Patent Application
20220349615
This section is intended to introduce the reader to various aspects of art that may be related to various aspects of the present disclosure, which are described below. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of the various aspects of the present disclosure. Accordingly, it should be understood that these statements are to be read in this light, and not as admissions of prior art.
Heating, ventilation, and air conditioning (HVAC) systems are generally configured to provide temperature controlled air to an internal space. For example, various temperature and pressure control devices of the HVAC system may be controlled to generate an air flow having a particular temperature and to direct the air flow (e.g., via ductwork) to the internal space. In certain operating and/or ambient conditions, or for other reasons, portions of the HVAC system may encounter unnecessarily high temperatures. Traditional HVAC systems may employ traditional dampers having traditional fuse devices intended to enable actuation of a blade or other feature to close an air flow path of the ductwork in response to the unnecessarily high temperatures. Unfortunately, it is now recognized that traditional fuse devices may be difficult to install, maintain, and/or reset. These difficulties may increase a maintenance time and cost, and can lead to improper maintenance and poor performance of the fuse device. It is now recognized that improved devices are needed.
A summary of certain embodiments disclosed herein is set forth below. It should be understood that these aspects are presented merely to provide the reader with a brief summary of these certain embodiments and that these aspects are not intended to limit the scope of this disclosure. Indeed, this disclosure may encompass a variety of aspects that may not be set forth below.
An embodiment of the present disclosure includes a damper of a heating, ventilation, and/or air conditioning (HVAC) system. The damper includes a crank configured to rotate about an axis of a shaft relative to a support, a reset arm configured to rotate about the axis of the shaft relative to the support, a spring coupled to the crank and the reset arm, and a fuse link configured to be coupled to the reset arm and the support in a set configuration and to release the reset arm from the support in response to a temperature exceeding a threshold temperature. The crank and the reset arm are configured to rotate away from the support in a first circumferential direction toward a closed configuration in response to the fuse link releasing the reset arm from the support. A spring force of the spring is configured to increase as the reset arm is rotated in a second circumferential direction opposite to the first circumferential direction beyond the set configuration and into a reset configuration.
Another embodiment of the present disclosure includes a fuse device for a damper of a heating, ventilation, and/or air conditioning (HVAC) system. The fuse device includes a crank configured to rotate about an axis of a shaft relative to a support, a reset arm configured to rotate about the axis of the shaft relative to the support, a fuse link configured to be coupled to the reset arm and the support in a set configuration and to release the reset arm from the support in response to a temperature exceeding a threshold temperature, a first spring, and a second spring. The first spring is configured to bias, in response to the fuse link releasing the reset arm from the support; the crank and the reset arm in a first circumferential direction from the set configuration to a closed configuration. The second spring is coupled to the crank and the reset arm and a spring force of the second spring is configured to increase in response to rotation of the reset arm in a second circumferential direction opposite to the first circumferential direction beyond the set configuration and toward a reset configuration.
Another embodiment of the present disclosure includes a damper of a heating, ventilation, and/or air conditioning (HVAC) system. The damper includes a damper housing defining an air flow path of the HVAC system, a shaft having a first portion extending into the damper housing and a second portion extending external to the damper housing, a reset lever coupled to the second portion of the shaft, and a fuse assembly. The fuse assembly is coupled to the first portion of the shaft and configured to rotate, in response to a temperature exceeding a threshold temperature, in a first circumferential direction from a set configuration in which the air flow path is open to a closed configuration in which the air flow path is closed. The reset lever is maneuverable to rotate the fuse assembly, via the shaft, in a second circumferential direction opposite to the first circumferential direction such that a reset arm of the fuse assembly rotates in the second circumferential direction beyond the set configuration toward a reset configuration.
Various aspects of this disclosure may be better understood upon reading the following detailed description and upon reference to the drawings in which:
One or more specific embodiments of the present disclosure will be described below. These described embodiments are only examples of the presently disclosed techniques. Additionally, in an effort to provide a concise description of these embodiments, all features of an actual implementation may not be described in the specification. It should be appreciated that in the development of any such actual implementation, as in any engineering or design project, numerous implementation-specific decisions must be made to achieve the developers' specific goals, such as compliance with system-related and business-related constraints, which may vary from one implementation to another. Moreover, it should be appreciated that such a development effort might be complex and time consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill having the benefit of this disclosure.
