This disclosure relates generally to fog-type dust suppression systems and, more particularly, to a housing for a nozzle used in such dust suppression systems.
Fog-type dust suppression systems typically use a pneumatic nozzle that mixes air and water to create a fog. This fog may be used to agglomerate and remove airborne dust particles from various material handling and processing operations at a variety of material handling points. For example, these systems may be configured for use in truck dumps, rail dumps, reclaim tunnels, crushers, screens, stack outs, ship loaders, truck loading silos and conveyor transfer points.
Some fog-type dust suppression systems utilize water and compressed air to produce a dry fog that has droplets smaller than 10 μm in size. One type of pneumatic nozzle for creating this dry fog is an ultrasonic atomizing nozzle that has convergent/divergent venturi. This convergent/divergent venturi is configured to create a standing shockwave that atomizes the incoming water into ultra-fine water droplets. These droplets agglomerate to like size dust particles or particulate matter 10 μm or smaller. The slightly wetted dust particles then become heavy enough to be removed from the air and fall back into the process.
Nozzles of fog-type dust suppression systems are often exposed to their operating environments. During operation, such exposure typically does not result in dust build-up on the nozzle because the suppression system itself creates sufficient vibration to be self-cleaning. Flow of air from the nozzle tip further provides further self-cleaning. However, when these suppression systems are not operating the nozzle may be subject to build-up through exposure to its operating environment. Because of the complex geometry of the nozzle, such build-up may be difficult to clean and may also impede proper operation of the system.
According to an aspect of the disclosure, a pneumatic assembly includes a nozzle and a housing. The housing selectively encloses the nozzle. The housing has a body that includes a first end and a second end opposite the first end. The body partially defines an interior space in which the nozzle is configured to be disposed. The body further defines a first aperture at the first end and a second aperture at the second end. The body is elongate along an axis that extends through both the first aperture and the second aperture. The housing also includes a cover assembly that is coupled to the first end of the body. The cover assembly selectively blocks the first aperture and further defines the interior space. Additionally, the housing has a piston that is disposed in the interior space and secured to the nozzle. The piston defines a gas inlet, a liquid inlet, and an outlet fluidly connected to both the gas inlet and the liquid inlet. The housing further includes a biasing member attached to the piston. The biasing member is configured to exert a biasing force on the piston in a first direction parallel to the axis. This biasing force biases the nozzle to a retracted position in which the nozzle is entirely disposed within the interior space. The biasing member is further configured such that when pressurized gas flows through the second aperture of the body, the biasing force on the piston is overcome. When the biasing force is overcome, the piston moves in a second direction opposite the first direction to dispose the nozzle in an extended position. In the extended position, at least a portion of the nozzle extends past the cover assembly and is positioned outside the interior space.
According to another aspect of the disclosure, a housing for a pneumatic nozzle has a body. The body includes a first end and a second end opposite the first end. The body partially defines an interior space in which the nozzle is configured to be disposed. The body further defines a first aperture at the first end and a second aperture at the second end. The body is elongate along an axis that extends through both the first aperture and the second aperture. The housing also includes a cover assembly that is coupled to the first end of the body. The cover assembly selectively blocks the first aperture and further defines the interior space. Additionally, the housing has a piston that is disposed in the interior space and secured to the nozzle. The piston defines a gas inlet, a liquid inlet, and an outlet fluidly connected to both the gas inlet and the liquid inlet. The housing further includes a biasing member attached to the piston. The biasing member is configured to exert a biasing force on the piston in a first direction parallel to the axis. This biasing force biases the nozzle to a retracted position in which the nozzle is entirely disposed within the interior space. The biasing member is further configured such that when pressurized gas flows through the second aperture of the body, the biasing force on the piston is overcome. When the biasing force is overcome, the piston moves in a second direction opposite the first direction to dispose the nozzle in an extended position. In the extended position, at least a portion of the nozzle extends past the cover assembly and is positioned outside the interior space.
According to a third aspect of the disclosure, a method for protecting a pneumatic nozzle during non-operational periods uses a housing configured to protect the pneumatic nozzle. The housing includes a body having a first end and a second end opposite the first end. The body partially defines an interior space in which the nozzle is configured to be disposed. The body further defines a first aperture at the first end, and a second aperture at the second end. The body is elongate along an axis that extends through both the first aperture and the second aperture. The housing also includes a cover assembly coupled to the first end of the body. The cover assembly selectively blocks the first aperture and further defines the interior space. Additionally, the housing includes a piston disposed in the interior space and secured to the pneumatic nozzle. Further, the housing includes a biasing member attached to the piston. The method includes a step of exerting a biasing force on the piston in a first direction parallel to the axis so as to bias the nozzle to a retracted position in which the nozzle is entirely disposed within the interior space. The method also includes a step of overcoming the biasing force on the piston by flowing pressurized gas through the second aperture of the body. Further, the method includes a step of moving the piston in a second direction opposite the first direction to dispose the nozzle in an extended position in which at least a portion of the nozzle extends past the cover assembly and is positioned outside the interior space.
The foregoing summary, as well as the following detailed description of illustrative embodiments of the housing for a nozzle of the present application, will be better understood when read in conjunction with the appended drawings. For the purposes of illustrating the housing for a nozzle of the present application, there is shown in the drawings illustrative embodiments. It should be understood, however, that the application is not limited to the precise arrangements and instrumentalities shown. In the drawings:
Aspects of the disclosure will now be described in detail with reference to the drawings, wherein like reference numbers refer to like elements throughout, unless specified otherwise. Certain terminology is used in the following description for convenience only and is not limiting.
