted
communication between the air inlet duct 30 and the air outlet duct
34, as seen in FIG. 1.
A suitable number of charging electrodes 50, shown in FIG. 2 as
being two in number by way of example, spirally extend
substantially centrally within the passageway 46 and terminate at
their inner ends in the vicinity of the central portion 48 of the
interior of the casing 20. The charging electrodes 50 are spaced
apart from each other along the axis of the casing 20 and are
supported from the upper end wall 24 of the casing 20 by a number
of electrically conductive rods or wires 52 as seen in FIG. 2. The
charging electrodes 50 may have their outer ends located
immediately downstream of to the leading end 30a of the air inlet
duct 30 or, where desired, the electrodes 50 may have their outer
ends appropriately spaced from the leading end 30a of the air inlet
duct 30, as in the embodiment illustrated in FIG. 1. Where the
charging electrodes 50 are disposed in a manner illustrated in FIG.
1, an additional charging electrode 54 in a rod form may be located
at the entrance of the passageway 46 for preliminarily charging the
or ionizing the dust particles before the air to be cleaned reaches
the electrodes 50. In this instance, the electrode 46 serves to
augment the electric field between the electrodes 50 and the dust
collecting electrodes 36 on both sides thereof.
Wiring arrangements are made so that the charging electrodes 50 and
54 are energized to a polarity opposite to the polarity of the dust
collecting electrode 36. Thus, one of the conductive rods or wires
52 is electrically connected to a source (not shown) of high dc
voltage through a lead 56 and a joint 58 which is attached to the
upper end wall 24 of the casing 20, while the dust collecting
electrode 36 or more particularly the electrically conductive
layers 38 and 38' are connected to ground through a line 60. It is,
in this instance, preferable that the charging electrode 54 be
supplied with a dc voltage which is equal to or higher than the
voltage applied to the spiral charging electrode 50. The wiring
arrangements above described charge the dust particles to a
positive polarity but, where desired, the arrangement may be
reversed so that the dust collecting electrode 36 is connected to
the positive electrical source terminal and the charging electrodes
50 and 54 are connected to ground for charging the dust particles
to a negative polarity. The conductive rods or wires 52 excepting
the one connected to the lead 56 are supported at the upper end
wall 24 of the casing by means of retainers 62, each comprising a
rivet 62a and a spacer 62b by which the rod or wire 52 is
adjustably attached to the end wall 24.
Where desired, the lower end wall 26 of the casing 20 may be formed
with an opening 64 located in alignment with the air outlet opening
32 in the upper end wall 24 for allowing relatively heavy dust
particles to drop out of the casing 20 before the cleaned air is
discharged from the air outlet opening 32. In this instance, a dust
reservoir 66 may be releasably supported at the lower surface of
the lower end wall 26 of the casing 20 so that dust particles
dropping from the interior of the casing 20 are deposited in the
reservoir 66. The lower end wall 26 and the adjacent dust
collecting electrode 36 are releasably connected to the cylindrical
wall 22 of the casing 20 so that the end wall 26 and the dust
collecting electrode 36 can be removed from the casing 20 for
dislodging the dust deposited on the dust collecting layers 40, 40'
and 40" of the dust collecting electrode 36.
FIG. 3 illustrates a preferred example of the joint 58 through
which a conductive rod or wire 52 is connected to the lead 56. As
seen in FIG. 3, the joint 58 comprises a flanged, internally
threaded retaining member 68 which is received in the upper end
wall 24 of the casing 20 with its flange fast on the upper surface
of the end wall 24 and its inner end projecting into the interior
of the casing 20. The retaining member 68 serves as a washer and is
secured to the end wall 24 by means of a snap ring 70 which is fast
on the inner surface of the end wall 24. The conductive rod or wire
52 is threaded at its upper end portion 52a and screwedly received
in the retaining member 68 with its tip projecting from the upper
end of the retaining member 68. An internally and externally
threaded member 71 securely receives in its internally threaded
bore the upper end portion 52a of the rod or wire 52 and rests on
the upper face of the retaining member 68. The rod or wire 52 is
connected at its end to the lead 56 through a snap connection 72
which may be configured in the form of a ball and socket joint. The
threaded member 71 and the snap connection 72 are enclosed within a
cup-like cap member 74 having an internally threaded portion by
which the cap member 74 screws onto the threaded member 71. The cap
member 74 has formed at its top an aperture 74a through which the
lead 56 passes through the cap member 74. Where desired, the cap
member 74 may be formed with a projection 74b on its inner surface
for engagement with the upper surface of the threaded member 71.
