Abstrict An air diffuser is provided, preferably for an air curtain generator,
which consists of a frame within which are located a plurality of
louvres. The louvres are striated and rotatably adjustable about
respective axes of rotation. To provide for this rotatable adjustment
the louvres are mounted on splined shafts which are received in
splined receptacles. The splined receptacles are made in nesting
sections which are releasably connected together to provide for
the loosening of the shafts and adjustable rotation of the shafts
and adjustable rotation of the same to positions whereat the shafts
and thereby the louvres are locked in position. Some of the shafts
are in parallel with the others. Some of the shafts are further
mounted in axial extension of other of the shafts. The shafts of
louvres which are in axial extension of one another are in nesting
relationship and for this purpose are provided with polygonal cross-sections
which prevent rotation of a relative nature therebetween.
Claims What is claimed is:
1. Apparatus comprising a rotatable louvre having an axis of rotation
and being adapted to control a flow of air, and means to lock said
louvre selectively in one of a plurality of angularly displaced
positions relative to said axis, said positions being regularly
spaced about said axis, and forming a circle around said axis, said
louvre having a surface of striated configuration to improve mechanical
performance and maintain appearance.
2. Apparatus as claimed in claim 1 comprising air curtain generating
means including a casing provided with a vent and means to discharge
air through said vent to form an air curtain, said louvre being
supported at said vent to control the discharge of air.
3. Apparatus comprising a rotatable louvre having an axis of rotation
and being adapted to control a flow of air, and means to lock said
louvre selectively in one of a plurality of angularly displaced
positions relative to said axis, said positions being regularly
spaced about said axis, and forming a circle around said axis, said
means comprising a splined shaft supporting said louvre and a splined
receptacle means defining a splined receptacle for receiving said
splined shaft, said receptacle means including relatively displaceable
sections and connecting means for holding the sections together
to lock said shaft in a selected position.
4. Apparatus as claimed in claim 3 wherein said displaceable sections
have a nesting conformation for being guided together to define
said splined receptacle.
5. Apparatus as claimed in claim 4 wherein said connecting means
includes at least one bolt engaging the displaceable sections to
hold the same together.
6. Apparatus as claimed in claim 4 further comprising a frame defining
an opening for confining the flow of air, said louvre being arranged
in transverse position in said opening.
7. Apparatus as claimed in claim 6 comprising a plurality of further
louvres in parallel with the first said louvre, and means to lock
said further louvres in respective angularly displaced positions.
8. Apparatus as claimed in claim 6 comprising a further louvre
in axial extension of the first said louvre, said further louvre
including a shaft in endwise nesting relation with the shaft of
the first said louvre and being rotationally locked thereto so that
the louvres are rotatable together.
9. Apparatus as claimed in claim 8 wherein the first said shaft
includes a receptacle of polygonal cross-section and the shaft of
said further louvre is of matching polygonal cross-section but is
tapered to facilitate insertion into the polygonal receptacle.
10. Apparatus as claimed in claim 9 comprising end caps on said
louvres and supporting said shafts.
11. Apparatus as claimed in claim 6 comprising a shaft on said
louvre and rotatably accommodated in said frame.
12. Apparatus as claimed in claim 9 comprising air curtain generating
means including a casing provided with a vent and means to discharge
air through said vent to form an air curtain, said louvre being
supported at said vent to control the discharge of air.
13. Apparatus as claimed in claim 3 wherein the positions are spaced
at a distance in the range of from about 1 to 15 degrees. Description FIELD OF INVENTION
This invention relates to structures for controlling air flow and
more particularly to arrangements of louvres which permit the rotatable
adjustment of the same. The invention relates particularly to air
diffusers for controlling the flow of air especially in association
with air blower arrangements for producing air screens or curtains.
BACKGROUND OF THE INVENTION
U.S. Pat. No. 4,450,755 which issued on May 29, 1984 discloses
a blower apparatus which is especially suitable for the generation
of an air curtain, screen or barrier. The apparatus described in
this patent includes a blower having a plurality of blades arranged
in cylindrical disposition. A guide encircles the blower but extends
axially beyond the blower to provide for the generation of an air
stream, the width of which is greater than that of the blower. A
deflector or interceptor plate in the form of a scroll is arranged
to prevent air from circulating in axial direction back into the
blower and is provided to improve the effectiveness of generation
of the air stream which flows tangentially out of the blower apparatus
through a vent through which the air stream is discharged.
