Back to results
US 11,353,237 B2Granted
Exhaust fan assembly having a system for automatically opening a damper in the event of a power failure
AssigneeCaptive-Aire Systems, Inc.
InventorJoshua J. Hess
Life of this patent
Estimating the term…
Abstract
An exhaust fan configured to exhaust air from a building includes a housing, a fan, and a motor for driving the fan. Overlying the fan is one or more dampers that are moveable from a closed position to an open position. Underlying the dampers is at least one pivot arm per damper that is pivotally connected to the fan and which normally assumes a horizontal position spaced from the overlying damper. A mechanical fusible link is connected to the pivot arm and is configured to break in response to a buildup of heat in and around the dampers. Once the fusible link breaks, then the pivot arm is operative to engage and open the overlying damper.
Claims18
A rooftop exhaust fan for exhausting air from a building comprising:
- a fan assembly including a housing, a motor disposed in the housing, and a fan driven by the motor and configured to induce air to move from the building through the fan assembly;
- one or more dampers moveably mounted to the fan assembly above the motor and fan and configured to move from a generally horizontal closed position to an open position where in the open position exhaust air moves upwardly through the fan assembly;
- a damper actuator assembly configured to open the one or more dampers in response to an electricity failure or a motor failure, the damper actuator assembly comprising:
- i. at least one pivot arm disposed underneath the one or more dampers and configured to move from a generally horizontal position to a raised position where the at least one pivot arm engages the one or more dampers and moves the one or more dampers to the open position;
- ii. a mechanical fusible link connected to the at least one pivot arm and configured to normally hold the at least one pivot arm in the generally horizontal position;
- iii. a gas spring piston extending from the fan assembly to the at least one pivot arm, the gas spring piston being biased to move from a retracted position to an extended position;
- wherein the mechanical fusible link is heat sensitive and configured to break in response to being exposed to a threshold temperature;
- in response to the mechanical fusible link breaking, the gas spring piston is configured to move from the retracted position to the extended position and to move the at least one pivot arm which in turn engages the one or more dampers and raises the one or more dampers to the open position such that exhaust air be exhausted upwardly past the one or more dampers;
- and
- whereby in response to the mechanical fusible link breaking, the at least one pivot arm raises and engages the one or more dampers and moves the one or more dampers to the open position.
7 more elements
An exhausts fan for exhausting air from a building, comprising:
- a fan assembly including a housing, a fan and a motor operatively connected to the fan for driving the same;
- a pair of dampers disposed over the fan and motor, each damper pivotally mounted about a transverse axis and moveable from a generally horizontal closed position to an open position where exhaust air passes through the open damper;
- at least one pivot arm mounted underneath each damper;
- the at least one pivot arm having an inner end portion pivotally mounted to the fan assembly and an outer end portion, and wherein the at least one pivot arm is configured to move from a generally horizontal position to a raised position where the at least one pivot arm engages the overlying damper and moves the damper to the open position;
- a mechanical fusible link connected between the at least one pivot arm and the fan assembly and configured to normally maintain the at least one pivot arm in the general horizontal position;
- an actuator operatively connected between the fan assembly and the at least one pivot arm and configured to bias the at least one pivot arm upwardly towards the raised position, the actuator moveable from a retracted position to an extended position where the actuator causes the at least one pivot arm to move from the generally horizontal position to the raised position;
- and
- the mechanical fusible link normally holding the at least one pivot arm in the general horizontal position against the bias of the actuator, but wherein the mechanical fusible link is configured to break in response to exposure to a threshold temperature;
- wherein when the mechanical fusible link breaks, the actuator moves the at least one pivot arm from the general horizontal position to the raised position where the at least one pivot arm engages and raises the respective overlying damper.
6 more elements
A method of automatically opening a damper of a rooftop exhaust fan in the event of an electricity failure wherein the exhaust fan comprises a housing, a fan mounted in the housing, a motor for driving the fan, and the damper disposed over the motor and fan and moveable from a closed position to an open position, the method comprising:
- positioning at least one pivot arm generally horizontally underneath the damper where the at least one pivot arm is spaced from the damper and does not engage the damper, and wherein the at least one pivot arm is pivotally connected in the exhaust fan and moveable from a generally horizontal position to a raised position;
- holding the at least one pivot arm in the generally horizontal position by connecting a heat sensitive mechanical fusible link between the at least one pivot arm and an anchor point;
- biasing the at least one pivot arm upwardly towards the raised position by connecting a gas spring piston between the at least one pivot arm and a second anchor point;
- and
- in response to an area below the closed damper heating up, breaking the mechanical fusible link, moving the at least one pivot arm from the generally horizontal position upwardly via the gas spring piston and engaging the overlying damper and pushing the damper to the open position, thereby exhausting hot air from the fan assembly without the aid of the motor or fan.
2 more elements
Dependencies are inferred from the claim text.