The retaining member 68, threaded member 71 and cap member 74 are
all formed of electrically insulating materials. A joint
arrangement of the nature above described is merely for the purpose
of illustration and, as such, is subject to various modifications
and changes where desired.
Where the air purifier thus far described is placed in practical
use, it is important that the same be arranged in combination with
a blower or suction fan for achieving forced circulation of air
through the air purifier. When, thus, the fan associated with the
air purifier is driven and the charging electrodes 50 and 54 are
energized from the source of high-tension dc., voltage, air
entering the passageway 46 from the air inlet duct 30 is passed
through the electric field established between the electrode 54 and
the dust collecting electrode 36 on both sides of the former.
Particles of dust contained in the stream of air become ionized to
a positive polarity and then move into the electric field built up
on both sides of the spiral electrode 50. The dust particles are
then attracted to the grounded electrically conductive layers of
the dust collecting electrode 36 and are deposited on the
intermediate dust collecting layers 40, 40' and 40" of the
electrode 36 as the air flows through the spiral passageway 46
toward the substantially central portion 48 of the casing 20.
It is generally known in the art that in an electrostatic dust
precipitator having a straight air flow passageway, the dust
collecting efficiency decreases if when the dust particles are
moved through the length of the passageway in the time period which
is shorter than the time in which the ionized particles can be
moved to the dust collecting electrode by the electrostatic
attraction. If air to be cleaned were passed through the passageway
at such a high velocity, no dust particles of any size could be
satisfactorily trapped by the dust collecting electrode in a
conventional air purifier using the electrostatic dust collection
principle alone. Since, however, in the air purifier according to
the present invention, air to be cleaned is passed therethrough in
a spiral path, dust particles contained in the air stream are
subjected to centrifugal force as the air circulates through the
passageway 46, so that those particles which could not be collected
by dust collecting electrode 36 by the electrostatic attraction
alone can be moved to the electrode 36 under the influence of
centrifugal force even though air passes at a high velocity through
the spiral passageway 46. It is, moreover, said that dust particles
of sizes larger than approximately 20 microns in diameter can not
be collected by means of electrostatic attraction alone. In an air
purifier according to the present invention, however, dust
particles of sizes larger than 20 microns can be satisfactorily
collected by the dust collecting electrode 36 even though the air
is passed at a considerably high velocity through the air purifier,
because the larger the particles are the greater the centrifugal
forces imparted to the particles. An air purifier according to the
present invention thus has outstanding features which include:
a. High dust collecting efficiency achieved essentially
irrespective of the velocity and rate of flow of air passing
through the air purifier and of the sizes of the dust particles
contained in the stream of air.
b. The dust collected is securely trapped by the dust collecting
material.
c. Minimum efforts are required for maintenance and servicing of
the air purifier and for exchange of parts.
d. Compact overall configuration resulting from the spirally
configured air passageway.
It has been assumed in the description of the embodiment shown in
FIGS. 1 and 2 that the electrically conductive layers 38 and 38'
are electrically connected to the porous or meshed electrically
conductive layers 42, 42' and 42" as through the conductive plate
44, but they may be electrically isolated where desired. In this
instance, the layers 42, 42' and 42" should be formed of an
electrically non-conductive material and at the same time the plate
44 should be removed from the arrangement illustrated in FIG.
2.
Where desired, moreover, a deodorizing filter 69 may be located
between the passageway 46 and the air outlet opening 32 for
removing unpleasant odors from air to be discharged from the air
outlet duct 34. A more detailed configuration of such a deodorizing
arrangement is illustrated in FIGS. 4 and 5 which show a second
preferred embodiment of the air purifier according to the present
invention.
Referring to FIGS. 4 and 5, the deodorizing filter 69 is configured
as generally cylindrical and has an open upper end which is in
alignment with the air outlet openings 32 in the upper end wall 24
of the casing 20. The use of a deodorizing filter in an air
purifier is in itself well known in the art and it has been an
ordinary practice to have the filter fixedly held in place on, for
example, the casing of the air purifier. Where the deodorizing
filter is thus fixedly mounted on casing, bad-smelling materials
are accumulated on a limited area of the filter located in the path
of air to be discharged from the air outlet opening 32, and the
remaining area of the filter is kept intact. In the case of the air
purifier configuration illustrated in FIGS. 4 and 5, air containing
bad odors is passed locally through the area indicated as 69a of
the filter 69 with the remaining area 69b kept intact throughout
the use of the filter. This localized accumulation of materials
will result in degraded deodorizing performance and a shortened
life of the filter. Replacing the filter with a new one from time
to time will require a disproportionate amount of time and labour
and is therefore objectionable from an economical point of
view.