It has now been found that it may be desirable to control the flow
of the air discharged through the abovementioned vent as well as
in other type of apparatus. Such ability provides for a more particular
control of the disposition of the air curtain and also provides
for situations wherein the vent in the blower apparatus may not
be appropriately arranged to direct the air curtain in a particularly
desired direction. For this purpose it has been found, in accordance
with the present invention, that it is desirable to provide a plurality
of adjustable louvres at the abovementioned vent to provide for
the control of the flow of air therethrough.
Venting arrangements have long been known and some of these arrangements
are shown by way of example in U.S. Pat. Nos. 1,725,353; 1,753,587;
1,872,794; 3,180,246; 3,270,657; and 3,601,034.
In U.S. Pat. No. 1,725,353, R. M. Hinrich discloses an adjustable
air diffuser in which an arrangement is provided for retaining each
of a plurality of blades in different positions of adjustment independently
of the other blades. For this purpose elongated loops are pivotally
connected to the blades and are held by a clamping arrangement associated
therewith. Such an arrangement results in the accumulation of dirt
and grime at a location whereat these contaminants are prevalent.
F. M. Young discloses in U.S. Pat. No. 1,753,587 the use of air
deflectors adjustably mounted to control the flow of a current of
air which has been impelled by a fan propeller. These deflectors
are mounted at one of their edges and can be adjusted in order to
control the flow of air. The nature of the adjustment is not set
forth in any detail and appears to be a simple matter of manual
control.
In U.S. Pat. No. 1,872,794, Q. G. Noblitt et al illustrate a plurality
of pivotally mounted shutters. These shutters are utilized to direct
air flow. These shutters appear to be manually controllable and
no description is offered of the manner in which these shutters
are fixed in position.
In U.S. Pat. 3,180,246, E. H. Johnson reveals an air control device
such as a diffuser or the like. Therein are provided a number of
shutter arrangements in which provision is made for rotational adjustment
of the same. To retain the blades in their positions a frictional
device is employed involving the use of a pressure plate. As will
become apparent hereinafter such an arrangement is substantially
different from what is offered in accordance with the present invention.
In U.S. Pat. No. 3,270,657, R. C. Jaye shows an air outlet having
angularly adjustable louvres. The louvres are adjustably accommodated
in receptacles wherein they are retained by a friction fit which
is enhanced by the particular construction of the louvres.
In U.S. Pat. No. 3,601,034, J. Thorne reveals a diffuser having
a frame made of L-shaped members with a plurality of louvres extending
between the L-shaped members. The louvres have pins extending through
openings in the frame members with resilient fingers engaging the
louvre pins and securing the louvres against inadvertent rotation
thereof.
None of the aforesaid louvre arrangements nor any other structures
known to me are anticipatory of the concept developed in accordance
with the invention and described hereinbelow.
SUMMARY OF INVENTION
It is an object of the invention to provide improved louvre arrangements
and air diffusers compared with the abovenoted prior art arrangements.
It is another object of the invention to provide an improved louvre
support system which enables louvres to be rigidly held in fixed
position at incrementally spaced positions about an axis of rotation.
It is a further object of the invention to provide an improved
air diffuser control capable of arranging louvres in a multitude
of fixed positions.
Yet another object of the invention is to provide an improved louvre
control providing for rigid support while being nevertheless adapted
for facilitating installation and adjustment.
In achieving the above and other of its objectives, there is provided
in accordance with the invention apparatus comprising a rotatable
louvre having an axis of rotation and being adapted to control a
flow of air. In connection therewith there is provided an arrangement
to lock the louvre selectively in one of a plurality of angularly
displaced positions relative to the aforementioned axis. Preferably
these positions are regularly spaced about the axis. In a preferred
embodiment these positions form a circle about this axis.
According to a feature of the invention each louvre has a surface
of striated configuration to increase strength to weight ratio.
In further accordance with a preferred embodiment the arrangement
to lock the louvre in the various positions includes a splined shaft
supporting the louvre and a splined receptacle for receiving the
splined shaft. The receptacle is preferably provided with a plurality
of relatively displaceable sections which are connected by connecting
devices for holding the sections together to lock the associated
shaft in a selected position.
In accordance with a feature of the invention the displaceable
sections mentioned above have a nesting conformation for being guided
together to define the splined receptacle. This arrangement will
be described in greater detail hereinbelow.
In further accordance with the invention there is provided a frame
defining an opening for confining the flow of air, the louvre or
louvres being arranged in transverse positions in the opening and
being supported by the frame. The louvres may be generally considered
as being in parallel with one another. Some of the louvres are in
axial extension of other of the louvres. The shafts in endwise relationship
with one another or in axial extension of one another are provided
with shafts which are in endwise nesting relationship but which
are rotationally locked together so that the louvres are adjustable
together when they are in this endwise axial extension of one another.
