Fluid reaction surfaces (i.e. – impellers) – Specific working member mount – Distally supported on radial arm
Reexamination Certificate
2000-01-24
2002-05-07
Ryznic, John E. (Department: 3745)
Fluid reaction surfaces (i.e., impellers)
Specific working member mount
Distally supported on radial arm
Reexamination Certificate
active
06382917
ABSTRACT:
BACKGROUND
1.0 Field of the Invention
The present invention relates generally to ceiling fans and, more particularly, to ceiling fans having the blade irons which support the fan blades mounted to a rotatable fan housing.
2.0 Related Art
Ceiling fans include a plurality of fan blades which are rotated by an electric motor to provide a supplementary means of conditioning air within both commercial and residential buildings. Ceiling fans typically include a stationary fan housing, which may include an ornamental exterior design and may assume a wide variety of shapes, disposed in surrounding relationship with the electric motor. Fan housings are sometimes referred to in the art as motor housings. However, it is understood in the art that the primary purpose of fan housings is to obscure the electric motor from view to provide a more aesthetically pleasing appearance to the ceiling fan and it is further understood that the fan housing is not part of the electric motor but instead is a separate component of the ceiling fan. The stationary fan housing is supported by the stationary structure used to suspend the ceiling fan. For instance, with ceiling fans utilizing a downrod and ball arrangement in conjunction with a ceiling mounted canopy to suspend the fan, the stationary fan housing may be attached to an adaptor which is secured to the lower end of the downrod.
The electric motors used in ceiling fans comprise either “standard configuration” or “inside-out” electric motors. With “standard configuration” motors the rotor, which comprises a rotating portion of the motor, is disposed radially inwardly of the stator or stationary portion of the motor which includes the electric windings of the motor. The opposite configuration exists in “inside-out” motors, i.e., the rotor is disposed radially outwardly of the stator. Regardless of the type of electric motor used, it may be appreciated that the fan blades must be connected to and rotatably driven by a rotating portion of the motor to provide the desired rotation of the blades. The rotating portion of an “inside-out” electric motor may include upper and lower end caps or end bells in addition to the rotor.
Various means may be used to mount the fan blades to the rotating portion of an “inside-out” electric motor of a ceiling fan, with one commonly employed mounting arrangement being disclosed in U.S. Pat. No. 5,462,412. As best seen in
FIG. 2
, each fan blade
20
is fastened to a distal end
66
of a blade iron
62
, with the proximal end
64
of each blade iron
62
being fastened to a lower surface
72
of motor
16
via screw
70
.
Another commonly employed ceiling fan blade mounting arrangement is disclosed in U.S. Pat. No. 5,222,864. As shown in
FIGS. 2 and 3
, the radially inner end of each fan blade
20
is mounted to a wedge shaped member
84
disposed on an upper surface
22
of motor
16
via screws
88
. It is noted that the fan housings disclosed in each of the foregoing patents (denoted by reference no.
18
in both patents) comprise stationary housings.
U.S. Pat. No. 5,944,487 discloses yet another ceiling fan blade attachment system. As shown in
FIG. 1
, the disclosed system includes a blade mounting ring
21
which is disposed below and fixedly attached to a motor mounting face
5
of a rotatable, lower motor casing portion
13
of inside-out motor
1
via bolts
17
. The blade mounting ring
21
includes a plurality of fan blade mounting brackets
31
which extend outwardly from a substantially cylindrical portion
29
of ring
21
. Each of the disclosed fan blades
35
is affixed to the underside of one of the brackets
31
with screws or bolts.
U.S. Design Pat. No. D.361,377 discloses two embodiments of a ceiling fan and light fixture which include a fan housing having stationary upper and lower portions and a rotatable center portion disposed therebetween, with each fan blade passing through slots formed in the center portion of the fan housing at a location near the inner end of the blade. Although not shown in the design patent, it is known in the art that the rotatable center portion of the fan housing is mounted to a rotatable lower portion of the included electric motor. As further known in the art, the radially inner end of each fan blade is attached to a radially outer portion of a blade iron which is attached, at a radially inner end thereof, to the rotatable lower portion of the electric motor.
Known ceiling fans also include those having a rotatable fan housing with a lower portion of the fan housing secured to the lower, rotatable end cap of the electric motor, with these fans further including blade irons attached to a bottom, downwardly facing surface of the lower portion of the fan housing.
With regard to “standard configuration” electric motors, the fan blades may be attached to blade irons which are in turn are attached to a rotating flywheel which is secured to a rotor shaft of the electric motor.
Although each of the foregoing fan blade mounting arrangements have enjoyed widespread use, ceiling fan designers continue to search for alternative fan blade mounting arrangements which provide a different “look” to the ceiling fan and which may provide various advantages associated with the manufacture, shipment, assembly and operation of the ceiling fan.
SUMMARY
In view of the foregoing needs, the present invention is directed to a ceiling fan having a different look which is aesthetically pleasing, and several functional advantages, due to the incorporation of side mounted blade irons. More particularly, the ceiling fan of the present invention includes blade irons which are mounted to a radially outwardly facing surface of a rotatable fan housing, with each fan blade being attached to one of the blade irons. In a preferred embodiment, this surface is an outer surface of a substantially cylindrical sidewall of the housing. Since the blade irons are mounted directly to a side surface of the rotatable motor housing, the blade irons may be smaller than those often used with conventional ceiling fans which are mounted to a bottom portion of the motor and are “looped” to obtain the desired vertical position of the blade iron. Accordingly, the blade irons incorporated by the ceiling fans of the present invention may be cheaper, lighter and have a longer service life due to reduced chance of fatigue, as compared to blade irons typically used with conventional ceiling fans. Further, the mounting position of the blade irons will result in less imbalance and therefore reduced “wobble” during operation of the ceiling fan due to a reduction in manufacturing variations in radial location of the bolt holes used to attach the fan blades to the blade irons. The expected reduction in operational ceiling fan wobble is also due to a variety of additional factors including the following. In the first instance, it is believed that the geometry of the blade irons, which extend radially outwardly from the base attached to the substantially cylindrical sidewall of the rotatable housing, will permit less variation in blade center of gravity and blade pitch angle as compared to ceiling fans incorporating blade irons having more complex geometries, such as the aforementioned “loop” due to attachment to the bottom portion of the motor. As known in the art, variations in blade pitch angle contribute to ceiling fan wobble. Furthermore, the simplified geometry of the blade irons results in substantially radially directed forces, as compared to the complex force vector of conventional blade irons having more complex geometry, which enhances the chance for improved fan balancing and therefore reduces operational wobble. Yet another advantage associated with the ceiling fan of the present invention is associated with the shipment of the fan from the manufacturer's facility. The attachment of the rotatable motor housing to the rotor, via multiple circumferentially spaced fasteners, provides a more rigid structure than that associated with many conventional ceiling fans employing a stationary motor housing attached to a centr
Baker, Donelson Bearman & Caldwell
Hunter Fan Company
Ryznic John E.
LandOfFree
Ceiling fan having side mounted blade irons does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Ceiling fan having side mounted blade irons, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Ceiling fan having side mounted blade irons will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2875127