Integrated fan assembly with variable pitch blades

A fan assembly adapted to be readily removably attached, as a unit, to a drive device, comprising, in combination:

• a housing including first and second interconnected housing sections, with the first and second housing sections having inner wall portions which are spaced so as to define an internal housing chamber, with at least one of the first and second housing sections including a plurality of circumferentially spaced openings formed in a peripheral portion thereof;
• a plurality of first fasteners interconnecting the first and second housing sections at first, circumferentially spaced locations;
• a plurality of blade units, with each of the blade units including a support stem being mounted in a respective one of the openings;
• and a plurality of second fasteners for removably attaching the housing to the drive unit, with access to the plurality of first fasteners being adapted to be blocked by the drive unit such that disassembly of the first and second housing sections is only permitted upon detaching the housing from the drive unit.

A fan assembly adapted to be rotated by a drive device and adapted to be adjusted during operation to alter the air flow characteristics of the fan assembly, comprising, in combination;

• a housing having a peripheral portion formed with a plurality of circumferentially spaced openings;
• a hub member extending from the housing at a position spaced radially from the openings, with the hub member including a plurality of circumferentially spaced pockets, with each of the pockets being aligned with a respective one of the openings;
• an actuator member shiftably mounted relative to the housing;
• and a plurality of blade units, with each of the blade units including a support stem and a fan blade having a base attached to the support stem, with the support stem of each blade unit including a cylindrical journal portion rotatably mounted in a respective one of the openings and a post portion which extends from the journal portion, along a common longitudinal axis, with the post portion including a terminal end rotatably mounted in a respective one of the pockets such that each blade unit is supported at two, radially spaced locations for rotation relative to the housing to vary a pitch or the fan blades, thereby altering the air flow characteristics of the fan assembly, with the actuator member being interconnected with the support stem of each of the blade units such that movement of the actuator member relative to the housing causes the fan blades to rotate relative to the housing to vary the pitch of the fan blades, with the actuator member being constituted by a piston having a central recess portion into which the hub member including the plurality of circumferentially spaced pockets extends for linearly guiding the piston for movement relative to the housing, with the piston including a plurality of radially extending grooves aligned with the plurality of circumferentially spaced pockets included in the hub member, with the support stems of the blades being received in the radially extending grooves of the piston.

A fan blade unit adapted to be rotatably mounted as an integrated, one-piece assembly within an opening formed in a housing of a fan assembly having air flow characteristics which can be altered during operation by adjusting a pitch of the fan blade unit, comprising, in combination:

• an integrally formed support stem including a cylindrical journal portion adapted to be rotatably mounted within the opening formed in the housing, a post portion extending, along a common longitudinal axis, from the journal portion and including a terminal end spaced, along the longitudinal axis, from the journal portion and an enlarged flange portion interposed between the journal portion and the post portion, with the flange portion being adapted to be sized diametrically larger than both the post portion and the opening within which the journal portion is rotatably mounted, with the terminal end of the post portion having a shape and size adapted to be rotatably supported by the housing at a position spaced from the opening within which the journal portion is rotatably mounted;
• a pin member projecting from the flange portion at a position offset from the post portion and from the common longitudinal axis wherein, when the fan blade unit is mounted for rotation about the journal portion and the post portion, the pin member can be engaged to cause the support stem to rotate about the common longitudinal axis to vary the pitch of the fan blade;
• and a fan blade having a base portion formed about the support stem such that the support stem and the fan blade constitute an integrated assembly adapted to be mounted to the housing as a single unit.

A fan assembly adapted to be removably attached, as a unit, to a drive unit and adapted to be adjusted during operation to alter air flow characteristics of the fan assembly, comprising, in combination:

• a housing drivingly connected to the drive device for rotation about a first axis, with the housing including first and second interconnected housing sections having inner wall portions which are spaced so as to define an internal housing chamber, with the housing including a plurality of circumferentially spaced openings formed in a peripheral portion thereof, with each housing section defining an arcuate portion of each opening;
• a hub member extending from one of the first and second housing sections, within the internal housing chamber, at a position spaced radially from the openings, with the hub member including a plurality of circumferentially spaced pockets, with each of the pockets being aligned with a respective one of the openings;
• a plurality of integrated, one-piece blade units, with each of the blade units including an integrally formed support stem and a fan blade having a base formed about the support stem such that the support stem and the fan blade constitute an integrated assembly adapted to be mounted to the housing as a single unit, with the support stem of each blade unit including a cylindrical journal portion rotatably mounted in a respective one of the openings, a post portion which extends from the journal portion, along a common longitudinal axis, and includes a terminal end rotatably mounted in a respective one of the pockets such that each blade unit is supported at two, radially spaced locations for rotation relative to the housing to vary a pitch of the fan blades, thereby altering the air flow characteristics of the fan assembly, and an enlarged flange portion interposed between the journal portion and the terminal end of the post portion, with the flange portion being diametrically sized larger than both the post portion and the opening within which the journal portion is rotatably mounted;
• an actuator member mounted within the housing for concurrent rotation with the housing about the first axis and axial movement relative to the housing along the first axis through indefinitely variable positions, with the actuator member being connected to each of the blade units such that selective axial movement of the actuator member controls the pitch of the fan blades;
• a plurality of first fasteners interconnecting the first and second housing sections at first, circumferentially spaced locations;
• a plurality of second fasteners for removably attaching the housing to the drive unit, with access to the plurality of first fasteners being adapted to be blocked by the drive unit such that disassembly of the first and second housing sections is only permitted upon detaching the housing from the drive unit;
• and a sensing system including a first sensor element attached to the actuator member so as to both rotate in unison with the actuator member about the first axis and to shift in unison with the actuator member along the first axis and a second sensor element fixed to the drive unit, with the second sensor element being adapted to sense both a rate of rotation of the first sensor element about the first axis and a degree of shifting of the first sensor element in order to develop signals indicative of a rotating speed and axial position of the actuator member which, in turn, correspond to a rotating speed and pitch of the blade units.