[0001] The external rotor engine fan of the present invention essentially comprises a propeller
or wheel which is formed by a core or rotor-hub provided with a series of blades and
a pin mounted integral with said rotor-hub. The blades are formed by independent elements
which are individually assembled in the rotor-hub and distributed radially therein.
The individual connecting of the blades in the rotor-hub allows the angular adjustment
thereof so as to perform a precise adjustment of the fan according to the installation
requirements, which allows performing this adjustment even in installations that are
already in use. This angular adjustment can be done without having to remove the propeller
from the pin.
[0002] The blades of the fan of the present invention are arranged in the rotor-hub such
that they cannot accidentally come off the latter, being fixed to it in a secure and,
at the same time, adjustable manner, as will be explained below.
[0003] According to the invention, an external rotor engine fan is particularly provided,
incorporating a central rotor-hub, i.e. an engine rotor which works like a hub. This
rotor-hub includes a body mounted integral with the former, such body being able to
be connected to a closure element formed by a matching body. The body mounted integral
on the rotor-hub and the matching body both have semicircular openings or entries
defining corresponding openings for connecting a plurality of blades.
[0004] The blades of the fan of the present invention have a blade zone and an opposite
connecting zone. This connecting zone has a substantially cylindrical, low height
shape to be inserted in each opening formed on the rotor-hub, and a peripheral groove
which fits into a circumferential rim formed in each semicircular opening of the bodies.
This structural design advantageously allows each blade to be removably connected
on the rotor-hub with angular adjustability without the ability of coming off the
rotor-hub once it is mounted thereon.
[0005] To that end, the body mounted integral on the rotor-hub and the matching body have
longitudinal orifices located between every two adjacent openings wherein there are
housed screws which fix the bodies and immobilize the connecting zone of each blade
between them.
[0006] A highly versatile external rotor engine fan is thus obtained given that the variation
of the tilt of the blades becomes a very simple and quick operation. The blades are
further retained in the rotor in a considerably secure manner without there being
any risk that the blades will come off it. Another advantage of the invention is that
it is possible to mount in the same wheel blades having very different characteristics
such that fans with different features can be obtained with a universal rotor design
so it can be adapted to different requirements at a reduced cost.
[0007] The features and advantages of the external rotor engine fan object of the present
invention shall become clearer based on the following description. Said description
corresponds to a preferred embodiment of the invention which will be described hereinafter
as a non-limiting example in reference to the attached drawings in which:
Figure 1 shows an exploded perspective view of an embodiment of an external rotor
engine fan according to the invention in which the blades are shown separated from
the rotor; and
Figure 2 shows an exploded perspective view of the external rotor engine fan of the
Figure 1 in which the blades are shown mounted on the engine rotor.
[0008] The external rotor engine fan described by way of example in relation to the drawings
comprises a central rotor-hub or core (1), i.e. an engine rotor functioning as a hub.
A pin mounted integral on said rotor, rotating with it, and a closure element (2),
are arranged. Arranged between the rotor-hub (1) and the closure element (2) there
is a plurality of blades (3) identical to one another. The blades (3) are independent
elements that are removably connected to the rotor-hub (1) with angular adjustability,
as will be described below.
[0009] The rotor-hub (1) of the fan can be made of plastic, aluminum or any other suitable
material and comprises a body (4) mounted integral thereon. The closure element (2)
of the fan can also be made of plastic, aluminum or any other suitable material and
comprises a matching body (5) that can be connected on the body (4) mounted integral
on the rotor-hub (1) such that the blades (3) are trapped between them and immobilized
once the connection is done.
[0010] The body (4) mounted integral on the rotor-hub (1) has a low, substantially cylindrical
shape and a wide perimetral rim (4a). A series of semicircular openings (6) identical
to one another is formed on said perimetral rim (4a). These semicircular openings
(6) are evenly distributed in said perimetral rim (4a). Each semicircular opening
(6) has a circumferential rim (7).
[0011] The matching body (5) of the closure element (2) also has a low, substantially cylindrical
shape and has a wide perimetral rim (5a). A series of semicircular openings (6) identical
to one another is formed in said perimetral rim (5a). These semicircular openings
(6) are evenly distributed en said perimetral rim (5a). Each semicircular opening
(6) has a circumferential rim (7).
[0012] The semicircular openings (6) define circular openings when both bodies (4, 5) are
connected to one another to form the rotor-hub assembly (1, 2) inside of which the
electric motor (M) of the fan is arranged.
[0013] There are several orifices (8) parallel to the pin mounted integral on the rotor
on the perimetral rim (4a) of the body (4). Said orifices (8) also extend to the matching
body (5) and are located between every two adjacent openings (6). Screws (9) are housed
in said orifices (8) for fixing both bodies (4, 5).
[0014] The blades (3) of the fan comprise a blade zone (10) and an opposite connecting zone
(11). The connecting zone (11) of each blade (3) has a low, substantially cylindrical
shape which is suitably sized to be inserted in each opening defined by the semicircular
openings (6) of each body (4, 5), as previously indicated. The connecting zone (11)
of the blade (3) has a peripheral groove (12) which fits into the circumferential
rim (7) formed in each semicircular opening (6) of the bodies (4, 5).
[0015] For connecting the blades (3) in the rotor of the fan which is shown, the connecting
zone (11) of each blade (3) is inserted in the openings of the rotor-hub (1) formed
when the bodies (4, 5) forming it are interlocked. When the connecting zone (11) of
the blade (3) is inserted in the openings of the rotor-hub (1), the circumferential
rim (7) of the openings fits into the peripheral groove (12) of the connecting zone
(11) of each blade (3) when the bodies (4, 5) are connected to one another. Once this
connection is done, the angular position of the blades (3), i.e. the tilt thereof,
is adjusted until achieving the desired orientation according to the operating needs.
Once this tilt of the blades (3) is obtained, the latter are retained in the rotor-hub
(1) and immobilized by tightening the locking screws (9).
[0016] The possibility of arranging projections, ribs or striations to favor retaining the
blades (3) in place in relation to the rotor-hub (1) must also be mentioned. The possibility
of arranging complementary indications such as a graduated scale and a signaling element
for informing the operator of the tilt of the blades (3) in the operation of the assembly
is also provided.
[0017] Having sufficiently described the external rotor engine of the present invention
in correspondence with the attached drawings, it must be understood that any modification
of detail that is considered appropriate can be introduced in such invention provided
that the essential features of the invention comprised in the following claims are
not altered.
1. An external rotor engine fan comprising a central rotor-hub (1), said rotor working
as a hub, and including a body (4) and a closure element (2) formed by a matching
body (5) and a longitudinal pin mounted integral on the central rotor-hub (1), the
bodies (4, 5) having semicircular openings (6) defining corresponding openings for
connecting a plurality of blades (3), characterized in that the mentioned body (4) is mounted integral on said central rotor-hub (1) and in that said body (5) can be connected to the body (4), the mentioned blades (3) comprising
a blade zone (10) and an opposite connecting zone (11), said connecting zone (11)
having a low, substantially cylindrical shape to be inserted in each opening, and
the connecting zone (11) of the blade (3) having a peripheral groove (12) which fits
into a circumferential rim (7) formed in each semicircular opening (6) of the bodies
(4, 5), each blade being removably connected in the assembly-closure element (1, 2)
with angular adjustability.
2. An external rotor engine fan according to claim 1, characterized in that the bodies (4, 5) have longitudinal orifices (8) located between every two adjacent
openings (6) wherein screws (9) are housed for fixing said bodies (4, 5) and immobilizing
the connecting zone (11) of each blade (3) between them.