When introducing elements of various embodiments of the present disclosure, the articles “a,” “an,” and “the” are intended to mean that there are one or more of the elements. The terms “comprising,” “including,” and “having” are intended to be inclusive and mean that there may be additional elements other than the listed elements. Additionally, it should be understood that references to “one embodiment” or “an embodiment” of the present disclosure are not intended to be interpreted as excluding the existence of additional embodiments that also incorporate the recited features.
The present disclosure is directed to a fuse assembly for a damper used in a duct section of ductwork of a heating, ventilation, and air conditioning (HVAC) system. For example, the HVAC system may include an HVAC unit configured to condition air and to distribute the conditioned air to ductwork extending toward conditioned spaces of a building. The ductwork may include a duct section having a damper, such as a fire damper, where the damper includes a fuse assembly configured to retain the damper in an open (or set) configuration and, in response to an elevated temperature within the duct section, actuate the damper to a closed configuration. For example, the fuse assembly may include a fuse link configured to break in response to an elevated temperature, enabling actuation of certain aspects of the fuse assembly to the closed configuration. When the damper and corresponding fuse assembly are in the closed configuration, a blade of the damper may block a flow path of the duct section.
In accordance with present embodiments, the fuse assembly may include a crank configured, in certain embodiments and/or operating conditions, to rotate about an axis of a shaft relative to a support, a reset arm configured to rotate about the axis of the shaft relative to the support, and a first spring (e.g., a extension spring) coupled to and between the crank and the reset arm. The above-described fuse link may extend between a hook of the reset arm and a hook the support when the fuse assembly is in the set configuration, thereby preventing a second spring (e.g., a torsion spring) from causing rotation of the fuse assembly while the fuse assembly is in the set configuration. The fuse link may be configured to release the reset arm from the support (e.g., via a breaking of the fuse link) in response to the temperature within the duct section exceeding a threshold temperature. The threshold temperature may be defined by a material and/or geometry of the fuse link, such that the fuse link breaks in response to the elevated temperature in the duct section, thereby releasing the reset arm from the support and allowing aspects of the fuse assembly to rotate away from the support.
For example, after the fuse link breaks and releases the reset arm from the support, a spring force of the second spring (e.g., torsion spring) may cause the crank to rotate in a first circumferential direction toward the closed configuration. As the fuse assembly rotates in the first circumferential direction from the set configuration to the closed configuration, a link member coupled to and between the crank and the blade of the damper may bias the blade to close the flow path of the duct section.
After the fuse assembly is in the closed configuration, a reset lever (e.g., coupled to the shaft) extending outside of the duct section may be utilized (e.g., by an operator) to rotate aspects of the fuse assembly in a second circumferential direction opposing the first circumferential direction, such that the reset arm rotates beyond the set configuration and toward a reset configuration. For example, while the crank of the fuse assembly may be blocked from rotating beyond its normal position in the set configuration, the reset lever may enable rotation of the reset arm (e.g., via the shaft) in the second circumferential direction beyond its normal position in the set configuration and into the reset configuration, such that the hook of the reset arm and the hook of the support are closer to each other in the reset configuration than in the set configuration. The first spring (e.g., extension spring) is configured to extend in length to enable the reset arm to rotate in the second circumferential direction beyond the set configuration and into a reset configuration.
By allowing the reset arm to rotate in the second circumferential direction opposite to the first circumferential direction beyond the set configuration and into the reset configuration, a new fuse link may be more readily coupled to the reset arm and to the support. That is, the fuse link may be more readily coupled to the reset arm and to the support in the reset configuration because a distance between the hook of reset arm and the hook of the support is smaller in the reset configuration than in the set configuration. An access port in the duct section may also improve installation and maintenance by enabling the operator to couple a new fuse link to the hook of the reset arm and the hook of the support while the assembly is in the reset configuration.
The features described above, and described in additional detail below with reference to the drawings, enable improved installation procedures (e.g., setting the fuse link during first installation) and improved maintenance procedures (e.g., replacing or resetting the fuse link with a new fuse link after the fuse link releases or breaks in response to elevated temperatures in the duct section). Further, presently disclosed embodiments enable the operator to actuate the above-described fuse assembly features via an external lever, as opposed to an internal lever, which may also improve an ease of maintenance and installation procedures. These and other features are described in detail below with reference to the drawings.
