Fan blade retention system and related methods
A fan includes a motor adapted to be rotated about an axis and a hub adapted to be rotated by the motor. The hub may include first and second hub parts adapted to mate to form the hub, the first and second hub parts having a gap therebetween. A plurality of fan blades each includes an end portion located in the gap formed between the first and second hub parts, which may be drawn together by a fastener to capture the blades therebetween. One or more of the fan blades may include a receiver, such as an open-ended groove, for receiving a portion of the hub. An adapter may be configured to remain stationary during use while the hub and fan blades rotate, and a portion of the hub is adapted to be selectively deployed to engage the adapter to prevent rotation of the hub. Related methods are also disclosed.
1 . A fan, comprising:
a motor;
a hub adapted to be rotated about an axis by the motor, the hub comprising first and second hub parts, each of the first and second hub parts being annular in shape and defining a central aperture, the first and second hub parts being adapted to mate to form the hub, and the first and second hub parts having a gap therebetween; and
a plurality of fan blades, each of the fan blades having an end portion located in the gap formed between the first and second hub parts;
wherein the end portion of each of the plurality of blades includes a blade receiver, the first hub part includes at least one alignment projection, and the second hub part includes at least one alignment receiver, and wherein the blade receiver and the alignment receiver are both adapted to receive the alignment projection when the first and second hub parts mate to form the hub.
2 . The fan of claim 1 , wherein the first and second hub parts each includes axially aligned apertures and further including at least one fastener for positioning in the axially aligned apertures to connect the first and second hub parts.
3 . The fan of claim 2 , further including a hub cover adapted to cover at least one of the first and second hub parts, the hub cover including a generally circumferentially extending slot for receiving the end portion of at least one fan blade.
4 . The fan of claim 3 , wherein the hub cover includes at least one access opening for aligning with the axially aligned apertures of the first and second hub parts to provide access to the fastener.
5 . The fan of claim 4 , further including an adapter configured to remain stationary during use while the hub and plurality of fan blades rotate, and wherein the first hub part includes a projection adapted to engage the adapter to prevent rotation of the hub when the fastener is loosened while still retaining the first hub part to the second hub part, and to allow rotation when the fastener is sufficiently tightened to secure the plurality of fan blades in place.
6 . The fan of claim 1 , wherein the blade receiver comprises an open-ended groove for receiving the alignment projection, and wherein the alignment projection is an axially extending projection.
7 . The fan of claim 1 , wherein the first and second hub parts each include opposing contoured or curved surfaces that match corresponding surfaces of the end portions of the plurality of blades.
8 . The fan of claim 1 , wherein the first hub part includes a first surface facing the second hub part, and the second hub part includes a second surface facing the first hub part;
wherein the first surface includes a first projection and a first receiver, and wherein the second surface includes a second projection and a second receiver;
wherein the first projection mates with the second receiver and wherein the second projection mates with the first receiver.
9 . The fan of claim 1 , where the first hub part includes a projection that mates with both a recess in the second hub part and further mates with a groove in at least one of the plurality of fan blades.
10 . A fan, comprising:
a motor;
a hub adapted to be rotated about an axis by the motor, the hub comprising first and second hub parts adapted to mate, each of the first and second hub parts being annular in shape and defining a central aperture, the first hub part including an alignment projection generally aligned with the axis, and the second hub part including an alignment receiver adapted to mate with the alignment projection to limit relative movement between the first and second hub parts; and
a plurality of fan blades, at least one of the plurality of fan blades having an end portion with a blade receiver adapted to receive the alignment projection.
11 . The fan of claim 10 , wherein the blade receiver comprises an open-ended groove extending transversely to the axis, the open-ended groove having a first width substantially equal to a second width of the alignment projection.
12 . The fan of claim 10 , wherein the alignment projection and the alignment receiver each comprises an aperture adapted to receive a fastener adapted to fasten the first and second hub parts together.
13 . The fan of claim 10 , wherein the second hub part includes a plurality of second projections, the plurality of fan blades each include a plurality of second blade receivers, and the first hub part includes a plurality of second receivers; and
wherein each of the second blade receivers and the second receivers of the first hub part are adapted to receive at least one of the second projections of the second hub part.
14 . The fan of claim 10 , wherein the first and second hub parts include contoured or curved surfaces that match a corresponding surface of at least one of the one or more fan blades.
15 . The fan of claim 10 , further including an adapter configured to remain stationary during use while the hub and fan blades rotate, and wherein the first hub part includes a projection adapted to engage the adapter to prevent rotation of the second hub when separated apart but still connected and to allow rotation when the first and second hub parts are in position for securing the one or more blades in place.
16 . A fan, comprising:
a motor;
a hub adapted to be rotated about an axis by the motor, the hub comprising first and second hub parts, each of the first and second hub parts being annular in shape and defining a central aperture;
a plurality of fan blades adapted to be connected to the hub; and
an adapter configured to remain stationary during use while the hub and fan blades rotate, wherein one of the first and second hub parts is adapted to be selectively deployed to engage the adapter to prevent rotation of the hub;
wherein each of the fan blades includes an end portion located in a gap formed between the first and second hub parts, each end portion includes a blade receiver, the first hub part includes at least one alignment projection, and the second hub part includes at least one alignment receiver; and
wherein the blade receiver and the alignment receiver are both adapted to receive the alignment projection when the first and second hub part are mated to form the hub, so as to limit movement of the blade with respect to the hub.
17 . The fan of claim 16 , further including at least one fastener adapted for connecting the first and second hub parts together, wherein a loosened condition of the fastener corresponding to a position of the portion of the hub to prevent rotation thereof.
18 . A method of assembling a fan, comprising:
providing first and second annular parts of a hub, each defining a central aperture, the first and second annular parts of the hub adapted to be rotated by a motor, the first part of the hub including at least one alignment projection and the second part of the hub including at least one alignment receiver;
providing a plurality of fan blades, each of the plurality of fan blades including an end portion with a blade receiver; and
capturing the end portion of each of the plurality of fan blades between the first and second annular parts of a hub such that the blade receiver of at least one of the plurality of fan blades and the at least one alignment receiver both receive the at least one alignment projection so as to limit relative movement between the first and second annular parts of the hub and the at least one of the plurality of fan blades.
19 . The method of claim 18 , wherein the capturing step comprises passing an end portion of at least one fan blade through a slot in a hub cover and into a gap between the first and second annular parts, and then tightening one or more fasteners to close the gap and capture the end portion between the first and second annular parts.
20 . The method of claim 19 , wherein the blade receiver of each fan blade includes a groove, and the passing step comprises passing the alignment projection into the groove.
21 . The method of claim 18 , further including the step of preventing rotation of the hub when the first and second annular parts are separated to install or remove one or more of the plurality of fan blades.