U.S. patent application number 10/809784 was filed with the patent office on 2004-12-30 for duct fan.
This patent application is currently assigned to BEHR GmbH & CO.. Invention is credited to Bielesch, Thomas, Rogg, Stefan.
Application Number | 20040265126 10/809784 |
Document ID | / |
Family ID | 32798138 |
Filed Date | 2004-12-30 |
United States Patent
Application |
20040265126 |
Kind Code |
A1 |
Bielesch, Thomas ; et
al. |
December 30, 2004 |
Duct fan
Abstract
The invention relates to a duct fan having a distributor and an
impeller that is drivable by a motor. The distributor has a
plurality of vanes which can be connected to the duct to mount the
tube fan in a duct.
Inventors: |
Bielesch, Thomas;
(Muhlacker, DE) ; Rogg, Stefan; (Stuttgart,
DE) |
Correspondence
Address: |
FOLEY AND LARDNER
SUITE 500
3000 K STREET NW
WASHINGTON
DC
20007
US
|
Assignee: |
BEHR GmbH & CO.
|
Family ID: |
32798138 |
Appl. No.: |
10/809784 |
Filed: |
March 26, 2004 |
Current U.S.
Class: |
415/220 |
Current CPC
Class: |
F04D 25/082 20130101;
F04D 29/542 20130101; F04D 29/668 20130101 |
Class at
Publication: |
415/220 |
International
Class: |
F04D 005/00 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 27, 2003 |
DE |
103 13 991.5 |
Claims
What is claimed is:
1. A duct fan adapted to be arranged in a duct, comprising a motor,
an impeller adapted to be driven by the motor, and a distributor
having a plurality of vanes which are adapted to contact the duct
and form a connection between the duct and the motor.
2. The duct fan as claimed in claim 1, wherein the motor is
arranged within the distributor and comprises an electric
motor.
3. The duct fan as claimed in claim 2, wherein the duct fan
comprises a configuration to be arranged coaxially in the duct.
4. The duct fan as claimed in claim 2, wherein the vanes are
distributed at equidistant spacings from one another around a
circumference of the distributor.
5. The duct fan as claimed in claim 1, wherein at least one vane is
designed as a cooling device.
6. The duct fan as claimed in claim 1, wherein at least one vane
comprises an air-supply or air-discharge duct for separate air
cooling from outside the tube.
7. The duct fan as claimed in claim 6, which further comprises a
cooling impeller for separate air cooling with air drawn through
said air-supply duct, the cooling impeller being driven by the
motor.
8. The duct fan as claimed in claim 2, wherein the power supply for
the electric motor is provided through at least one of the
vanes.
9. The duct fan as claimed in claim 8, wherein at least one of the
vanes has one or more through-openings or longitudinal grooves
designed as a cable duct.
10. The duct fan as claimed in claim 8, wherein at least one
externally insulated, electrically conductive element forms the
core of at least one vane forming the power supply for the electric
motor.
11. The duct fan as claimed in claim 10, wherein the electrically
conductive element comprises a bent sheet-metal part.
12. The duct fan as claimed in claim 8, further comprising an
electrical contact-connection at the radially outer end of one
vane.
13. The duct fan as claimed in claim 8, which further comprises at
least one control element and respective spatially separate infeeds
for the power supply of the electric motor and the power supply for
the at least one control element.
14. The duct fan as claimed in claim 13, wherein the at least one
control element is electronic and is arranged in the
distributor.
15. The duct fan as claimed in claim 2, wherein the distributor
forms a housing of the motor.
16. The duct fan as claimed in claim 1, wherein at least two vanes
comprise attachment points at their outer ends.
17. The duct fan as claimed in claim 16, wherein the attachment
points comprise bores with internal threads.
18. The duct fan as claimed in claim 16, further comprising an
electrical connector as an additional attachment point for the
distributor.
19. The duct fan as claimed in claim 16, wherein the attachment
points for the distributor to the duct further comprise a
noise-isolating element.
20. The duct fan as claimed in claim 19, wherein the
noise-isolating elements are comprised of an elastomeric material.
Description
CROSS-REFERENCE TO RELATED PATENT APPLICATIONS
[0001] Federal Republic of Germany Priority Application 103 13
991.5, filed Mar. 27, 2003 including the specification, drawings,
claims and abstract, is incorporated herein by reference in its
entirety.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to a duct fan having a
distributor that has a plurality of vanes.
[0003] DE 26 07 984 A1 discloses a duct fan having an axial
impeller that is driven coaxially in the duct that is to be
ventilated, by a low-power electric motor arranged within the
cylindrical or frustoconical impeller hub. Radial supporting
crosspieces are provided, and these serve as the fastening
framework of which the external diameter is spaced apart only
slightly from the inner wall of the duct for a snug fit. In this
case, the fastening framework is designed as a single-piece plastic
injection molding. Such a duct fan, however, still leaves something
to be desired.
SUMMARY OF THE INVENTION
[0004] One object of the invention is to provide an improved duct
fan.