In a preferred embodiment the shafts which are in nesting relationship
are of polygonal cross-section and fit into receptacles of polygonal
cross-section in the mating or nesting shaft. The polygonal shaft
which fits into the polygonal receptacle is tapered to facilitate
insertion into the polygonal receptacle.
As will be shown in greater detail hereinbelow the louvres are
provided with end caps upon which the aforementioned shafts are
mounted. Moreover, reference will be made in greater detail hereinbelow
to the provision of air curtain generating arrangements including
casings provided with vents at which the abovementioned louvres
are supported.
The above objects and advantages of the invention will be more
readily understood in conjunction with the detailed description
which follows hereinafter as illustrated in the accompanying drawings.
BRIEF DESCRIPTION OF DRAWING
In the drawing:
FIG. 1 is a cross-sectional view of an air curtain generator provided
with a louvre arrangement in accordance with the invention;
FIG. 1(a) illustrates a fragmentary portion of the arrangement
of FIG. 1 illustrating another mounting posture for the air diffuser
of the invention;
FIG. 2 is a bottom view of the air diffuser of the invention, partially
broken away to illustrate that the air diffuser may be designed
with various lengths;
FIG. 3 is a cross-sectional view taken along line 3--3 of FIG.
2;
FIG. 4 is an enlarged view of a detail of the construction of FIGS.
2 and 3 illustrating the nesting relationship between the shafts
of louvres arranged in endwise extension of one another in accordance
with the invention; and
FIG. 5 is a cross-sectional view taken of a louvre mounting arrangement
along line 5--5 of FIG. 4.
DETAILED DESCRIPTION
FIG. 1 illustrates at 10 the air blower arrangement disclosed in
U.S. Pat. No. 4,450,755 which issued May 29, 1984. It includes a
casing 12 having an air inlet opening 14 provided with a screen
16 to prevent the entry of solid objects such as insects and the
like. In the chamber 18 enclosed by the casing 12 is a blower diagrammatically
illustrated at 20 consisting of a plurality of vanes arranged in
a cylindrical form. Also present in the chamber 18 is a scroll-shaped
member 22 having the function of directing air flow towards a vent
or opening 24 covered by a screen 26. A deflector plate 28 having
the function of preventing return of air axially into the blower
is furthermore provided. It is mounted on a support 30.
In accordance with the invention there is provided the diffuser
32 consisting of a plurality of louvres such as shown at 34,36 and
38. These louvres are adjustable and operate within the throat 40
of casing 42 to control the direction of air flow thereby to control
the disposition of the air curtain formed by the discharge of air
through the opening 24. Casing 40 is mounted by flanges 44 and 46
on the bottom 48 of casing 12 by means of appropriate fastening
elements such as bolts 50.
FIG. 1(a) illustrates a slightly different disposition of the air
diffuser 32 in that the wall or casing 42 thereof extends inwardly
into the casing 12. The vanes such as indicated at 34,36 and 38
however continue to perform the function of controlling air flow
during the exit of air from the interior chamber of the casing 12.
As will be shown this is effected by enabling a rotation of the
louvres into a fixed position whereat they are locked according
to a feature of the invention as will become more apparent hereinafter.
FIGS. 2-5 illustrate the preferred version of air diffuser provided
in accordance with the invention and illustrated in combination
with an air blower arrangement in FIGS. 1 and 1(a). The air diffuser
of the invention includes a plurality of louvres. As indicated in
FIGS. 1 and 1(a) there are included louvres 34,36 and 38. These
louvres are in parallel with one another as are additional louvres
60,62 and 64. There may be any number of louvres provided in axial
extension of one another and the length L of the air diffuser arrangement
of the invention may be varied widely as required by the air flow
which is to be controlled. More particularly, louvre 34 is in axial
extension of louvre 60 and vice versa as are pairs of louvres 36
and 62 and 38 and 64. These louvres are accommodated within casing
42 which is provided with bottom flanges 66 and 68 as well as end
flanges 70 and 72. These flanges may be provided with openings such
as indicated at 74 to provide for the use of fastening elements
such as bolts by means of which the air diffuser of the invention
is physically associated with and mounted on an associated piece
of apparatus such as illustrated in FIGS. 1 and 1(a).
A portion of flanges 70 and 72 is broken away to illustrate shafts
or pins 76 and 78. These are illustrative of the pins or shafts
upon which the louvres are mounted for free rotation. At the other
ends of the louvres are provided mounting arrangements by means
of which the louvres are incrementally rotated about their respective
axes, one such axis being illustrated at 80 and being common to
louvres 34 and 60. Pins 76 and 78 are respectively mounted in end
walls 82 and 84, these end walls being part of the casing of the
air diffuser. The walls between the end walls 82 and 84 are shown
at 86 and 88 to complete the definition of an air flow passage 90
by means of which air exits in the form of a curtain from the chamber
12 via vent 24 (see FIG. 1).