Turning now to the drawings,
The HVAC unit 12 may be an air cooled device that implements a refrigeration cycle to provide conditioned air to the building 10. Specifically, the HVAC unit 12 may include one or more heat exchangers across which an airflow is passed to condition the airflow before the airflow is supplied to the building. In the illustrated embodiment, the HVAC unit 12 is an AHU, such as a rooftop unit (RTU) which conditions a supply air stream, such as environmental air and/or a return airflow from the building 10. Outdoor units, indoor units, or other conditioning schemes are also possible. After the HVAC unit 12 conditions the air, the air is supplied to the building 10 via ductwork 14 extending throughout the building 10 from the HVAC unit 12. For example, the ductwork 14 may extend to various individual floors or other sections, such as rooms, of the building 10. Terminal units 20 associated with the floors, rooms, or other sections of the building 10 may be connected to the ductwork 14 and may be configured to distribute the airflow to the floors, rooms, or other sections of the building 10. In some embodiments, the terminal units 20 may include air conditioning features in addition to, or in the alternate of, the air conditioning features of the HVAC unit 12.
In certain embodiments, the HVAC unit 12 may be a heat pump that provides both heating and cooling to the building with one refrigeration circuit configured to operate in different modes. In other embodiments, the HVAC unit 12 may include one or more refrigeration circuits for cooling an air stream and a furnace for heating the air stream. Additionally or alternatively, other HVAC equipment may be installed at the terminal units 20 or in another area of the building, such as a basement 21 (e.g., a boiler may be installed in a basement of the building 10). A control device 16, one type of which may be a thermostat, may be used to designate the temperature of the conditioned air. The control device 16 also may be used to control the flow of air from the HVAC unit 12, through the ductwork 14, to the terminal units 20, or any combination thereof. For example, the control device 16 may be used to regulate operation of one or more components of the HVAC unit 12 and/or terminal units 20. In some embodiments, other devices may be included in the system, such as pressure and/or temperature transducers or switches that sense the temperatures and pressures of the supply air, return air, and so forth. Moreover, the control device 16 may include computer systems that are integrated with or separate from other building control or monitoring systems, and even systems that are remote from the building 10.
As previously described, the system of
For example, focusing first on
When the fuse link 40 breaks, the fuse link 40 may release its coupling of the hook 43 of the reset arm 44 with the hook 41 of the support 42. Aspects of the fuse assembly 34, in response to the fuse link 40 breaking and releasing the reset arm 44 from the support 42, may be actuated via a spring force (e.g., via a torsion spring) toward a closed configuration, whereby the fuse assembly 34 causes the blade 36 of the damper 32 to close the flow path 38 in the duct section 30. While most of the torsion spring is hidden in
Further, a link member 56 of the fuse assembly 34 may be coupled to and between the crank 54 and the blade 36. The crank 54 and the link member 56 may be coupled via a pin assembly 58 such that the link member 56 can rotate relative to the crank 54 about the pin assembly 58. Further, the blade 36 may be coupled to the link member 56 via an additional pin assembly 59. Rotation of the link member 56 relative to the crank 54 about the pin assembly 58, and rotation of the blade 36 relative to the link member 56 about the additional pin assembly 59, may enable the blade 36, which extends generally horizontally in the duct section 30 while in the set configuration, to extend generally vertically in the duct section 30 while in the closed configuration. That is, in the set configuration, the blade 36 may extend generally parallel to a flow direction 39 within the flow path 38 such that the flow path 38 is open and a fluid flow is permitted. In the closed configuration, the blade 36 may extend generally perpendicular to the flow direction 39 within the flow path 38 such that the flow path 38 is closed by the blade 36.
After the damper 32 and corresponding fuse assembly 34 are in the closed configuration (e.g., after the damper blade 36 closes the flow path 38 in the duct section 30 as described above), aspects of the fuse assembly 34 may be actuated via an operator in a second circumferential direction 60 opposite to the first circumferential direction 50. For example, in
The closer distance between the hooks 41, 43 may improve ease of setting a new fuse link (e.g., to replace the fuse link 40 after it breaks) while the reset arm 44 is in the position corresponding to the reset configuration. Further, an access opening in the duct section 30 of
Focusing again on
The set configuration, the closed configuration, and the reset configuration described above are illustrated in
The torsion spring 80 in the illustrated embodiment includes an arm 84 coupled to the support 42 via upon a rivet assembly 86. Upon a breaking of the fuse link 40 in response to a temperature exceeding a threshold temperature, the torsion spring 80 may bias the crank 54 from the set configuration toward the closed configuration via the hook 37 of the torsion spring 80 extending through the opening 39 in the crank 54. For example, the fuse link 40, in the set configuration, may effectively block the torsion spring 80 from biasing the crank 54 toward and into the closed configuration (e.g., by way of the extension spring 62 extending between, and coupling to, the extension 64 of the reset arm 44 and the crank 54). After the fuse link 40 is broken, a spring force (e.g., torque) of the torsion spring 80 against the crank 54 causes the crank 54 (and the reset arm 44 via the extension spring 62) to rotate away from the hook 41 of the support 42.
