[0001] This invention relates to a ventilation damper assembly to be mounted in a cabinet,
a ventilation duct or a wall opening and comprising a number of substantially rectangular
damper blades of wing-shaped cross-sectional profile mounted rotatably with parallel
axes of rotation between opposite frame members in a substantially rectangular damper
frame, and wherein said opposite frame members are provided with bearings for journals
secured in the damper blades, said journals being in engagement with a drive mechanism
by which the damper blades can be moved between a closing portion and an opening position.
[0002] Dampers of this type are used particularly as air volume control and damping means
as well as mixing dampers when mounted in ventilation ducts of rectangular cross-section
or in wall openings or openings in side walls or end walls of cabinets, for instance
for air conditioning control units in air conditioning systems. Beyond a reliable
closing function with respect to tightness and a movement of the damper blades which
as far as possible is free from play and noise it is a purpose to create a simple
and sturdy design of such damper blades with the lowest possible costs of production.
[0003] To obtain sufficient tightness in the closing position known dampers of the above
mentioned kind are usually provided - beyond tightening strips along the longitudinal
'edges of each damper blade - with special, lateral tightening members secured to
said frame members, such -as disclosed in DE-A-2,342,531 and in CA-A-804,873, but
thereby the damper construction is made considerably more complicated and expensive.
[0004] From GB-A-1085492 it is known to provide blades of adjustable louvres with a U-shaped
holder or clip fixed to the end of a blade to be resiliently compressible towards
the blade in order to allow turning of the blade relative to a jamb of a. metal window
frame on which a continuous protruding beading is formed to make the louvre weathertight
when closed.
[0005] From GB-A-2039361 and US-A-3783768 it is known to provide the outer contours of opposite
sides of frame members facing the flow area of a damper with a separate resilient
lining or a flexible spring-like member with a substantially convex cross-sectional
shape, whereby the minimum distance between the frame members will be aligned with
the axes of the damper blades.
[0006] It is an object of the invention to provide for most applications a sufficiently
reliable, lateral tightness in a simple manner without using particular tightening
or lining members and without noticeably reducing the movability of the damper blades.
According to the invention a damper assembly of the kind set forth is characterized
in that the opposite sides of said frame members facing the flow passage area of the
damper has a substantially convex cross-sectional shape with the minimum distance
between the frame members aligned with the bearings of the journals of the damper
blades, and in that the end portions of each damper blade comprise a curved edge portion
facing the frame members.
[0007] By this construction each damper blade is in its closing position caused to tightly
engage said frame members throughout the length of said end portions, while outside
the closing position there is only a punctiform engagement between the end portions
of the damper blade and said two frame members, the two engagement points being diametrically
opposite on either side of the bearings for the journal of the damper blade. During
the movement of the damper blade said engagement points follow a circular path around
the bearing.
[0008] According to the invention the substantially convex cross-sectional shape may be
obtained by providing the frame members with slight bendings in relation to a plane
along parallel bending lines delimiting a central strip of a width corresponding to
the diameter of the bearings for the journals of the damper blades.
[0009] Tests have shown that in connection with ordinary, longitudinal tightening lobes
on the damper blades the present invention provides for achieving in the closing position
a leakage tightness of. the same magnitude as that obtained by separate lateral tightening
members on the frame members.
[0010] In the following the invention is explained in detail with reference to the schematical
drawings, in which
[0011] Figs. 1 and 2 illustrate an embodiment of a' ventilation damper assembly according
to the invention, in a view perpendicular to the flow passage area and in a perspective
view, resp., while Figs. 3 and 4 illustrate two longitudinal sections perpendicular
to each other of the portion of a damper blade in the damper assembly in Figs. 1 and
2 engaging a frame member in the damper frame.
[0012] The damper assembly shown in Figs. 1 and 2 is mounted in a rectangular, in the present
case almost square damper frame comprising frame members 1 to 4 made from bent sheet
profiles of a substantially flat, U-shaped cross-section, so that either frame member
as shown at 5 and 6 for the frame member 1 is provided with edge flanges to secure
the damper frame either to a ventilation channel having the same flow passage area
and cross-sectional shape, to a wall opening or to an opening in the side or end wall
of a cabinet, for instance a central unit in an air conditioning system in which one
or more fans, air humidifiers, filters and/or heating members may be located.
