Patent Application
20120129445
The present invention is directed to the field of heating ventilation and air conditioning using forced air. More particularly, the present invention is directed to control of airflow through a ventilation duct at a ventilation register.
Fully sealing off airflow through a ventilation register would save energy (heating or cooling) by securely preventing airflow through registers in rooms that are not being used, for example, an unused guest bedroom. Air that leaks from a nominally closed ventilation register represents wasted energy.
The damper function of typical residential ventilation registers is ineffective to completely block airflow, and fails to completely stop heating or cooling of unused spaces. Some commercial ventilation registers may have a damper function that can more fully block airflow, but these are expensive and are not economically viable as a popular choice to replace the typical cheap ventilation registers used in residential central air handling systems.
A number of proposals have been made for modifying or blocking airflow at a ventilation register. U.S. Pat. No. 4,520,715 to Coomes et al. discloses an apparatus that would cover room air registers. U.S. Pat. No. 5,213,543 to Clarino discloses an aircap cover assembly for ceiling registers. Published patent application US 2008/0160904 by Yi et al. discloses a vent cover function of paired male and female diffusers that combine to block airflow. U.S. Pat. No. 5,596,392 to Hawkins et al. discloses a register filter having an elastic band 34. U.S. Pat. No. 1,274,996 to Davis discloses a mechanically engaged removable cover for hot air flues. U.S. Pat. No. 5,479,984 to Easterbrook et al. discloses a magnetic affixed removable shut-off panel. U.S. Pat. No. 5,435,781 to Kitchens discloses a register with a functional mode to block airflow. U.S. Pat. No. 6,776,709 to Moore, Jr. et al. discloses a selectively closable floor vent cover.
The various vent covering or blocking schemes suffer from at least one of several disadvantages. Some are too expensive (as compared to estimated monetary savings from reduced energy waste) for homeowners to justify their widespread adoption. Some cannot be retrofit to an existing typical residential ventilation register, and would require replacement of the existing register. Some are impractical or simply unsightly.
What is needed is a practical energy saving measure to block flow of air through a residential ventilation register that does not cost so much as to offset the energy savings. Making energy savings economically advantageous (i.e., affordable) and practical, improves chances of adoption of such a measure by substantial numbers of people.
One aspect of the flow stop is a sheet of impermeable material shaped as a bag having a closed end and an open end opposed to the closed end, where the sheet has an elastic member fixed about the open end.
Another aspect of the flow stop is a sheet of impermeable material shaped as a bag having a closed end and an open end opposed to the closed end, where an elastic member is fixed across a portion of the closed end.
Yet another aspect of the flow stop is blockage of air using an impermeable sheet formed substantially of polymer material.
Still another aspect of the flow stop is blockage of airflow using an impermeable sheet comprising nonwoven fabric.
According to one embodiment, the flow control is for use in combination with a ventilation register having a faceplate with a vent and skirt extending outwardly from the face plate for insertion into a forced air duct outlet. The flow control is adapted for disposition about the skirt for blockage of airflow from the duct outlet. The flow control device has an impermeable and pliable sheet material, a clamp structure, and a noise suppression member. The clamp structure is secured along the periphery of the sheet material to secure the sheet material to the skirt. The noise suppression member is secured laterally across the sheet material to apply tension force to the sheet material.
The flow control is intended for use with a ventilation register and according to another embodiment has an air impermeable bag, a peripheral tension structure, and a motion control tension structure. The bag has a first, closed end and a second, open end. The peripheral tension structure includes an elastic band that is connected about a peripheral edge of the open end of the bag and is sized to provide a gripping fit of the open end about a portion of the ventilation register. The motion control tension structure is connected to the closed end of the bag to apply tension force across the sheet when the bag is fitted to the register and subject to fluid pressure when blocking airflow. The motion control tension structure includes at least one piece of elongated elastic material disposed across the closed end and having opposed ends attached at, or near to, the peripheral tension structure.
Referring to
The body 110 is shaped to have a generally bag-like form, albeit a shallow bag that is wider along at least one lateral dimension than it is deep. The elastic band 130 provides the spring force that holds the body 110 of the flow stop 100 in place on a ventilation register. The elastic strips 140, 150 apply tension force across the closed end 120. The tension force applied to the closed end 120 by the elastic strips 140, 150 serves to prevent any excess material of the closed end 120 from moving unduly so as to make noise.
Plastic bags (and sheet materials, generally) are notorious for the noise they can generate when being moved about. The tension force provided by the elastic strips 140, 150 serves to mitigate this noise by minimizing how much the flow stop moves when fluid pressure is applied across its closed end 120 while stopping airflow. Although the flow stop is meant to be installed in rooms that are not being used, noise generated by a moving bag is not isolated to that room because the sound is conveyed efficiently through the ductwork into other, occupied rooms. Applying tension force across the closed end 120 effectively suppresses this noise.
The flow stop is useful in sealing a typical ventilation register in a central air system. The first embodiment flow stop according to
According to an exemplary embodiment, the elastic band 130 is about 3 inches wide, and the elastic strips 140, 150 are 2 to 3 inches wide. The substantial width of the elastic band 130 provides reinforcement around sharp edges of the diffuser. The substantial width of the elastic strips 140, 150 helps the flow stop accommodate larger range of ventilation register sizes, and approach the ideal where one size of flow stop fits all sizes of ventilation registers.
Referring to
To show the relationship of the elastic strips 140, 150 to the elastic band 130,
This construction is appropriate for affixing the elastic materials to the body via heat or adhesive bonding or sewing. Many manufacturing processes are suitable to adhere the fabric to the elastic on a fixture that stretches out the elastic elements to substantially their fullest extent, so that when released from the fixture the flow stop will have sufficient elasticity to be placed around diffusers ranging in size from as small as 8 in.×4 in. to as large as 16 in.×8 in.
According to an alternate embodiment, refer to
A pair of elastic strips 640, 650 are each disposed across the closed bottom end 120. The elastic strips 640, 650 apply tension force across at least a portion of the closed end 120. The tension force applied to the closed end 120 by the elastic strips 640, 650 serves to prevent any excess material of the closed end 120 from moving unduly so as to make noise.
As shown in
In the above embodiments the elastic about the circumference is described and shown as being on an opposed face of the sheet from where the laterally disposed elastic members. This placement on opposed faces is not critical to the practice of the invention, which may alternatively be embodied to have all elastic components disposed on a single side of the impermeable sheet.
A flow stop bag is advantageously formed of materials impervious to air. Polymers are a class of materials that typically block airflow well. For example, nylon film (commonly used to make consumer-grade balloons) and polyethylene film (commonly used to make grocery bags) are both strong, inexpensive, and airtight. Other polymers may be suitable for the flow stop, depending upon burst strength and impermeability. Although flash spun polypropylene sheets (sold under the name Tyvek®) have excellent resistance to tearing, they are breathable and, thus, should be combined with a second film, such as a polymer coating or metallic film to make the sheets impermeable to air.
Embodiments of a flow stop for blocking flow of air through a ventilation register have been described. It will be understood by those skilled in the art that the present invention may be embodied in other specific forms without departing from the scope of the invention disclosed and that the examples and embodiments described herein are in all respects illustrative and not restrictive. Those skilled in the art of the present invention will recognize that other embodiments using the concepts described herein are also possible. Further, any reference to claim elements in the singular, for example, using the articles “a,” “an,” or “the” is not to be construed as limiting the element to the singular.