Between walls 86 and 88 extends a separator or support wall 92.
It consists of sections 94 and 96. Section 94 is of trapezoidal
conformation and includes sloped end walls 98 and 100. Section 96
defines a trapezoidally-shaped receptacle 102 having sloped walls
104 and 106. Wall 98 forms a camming surface for wall 104 while
wall 100 forms a camming surface for wall 106. These camming surfaces
enable the sections 94 and 96 to be brought together in nesting
relationship. The purpose of this is to provide for the uniting
of receptacle sections 110 and 112, 114 and 116, and 118 and 120.
These splined receptacle sections cooperate to form circular splined
receptacles which accommodate splined shafts or pins 122,124 and
126. As will be shown these splined shafts support louvres 34,36
and 38.
The purpose of the splined shafts and splined receptacles is to
permit a controlled incremental variation of the rotational disposition
of the various louvres. The splines may be dimensioned for example
so that the louvres may be incrementally varied in steps having
an angular magnitude of from about 1 to 15 degrees. Sections 94
and 96 are held together by fastening elements such as bolts 130
and 132. These bolts fit freely through bores 134 and 136 to be
engaged in threaded receptacles 138 and 140. By loosening the bolts
the sections 94 and 96 may be given a relative movement away from
one another to loosen the grip of the receptacles on the associated
splined shafts 122,124 and 126 so that the louvres 34,36 and 38
may be rotated independently and separately to any desired degree
to give them an appropriate posture in the throat or passage. Thereafter
the bolts 134 and 136 may be tightened to bring sections 94 and
96 together thereby to clamp the splined receptacles together to
grip the splined shafts tightly therein thereby to fix the relative
postures of the associated louvres.
As mentioned hereinabove, louvre 60 is in axial extension of louvre
34, louvre 62 is in axial extension of louvre 36, and louvre 64
is in axial extension of louvre 38. The connection between these
louvres is illustrated in FIG. 4. Therein is seen by way of example
that shaft or pin 150 is accommodated within a bore 152 axially
aligned within for example shaft 122 wherein the bore is axially
aligned. As appears in FIG. 3 the bore 152 as well as the pin 150
is provided with a polygonal cross-section as indicated at 154.
Since the pin and receptacle receiving the same have matching polygonal
configurations, rotation of the shaft 122 will cause a concomitant
rotation of the shaft or pin 150. Thus, for example, louvre 34 and
louvre 60 will rotate together upon adjustment of either of these
louvres. The same is true of pairs of louvres 36 and 62 and 38 and
64 although one pair of louvres may be rotatev to a greater or lesser
degree than the other pairs of louvres.
Pins or shafts 122 and 150 (as well as the other corresponding
pins and shafts are mounted on end caps 160 and 162. The ends of
the corresponding louvres are received in and supported by these
end caps which may be for example fabricated of plastic or hard
rubber or the like.
The shapes of these end caps are illustrated more specifically
in FIG. 5 wherein it is seen that these end caps are of oval shape
and are provided with oval openings 168 within which are accommodated
the ends of the respective louvres. Also illustrated in FIG. 5 are
the striations 170 with which the surfaces of the respective louvres
are scored. These striations are preferably longitudinally disposed
along the respective louvres and are parallel to the corresponding
axes such as the axis 80 (see FIG. 2) which constitutes the various
axes of the pairs of louvres described hereinabove. The striations
have a depth of from about 005-030 inches. The striated surface
makes for a stiffer blade with less weight than an unstriated blade.
In addition, the striations serve to aid in the perception of which
direction the louvres are tilted and how they are inclined. The
provision of these striations constitutes another of the features
of the invention whereby a more efficient and effective air control
is provided.
From the above it will be seen that in accordance with the invention
there is provided an apparatus which includes a rotatable louvre
having an axis of rotation and being adapted to control a flow of
air, there being furthermore provided an arrangement to lock the
louvre selectively in one of a plurality of angularly displaced
positions relative to the axis. It will also be noted that these
positions are regularly spaced about the aforementioned axis and
that the positions preferably form a circle around this axis. It
has also been noted that the louvres have surfaces of striated configuration
to improve mechanical performance and appearance.
There will now be obvious to those skilled in the art many modifications
and variations of the structure set forth hereinabove. These modifications
and variations will not depart from the scope of the invention if
defined by the following claims. |