[0005] In accomplishing the objects of the invention, there has
been provided according to one aspect of the invention a duct fan
adapted to be arranged in a duct, comprising a motor, an impeller
adapted to be driven by the motor, and a distributor having a
plurality of vanes which are adapted to contact the duct and form a
connection between the duct and the motor.
[0006] Further objects, features and advantages of the present
invention will become apparent from the detailed description of
preferred embodiments that follows, when considered together with
the accompanying figures of drawing.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] In the drawings:
[0008] FIG. 1 is a cut-away view of a first exemplary
embodiment,
[0009] FIG. 2 is a view, in detail form, of the electrical
contact-connector,
[0010] FIG. 3 is a cross-sectional view taken transversely to the
longitudinal axis in order to illustrate the cable guidance,
[0011] FIG. 4 is a cross-sectional view taken transversely to the
longitudinal axis for a second exemplary embodiment, and
[0012] FIG. 5 is a side view of a distributor with integrated
drive.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0013] According to the invention the fastening function is
integrated into the vanes of a distributor. The invention provides
a duct fan having a distributor that has a plurality of vanes. The
vanes of the distributor are connected to the duct at the outer
end. This means that there is no need for any additional struts,
for fastening and stabilizing purposes, which would adversely
affect the air flow.
[0014] It is preferable for the vanes to be distributed around the
circumference of a base body of the distributor; however not all
the vanes necessarily serve for fastening purposes. It is possible
for the vanes to be arranged at equidistant spacings from one
another or to be distributed in some other way around the
circumference. It is also possible, in particular, for the vanes to
be configured with different thicknesses in order to accommodate,
for example, an air supply for separate air cooling.
[0015] The distributor may be fixed, for example, to a housing of
the motor, in which case a shaft of the motor is then
advantageously fixed to the impeller. Conversely, it is also
conceivable for the impeller to be fastened on the motor housing,
in which case a motor shaft is then preferably fastened on the
distributor.
[0016] According to a preferred embodiment, the bases of the vanes
are connected to the base body of the distributor. The base body of
the distributor serves as a mount (motor holder) for an electric
drive, for example, for a brush motor. In a preferred construction,
the entire distributor (base body+vanes) is designed as a complete
drive (as a unit), it being possible to integrate all common types
of motors (brush motor, brushless motor, reluctance motor, etc).
The basic body of the distributor thus forms the cylindrical base
body of the electric motor. The duct fan is then designed as an
entire system, which vastly simplifies final assembly.
[0017] It is preferable for at least one vane to be designed as a
cooling device. Provision is made in this regard for thermal
contact connection between the vane, if appropriate, the base body
of the distributor, and the electric motor, thereby resulting in
good thermal conduction from the electric motor to the outside. It
is also possible for electronic components which are arranged, for
example, in the interior of the base body to be cooled in this way.
If all the vanes are of corresponding design, this still gives
rise, on account of the relatively large surface area of the vanes,
to a sufficiently good cooling effect at high air temperatures,
despite a relatively small temperature difference. For this
purpose, the vanes and/or the base body are/is produced,
particularly wholly or partially, from metal, preferably
aluminum.
[0018] One preferred embodiment provides separate air cooling from
the outside. Air-supply, and possibly also air-discharge, ducts are
arranged in one or more vanes in this embodiment. An impeller for
the separate air cooling is preferably arranged in the interior of
the distributor, this impeller being connected, for example,
directly to the output shaft of the electric motor, on which the
impeller is likewise preferably fitted. In this case, it is
possible, despite the high temperatures, for individual
air-channeling vanes, or all of these vanes, to be produced from
plastic. In another preferred embodiment, the air from the separate
air-cooling means flows out into the duct without an impeller.
[0019] The power supply of the electric motor is preferably
provided through at least one of the vanes. It is possible, for
this purpose, for one or more vanes to be provided with one or more
cable ducts and/or through-openings through which cables are
guided. It is particularly preferred for the normal power supply of
the electric motor and for the control current (for electronics) to
be spatially separated, thus reducing the susceptibility to
malfunctioning. Avoiding the hitherto free feeding of cables
improves the channeling of air, since there are no aerodynamic
resistances present, and the noise level is thus also reduced.
[0020] According to an alternative embodiment, instead of a cable,
the power-conduction means is formed by one or more externally
insulated, electrically conductive elements which form the core of
at least one vane. These elements are preferably bent sheet-metal
parts.
[0021] An electrical contact-connection means is preferably
provided at the radially outer end of the vane. This may be, in
particular, a plug socket, but also a plug, as a result of which
straightforward and quick contact and connection is possible
following installation.
[0022] The power and control electronics are preferably arranged in
the inner region of the distributor, in particular at locations
which are particularly well cooled.
[0023] It is preferable for at least two vanes, in particular
widely spaced-apart vanes, to be provided, at their outer end, with
mounts and/or internal threads. Pins, screws or other fastening
means are introduced into the latter for the purpose of fastening
the duct fan, these fastening means ensuring a secure connection
between the duct and impeller. This simplifies assembly and thus
reduces the production costs. In a preferred construction, it is
also possible to arrange isolating elements, for noise-reduction
purposes, between the vanes and the duct.