[0013] In the illustrated embodiment four damper blades 7 to 10 of wing-shaped, cross-sectional
profile are rotatably mounted in the damper frame with parallel axes of rotation between
the two opposite lateral frame members 1 and 2, a journal 12 being inserted in an
end portion 11 at either end of each damper blade, said journal being positioned with
sliding fit in a bushing 13 drawn up in the sheet blank of the frame member as shown
in Figs. 3 and 4. To neutralize sheet deformation around the drawn bushings, linings
made from a hard plastic, for instance nylon, may be mounted in said bushings.
[0014] In Figs. 1 and 2 the damper blades 7 and 10 are shown in a central position between
a closing position in which the damper blades extend transverse to the flow direction
and block the flow passage area, and an opening position in which they are substantially
parallel to the flow direction.
[0015] The operation of the damper blades 7 to 1
0 is effected by means of an arm 14 secured to the journal 12 for one of the damper
blades 7, and the damper blades 7 to 10 are interconnected with respect to movability
through a drive mechanism, including a coupling bar 15, a pivot arm 16 positioned
behind the coupling bar 15 being rotatably connected with the coupling bar 15 and
secured to one of the journals for each damper blade.
[0016] According to the invention, to obtain lateral tightness of the damper blades 7 to
10 in the closing position of the damper assembly the opposite sides of the lateral
frame members 1 and 3 facing the flow passage area have a substantially convex cross-sectional
shape as shown in Fig. 3 with the minimum distance between the frame members 1 and
3 aligned with the bearing bushings 13 for the journals 12 of the damper blades 7
to 10, in addition to which the end portion 11 of the damper blade has a curved edge
portion 11 a facing the frame members as best shown in Fig. 4. In the illustrated
embodiment the substantially convex cross-sectional shape is obtained by slightly
bending a plane frame member along parallel bending lines 17 and 18, delimiting a
central striplike portion of a width corresponding to the diameter of the drawn bushings
13.
[0017] In the closing position illustrated in Fig. 4 the curved edge portions 11 a of the
end portions 11 tightly engage the central portion of the frame member 1 opposite
the bearing bushings 13 so as to obtain for most applications a sufficient security
against air passing through between the end of the damper blades 7 to 10 and the frame
members without using any particular tightening means.
[0018] Said lateral tightness is simultaneously obtained without considerably reducing the
movability of the damper blades, inasmuch as each damper blade as soon as it has been
slightly moved away from the closing position as shown in Fig. 3 will get clear of
the frame member on the major part of the length of the end member due to the convex
cross-sectional shape of the frame member. As a consequence of the curved edge portion
11 a of the end portion 11 there are substantially only punctiform engagements between
the end portion 11 and the frame member 1 in the two engagement points positioned
diametrically opposite on either side of the bearing bushing 13. During the movement
of the damper blade between its closing position and its opening position said engagement
points will follow a circular path around the bearing bushing.
[0019] The above mentioned bendings 17 and 18 to obtain the substantially convex cross-sectional
shape of the frame member 1 may for instance be made so that the clearance between
the frame member and the end portion 11 of the damper blade in its opening position
varies from approximately 0 to 1-2 mm.
1. A ventilation damper assembly to be mounted in a cabinet, a ventilation duct or
a wall opening and comprising a number of substantially rectangular damper blades
(7-10) of wing-shaped cross-sectional profile mounted rotatably with parallel axes
of rotation between opposite frame members (1, 3) in a substantially rectangular damper
frame, and wherein said opposite frame members (1, 3) are provided with bearings (13)
for journals (12) secured in the damper blades (7-10), said journals being in engagement
with a drive mechanism by which the damper blades (7-10) can be moved between a closing
position and an opening position, characterized in that the opposite sides of said
frame members (1, 3) facing the flow passage area of the damper have a substantially
convex cross-sectional shape with the minimum distance between the frame members (1,
3) aligned with the bearings (13) of the journals (12) of the damper blades (7-10),
and in that the end portions (11) of each damper blade comprise a curved edge portion
(11 a) facing the frame members (1, 3).