For the purpose of eliminating this drawback, the lower end wall 26
of the casing 20 is formed with an opening 77 which is in alignment
with the lower end of the deodorizing filter 69 and the opening 77
is closed by a closure 79 which is rotatably mounted on the lower
surface of the lower end wall 26 of the casing 20 by means of
fittings 81. The deodorizing filter 69 is securely connected at its
lower end to the upper surface of this closure 79 and is thus
rotatable about its axis within the casing 20 together with the
closure 79. The angular position of the filter 69 relative to the
path of air to be discharged from the air outlet opening 32 is thus
variable by turning the closure 79 on the lower end wall 26 of the
casing 20 so that smell-containing materials can be accumulated
substantially uniformly throughout the area of the filter 69 by
turning the filter 69 about its axis from time to time. To
facilitate turning of the closure 79, a knob 79a may be formed or
mounted centrally on the lower surface of the closure 79, as
shown.
In FIGS. 4 and 5, the air purifier embodying the present invention
is shown as incorporating only one charging electrode 50 extending
substantially centrally through the passageway 46 from the air
inlet opening 28 to the air outlet opening 32, although more than
one electrode 50 may be employed if desired.
As previously mentioned, the lower end wall 26 of the casing 20 is
arranged so as to be detachable together with the dust collecting
electrode 36 to facilitate removal of dust particles deposited on
the layers 42, 42' and 42" of the dust collecting material 36. If,
in this instance, the lower end wall 26 of the casing 20 and the
dust collecting electrode 36 supported by the end wall 26 are
removed from the casing 20 with the charging electrode 50
inadvertently left energized by the high-tension power source (not
shown), a serious danger will be incurred on the operator. FIG. 6
illustrates an embodiment of an air purifier according to the
present invention which eliminates such a danger.
Referring to FIG. 6, the cylindrical wall 22 of the casing 20 has
formed at its circumferential edge portion adjacent the lower end
wall 26 a pair of projections 76 and 76' extending radially outward
from the cylindrical wall 22 and joined together at their ends by a
wall portion 78. Spaced contact elements 80 and 80' are mounted on
the inner faces of these projections 76 and 76', respectively in a
manner to face each other at a certain spacing therebetween. The
contact elements 80 and 80' are electrically connected to leads 82
and 82', respectively. As seen in FIG. 7, the lead 82 is connected
to the source 84 of the dc., high-tension voltage through an air
purifier actuator switch 86 and a fuse 88. The other lead 82' is
connected through a booster transformer 90 to the charging
electrode 50 of the air purifier.
On the other hand, the lower end wall 26 of the casing 20 is formed
with a radial projection 92 which is so located as to be in
alignment with the projections 76 and 76' of the cylindrical wall
22 when the lower end wall 26 is attached in its working position
to the cylindrical wall 22. The projection 92 carries on its upper
face an electric connector element 94 which is connectably received
between the spaced contact elements 80 and 80' when the lower end
wall 26 is assembled to the cylindrical wall 22 for thereby
completing an electric path between the high-tension power source
84 and the charging electrode 50.
Through provision of the switching arrangement above described, the
charging electrode 50 can be reliably disconnected from the
high-tension power source 84 even though the air purifier actuating
switch 86 is inadvertently left closed when the lower end wall 26
is removed together with the dust collecting electrode 36 for the
purpose of purging the collecting electrode 36.
It is empirically known that the negative ions in atmospheric air
act to tranquilize human nerves while positive ions act to the
contrary. FIGS. 8 and 9 illustrate a fourth preferred embodiment of
the air purifier according to the present invention arranged to
utilize such a phenomenon.
Referring to FIGS. 8 and 9, the air purifier includes in addition
to the parts and elements incorporated in the embodiment shown in
FIGS. 4 and 5, an ionizing electrode 96 which is located in the air
outlet opening 32 in the upper end wall 24 of the casing 20. The
ionizing electrode 96 is shown as being in a needle form and is
supported by an outer casing 99 through a support 100 of an
electrically conductive material. The support 100 is connected to a
source (not shown) of a negative high-tension d.c. voltage for
impressing a negative high-tension potential on the ionizing
electrode 96 so that air being discharged through the air outlet
opening 32 is ionized to a negative polarity. The embodiment above
described is thus adapted not only to clean and deodorize the air
but to ionize the air to the negative polarity such that it will
soothe the human nerves. Where the air purifier having such
features is installed in a motor vehicle, the same will contribute
to safe driving while supplying satisfactorily cleaned air.
* * * * *