[0024] For this purpose, it is preferable to provide, on three
approximately equally spaced-apart vanes, bores with internal
threads, which are aligned with bores in the duct and into which
screws are inserted. As an alternative, it is possible for just two
vanes to be fixed to the duct by means of various fastening
elements, and a housing of an integrated plug being configured such
that the latter, in addition, forms the third fastening point.
Fixing at the third fastening point is preferably configured such
that assembly can be realized with very low outlay, such as, in a
preferred configuration, by a plug-in connection with a close
fit.
[0025] Connection of the vanes of the duct fan to the duct is
simplified, according to one advantageous configuration, in that
the duct has a shoulder which serves as a stop for the vanes. In
another embodiment, the vanes may be connected by an outer ring, in
which case the outer ring is then connected to the duct. In a
further embodiment, the vanes may have, at their ends, thickened
portions which can be plugged, for example, into grooves in the
duct.
[0026] In all the types of connection described, it is possible for
isolating elements, e.g., made of elastomeric material, to be
positioned between the duct fan and duct.
[0027] Turning now to the drawings, a duct fan 2 according to the
invention, which is arranged coaxially in a duct 1, comprises an
impeller 3 with its impeller hub 4, an electric motor 5, in the
exemplary embodiment a brush motor, and a distributor 6 with vanes
7. The impeller 3 is driven by the electric motor 5, which is
arranged in the distributor 6. In addition to performing the
function of directing air, the vanes 7, also simultaneously serve
as supporting struts and for fastening on the duct 1. For the
latter purpose, according to the present exemplary embodiment, two
screws project from the outside through corresponding bores in the
duct 1 and are screwed into threaded bores provided in two of the
vanes 7. The third fastening point is formed by the connector plug
housing 9. Further additional functions of the vanes 7 will be
described later in the text.
[0028] Provided for supplying the electric motor with power is a
cable 8, which extends from the electric motor 5 and is guided
outwardly through one of the vanes 7 that forms a cable duct, i.e.
the electrical supply lead is integrated. The cable 8 terminates in
a plug housing 9, which can be contact-connected from outside the
duct 1 (see FIGS. 2 and 3).
[0029] The duct fan 2 is operated at high air temperatures, for
example of 125.degree. C., as a result of which conventional duct
fans are beset by cooling problems in relation to the electric
motor 5. According to the first exemplary embodiment, heat is
discharged from the electric motor 5, which is arranged in the
impeller hub 4, via the base body of the distributor 6, to the
vanes 7. The vanes are designed as a cooling device, have a
comparatively large surface area and are exposed to the air flowing
past, which in the present embodiment flows first past the impeller
3 and then past the vanes 7, with the result that optimum discharge
of heat can take place. For this reason, even a relatively small
temperature difference between the air temperature and
electric-motor temperature is sufficient for cooling the electric
motor 5. By virtue of heat being discharged outwardly, it is also
the case that other components, for example transistors, which are
part of power and/or control electronics 10 are protected against
overheating.
[0030] A second exemplary embodiment essentially corresponds to the
first exemplary embodiment, and in this case the same or equivalent
elements are provided with designations that are higher by 100 than
in the first exemplary embodiment. In the second exemplary
embodiment, the cooling device, which is formed by the vanes 107,
is accompanied by a second cooling device, which supplies cooler
air to the electric motor 105 from outside the duct. For this
purpose, two vanes 107 are provided with air ducts 120, of which
one serves for supplying air and one serves for discharging air.
The airflow is indicated schematically by arrows in FIG. 4.
Provided in the interior of the distributor 106 is a cooling
impeller 121 which is driven by the same electric motor 105 as
drives the previously described impeller. The cooler air supplied
from the outside cools not just the electric motor 105, but also
the power and control electronics thereof.
[0031] Corresponding to the first exemplary embodiment, the power
supply of the electric motor 105 is preferably provided via a cable
(not illustrated) which is guided through one of the vanes 107. The
control current is typically supplied separately, via a further,
correspondingly designed arrangement.
[0032] One of the three fastening devices 114 (e.g., threaded bore)
is indicated schematically on the central vane 107 in FIG. 5, as
well as a resilient isolating element 112.
[0033] The foregoing description of preferred embodiments of the
invention has been presented for purposes of illustration and
description. It is not intended to be exhaustive or to limit the
invention to the precise form disclosed, and modifications and
variations are possible and/or would be apparent in light of the
above teachings or may be acquired from practice of the invention.
The embodiments were chosen and described in order to explain the
principles of the invention and its practical application to enable
one skilled in the art to utilize the invention in various
embodiments and with various modifications as are suited to the
particular use contemplated. It is intended that the scope of the
invention be defined the claims appended hereto and that the claims
encompass the disclosed embodiments and their equivalents.
* * * * *