An illustrative damper system includes a damper blade that is configured to be positioned within a duct, such as a bypass duct of an HVAC system. A shaft is in communication with the damper blade, a torsion spring is in communication with the shaft, and a force adjustment mechanism is in communication with the torsion spring. The shaft, the damper blade, and the torsion spring may be configured such that the shaft may affect movement of the damper blade about a rotation axis and the torsion spring may provide a bias force to the shaft for biasing the damper blade toward a desired position (e.g. closed position).

In one embodiment, a system, comprising: a damper assembly, the damper assembly comprising: a structural member; at least one door pivotably coupled to the structural member; a clip connected to the damper assembly and comprising plural spring end constraining segments; a spring comprising a first end and a second end, wherein at least the first end comprises a hook, the spring coupled at the first end to one of the plural spring end constraining segments and at the second end fixably coupled to the damper assembly, the clip configured to accept a hookable connection to the spring at any one of the plural spring end constraining segments, each of the plural spring end constraining segments constraining movement of the hook, when connected thereto, during opening and closing of the at least one door, wherein the spring is at a first tension when hooked to the one of the plural spring end constraining segments and at a second tension when hooked to another of the plural spring end constraining segments.

A backdraft damper for permitting a flow of air in an outflow direction and preventing the flow of air in a backdraft direction, including a frame having a transverse opening allowing the passage of air through the frame; a plurality of blades, each blade extending across the frame and mounted to the frame about a central portion by pivot members, for rotation between an open position in which the blade allows air to flow through the frame and a closed position in which the blade blocks air from flowing through the frame, the plurality of blades including one or more first blades arranged to rotate in a first direction from the closed position to the open position; one or more second blades arranged to rotate in a second direction opposite to the first direction from the closed position to the open position; the backdraft damper further including a linkage between the one or more first blades and the one or more second blades to cause the first and second blades to together rotate between the closed and open positions; and the one or more second blades being more balanced about respective pivot members than the one or more first blades thereby to permit the one or more first blades to bias the entire plurality of blades to the closed position while being movable to the open position by the force of air flowing through the frame in the outflow direction.

A damper assembly includes a frame having an inner surface and a protrusion extending inwardly relative to the inner surface, a damper blade coupled to the frame and configured to transition between an open position and a closed position, and a latch coupled to the inner surface of the frame. The latch is configured to deform to facilitate transition of the damper blade between the open position and the closed position and to expand to capture and retain the damper blade in the closed position, the latch includes a tab segment configured to move toward the protrusion during deformation of the latch and to move away from the protrusion during expansion of the latch, and a distal end of the tab segment overlaps with a thickness of the protrusion.

A vent cover for an air duct having (a) a top surface with an aperture, (b) an actuating member extending through the aperture and operably connected to a magnet selectively engageable with the air duct, and (c) a bias means for urging the magnet towards the air duct, the actuating member movable between a securing position and a releasing position, wherein in the securing position the bias means urges the magnet towards the air duct, and in the releasing position the actuating member moves the magnet away from the air duct to allow the vent cover to be removed from the air duct.

The present disclosure relates to design and implementation of an actuating drive, typically including at least a motor, a gear mechanism, and an actuator connection, wherein the motor drives the actuator connection by means of the gear mechanism. For example, an actuating drive may include: a motor; a gear mechanism; an actuator connection, wherein the motor drives the actuator connection through the gear mechanism; and a spring suitable to act on the actuator connection independently of the gear mechanism.

A switch mechanism may include a lever holding part which is provided in a case, a turnable lever provided with a shaft part turnably supported by the lever holding part and a first arm part and a second arm part protruded from the shaft part, an urging member structured to urge the turnable lever, and a switch whose state is switched by displacement of the turnable lever. The turnable lever is attached to the lever holding part in a state that the urging member is engaged between the first arm part and the second arm part, and the urging member is movable between an engaging position, where the urging member is engaged between the first arm part and the second arm part, and an engaging release position, where the urging member is engaged with the second arm part and is disengaged from the first arm part.

There is described an actuator device comprising a single molded housing, a linear bridge feature, a spring hook retention feature, and a power spring. The single molded housing is formed by integrating the linear bridge feature across the single molded housing and the spring hook retention feature to one side of the linear bridge feature. The power spring is inserted laterally through the linear bridge feature of the actuator device. The power spring includes a spring hook at one end, and the spring hook of the power spring attaches to the spring hook retention feature of the actuator device. The power spring applies, at least in part, a torque to a control shaft coupled to the actuator device.

A single-package air conditioner appliance includes a housing defining an outdoor portion and an indoor portion; an outdoor heat exchanger assembly disposed in the outdoor portion; an indoor heat exchanger assembly disposed in the indoor portion; a compressor in fluid communication with the outdoor heat exchanger and the indoor heat exchanger; an intake conduit extending from the housing, the intake conduit defining an intake passage upstream from the indoor inlet, the intake conduit further defining a secondary inlet upstream from the intake passage to permit air thereto; a secondary air duct extending from the intake conduit outside of the housing upstream from the secondary inlet to direct air thereto, the secondary air duct defining a secondary air passage; and a damper door provided in the secondary air duct to allow air therethrough, the damper door including a spring member selectively biasing the damper door against the secondary air duct.

A standoff comprising a handle that is adjustably associated with a bracket, with the handle self-latching in relation to bracket at a desired position and at a desired quantifiable torque in relation to the bracket.