2. A ventilation damper assembly according to claim 1, characterized in that the substantially
convex cross-sectional shape is obtained by providing the frame members (1, 3) with
slight bendings in relation to a plane along parallel bending lines (17, 18) delimiting
a central strip of a width corresponding to the diameter of the bearings (13) for
the journals (12) of the damper blades (710).
1. Lüftungsdrosseleinrichtung zum Einbau in ein Gehäuse, einen Lüftungskanal oder
eine Wandöffnung, umfassend eine Anzahl im wesentlichen rechteckiger Drosselklappen
(7-10) mit flügelförmigem Querschnittsprofil, welche Drosselklappen mit parallelen
Rotationsachsen zwischen einander gegenüberliegenden Rahmenteilen eines im wesentlichen
rechteckigen Drosselrahmens drehbar angeordnet sind, welche einander gegenüberliegenden
Rahmenteile (1, 3) mit Lagern (13) für in den Drosselklappen (7-10) befestigten Drehzapfen
(12) versehen sind, die mit einem Antriebsmechanismus in Eingriff stehen, mittels
welchem die Drosselklappen (7-10) zwischen einer Schliesstellung und einer Öffnungsstellung
bewegt werden können, dadurch gekennzeichnet, dass die einander gegenüberliegenden,
dem Durchströmungsbereich der Drosseleinrichtung zugekehrten Seiten der Rahmenteile
(1, 3) eine im wesentlichen konvexe Querschnittsform aufweisen, wobei die Rahmenteile
(1, 3) ihren Mindestabstand zwischen den Lagern (13) der Drehzapfen (12) der Drosselklappen
(7-10) haben, und dass die Endteile (11) jeder Drosselklappe einen den Rahmenteilen
zugekehrten, abgerundeten Kantenteil (11a) aufweisen.
2. Lüftungsdrosseleinrichtung nach Anspruch 1, dadurch gekennzeichnet, dass die im
wesentlichen konvexe Querschnittsform dadurch erzielt ist, dass die Rahmenteile (1,
3) im Verhältnis zu einer Ebene entlang paralleler Biegungslinie (17, 18) mit leichten
Biegungen versehen sind, die einen Mittelstreifen mit einer dem Durchmesser der Lager
(13) der Drehzapfen (12) der Drosselklappen (7-10) entsprechenden Breite begrenzen.
1. Registre de ventilation pour montage dans un coffret, une gaine d'aération ou une
ouverture d'un mur et comprenant un nombre de clapets (7-10) essentiellement rectangulaires
dont la forme en coupe est celle d'une aile et qui sont montés à rotation, les axes
de rotation étant parallèlles, entre des pièces de cadre opposées (1 et 3) dans un
cadre de registre essentiellement rectangulaire et dans lequel lesdits pièces de cadre
opposées (1 et 3) sont pourvues de paliers (13) pour des tourillons (12) fixés dans
les clapets de registre (7-10), lesdits tourillons étant en prise avec un mécanisme
de commande à l'aide duquel les clapets de registre (7-10) peuvent être manoeuvrés
entre une position de fermeture et une position d'ouverture, caractérisé en ce que
les côtés desdites pièces de cadre (1 et 3) qui sont orientés vers l'orifice de passage
de l'air ont, en coupe, une forme essentiellement convexe avec la plus faible distance
entre les pièces de cadre (1 et 3) alignée avec les paliers (13) des tourillons (12)
des clapets de registre (7-10), et en ce que les extrémités (11) de chaque clapet
de registre comportent une arête arrondie (11a) face aux pièces de cadre (1 et 3).
2. Registre de ventilation selon la revendication 1, caractérisé en ce que la forme
en coupe essentiellement convexe est obtenue en courbant légèrement les pièces de
cadre (1 et 3) par rapport à un plan le long des lignes de courbure parallèlles (17
et 18) délimitant une bande centrale d'une largeur qui correspond au diamètre des
paliers (13) des tourillons (12) des clapets de registre.