As previously described, the pin assembly 58 coupling the crank 54 and the link member 56 may enable the link member 56 to rotate about the pin assembly 58 relative to the crank 54. The link member 54 may include a lip 76 that prevents over-rotation of the link member 56 relative to the crank 54. That is, the lip 76 may permit the link member 56 to rotate about the pin assembly 58 relative to the crank 54 until the link member 56 is generally in-line with the crank 54, and then may block the link member 56 from further rotation. The pin assembly 59 illustrated in
The crank 54 is also coupled to the link member 56 via the pin assembly 58. As previously described, the pin assembly 58 enables rotation of the link member 56 with respect to the crank 54. Accordingly, while the link member 56 and the crank 54 form an angle in
As shown in
After the new fuse link 100 is set, the reset lever 70 may be released back to the position illustrated in
It should be noted that in any of the embodiments illustrated in
In the illustrated embodiment, the method 200 includes rotating (block 202) a reset lever coupled to the reset arm via a shaft from the above-described closed configuration, beyond the above-described set configuration, and to a reset configuration. As previously described, rotating the reset lever such that the reset arm (via the shaft) rotates beyond the set configuration and into the reset configuration reduces a distance between the reset arm and the support (e.g., compared to the set configuration). While rotating the reset arm beyond the set configuration and into the reset configuration, a spring (e.g., extension spring) between the reset arm and the crank of the fuse assembly may extend or expand in length (e.g., such that a tension in the extension spring increases). As previously described, the reset lever may extend into an area external to the duct section such that the reset lever is accessible by the operator external to the duct section, which may improve an ease of rotating the assembly.
The method 200 also includes setting (block 204) a new fuse link onto a hook of the reset arm and onto a hook of the support while the assembly is held in the reset configuration. For example, an access port in the duct section may enable the operator to reach into the duct section and place the new fuse link onto the reset arm and onto the hook while the assembly is held in place (e.g., via the external reset lever) in the reset configuration.
The method 200 also includes releasing (block 206) the reset lever such that the reset lever and the reset arm (e.g., by way of a coupling therebetween to a shaft) rotate from the reset configuration back to the set configuration. When the reset lever is released, the extension spring extending between the reset arm and the crank may contract in length (e.g., a tension in the extension spring may be reduced) as the reset arm rotates back toward the crank and into the set configuration. After the assembly is in the set configuration, the method 200 may be complete.
One or more of the disclosed embodiments, alone or in combination, may provide one or more technical effects useful in installing and maintaining a damper for use in a duct section of ductwork associated with an HVAC system. For example, disclosed embodiments improve an ease of setting a fuse link associated with a fuse assembly of the damper, and an ease of moving the fuse assembly to a particular configuration in which the fuse link is set, as described in detail above with reference to the drawings.
While only certain features and embodiments of the disclosure have been illustrated and described, many modifications and changes may occur to those skilled in the art, such as variations in sizes, dimensions, structures, shapes and proportions of the various elements, values of parameters including temperatures and pressures, mounting arrangements, use of materials, colors, orientations, etc., without materially departing from the novel teachings and advantages of the subject matter recited in the claims. The order or sequence of any process or method steps may be varied or re-sequenced according to alternative embodiments. It is, therefore, to be understood that the appended claims are intended to cover all such modifications and changes as fall within the true spirit of the disclosure. Furthermore, in an effort to provide a concise description of the exemplary embodiments, all features of an actual implementation may not have been described, such as those unrelated to the presently contemplated best mode of carrying out the disclosure, or those unrelated to enabling the claimed disclosure. It should be appreciated that in the development of any such actual implementation, as in any engineering or design project, numerous implementation specific decisions may be made. Such a development effort might be complex and time consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill having the benefit of this disclosure, without undue experimentation.