Referring to
With reference to
The housing also includes a cover assembly 60 that is coupled to the first end 42 of the body 40. The cover assembly 60 selectively blocks the first aperture 48 and further defines the interior space 46. Cover assembly 60 may include a cover 62 that is secured between a cap 64 and a ring 66. Ring 66 and to cap 64 may be screwed together by screws 65 so as to form a clamp around cover 62. With reference to
With reference to
Both the system liquid line 84 and the system gas line 88 may be disposed in a flexible conduit 90. A connector 92 connects the flexible conduit 90 to an adaptor base 94 of the housing 30. Adaptor base 94 may be threaded into an adaptor body 96, which in turn mates with the adaptor cap 98.
The housing 30 further includes a biasing member 100 that fits onto the piston 70. For example, biasing member 100 may be disposed circumferentially about the body of piston 70 and abut the circumferential flange 71 of piston 70. The biasing member 100 is configured to exert a biasing force on the piston in a first direction D parallel to the axis. The biasing force of the biasing member 100 may be overcome such that the piston 70 moves in a second direction U that is opposite the first direction D. For example, biasing member 100 may be a spring, such as a stainless steel compression spring. Such a spring may have an overall length of 2 inches and a compressed length of 0.65 inches. Its spring rate may range from 40 to 50 pounds, such as between 43 and 45 pounds, and its load rate may rand from 55 to 65 pounds, such as between 59 and 61 pounds.
During operation of the nozzle 20, liquid, such as water, passes through the system liquid line 84 and gas, such as compressed air, passed through the system gas line 88. The liquid and gas enter into housing 30 via connector 86 and connector 85, respectively. Liquid flows into tube 80, while gas passes into the interior space 46 of the housing 30. From tube 80, liquid flows into inlet 74 of piston 70 through to the nozzle 20. From the interior space 46, gas passes into inlet 72 of the piston 70 through to the nozzle 20 where it mixes with the liquid to form a fog. For example, nozzle 20 may be configured to mix liquid, such as water, and gas, such as compressed air, to form a dry fog formed of droplets smaller than 10 μm in size.
Prior to gas entering the interior space 46, biasing member 100 exerts a biasing force on the piston 70 in first direction D so as to bias the nozzle 20 to its retracted position such that the nozzle 20 is entirely disposed within the interior space 46. As the gas flows into the interior space 46, the gas increases the pressure within interior space 46 such that the biasing force of the biasing member 100 is overcome. As this biasing force is overcome by the pressure of the gas, the piston 70 moves in second direction U such that the nozzle 20 is disposed in its extended position. In its extended position, nozzle 20 extends through the slits 68 in the cover 62 such that at least a portion of the nozzle 20 extends past the cover assembly 60 and is positioned outside the interior space 46. In this way, the gas has at least two functions: (1) to mix with the liquid to form a fog; and (2) to actuate the nozzle 20 into its extended position.
When the liquid and gas stop flowing into the assembly 10, pressure within the interior space 46 decreases such that the biasing force of biasing member 100 is no longer overcome. Because the biasing force is no longer overcome, piston 70 moves in first direction D such that nozzle 20 returns to its retracted position. As nozzle 20 moves from its extended position to its retracted position, the edges 62b proximate the slits 68 scrap against the nozzle 20 thereby cleaning the nozzle. Accordingly, when the assembly 10 is not in operation, nozzle 20 is protected by cover assembly 60 from dust build-up due to exposure to its operating environment.
Similar to the description outlined above in relation to
Prior to gas entering the interior space 46, biasing member 100 exerts a biasing force on the piston 70 in first direction D so as to bias the nozzle 20 to its retracted position such that the nozzle 20 is entirely disposed within the interior space 46. Further, plates 162a, 162b are biased closed by a biasing member (not shown), such as a spring.
As the gas flows into the interior space 46, the gas increases the pressure within interior space 46 such that the biasing force of the biasing member 100 is overcome. As this biasing force is overcome by the pressure of the gas, the piston 70 moves in second direction U. As piston 70 moves in second direction U, push rod 166 also moves in second direction U, pressing its inclined surface 165 against the inclined surface 167 of cam 168. As the inclined surfaces 165, 167 slide against each other, plate 162b is rotated outward about axis C. Gear 164b, which is attached to plate 162b, rotates with plate 162b. Because gear 164b is meshed with gear 164a, which is attached to plate 162a, plate 162a also rotates outward about axis C so as to form gap G.
As piston 70 moves in second direction U, nozzle 20 also moves through gap G into its extended position. In its extended position, at least a portion of the nozzle 20 extends past the cover assembly 160 and is positioned outside the interior space 46. Thus, in conjunction with cover assembly 160, the gas has at least three functions: (1) to mix with the liquid to form a fog; (2) to actuate the plates 162a, 162b before nozzle 20 contacts plates 162a, 162b; and (3) to actuate the nozzle 20 into its extended position.
As with the configuration depicted in
Features of the disclosure which are described above in the context of separate embodiments may be provided in combination in a single embodiment. Conversely, various features of the disclosure that are described in the context of a single embodiment may also be provided separately or in any subcombination.
Changes could be made to the embodiments described above without departing from the broad inventive concept thereof. It is understood, therefore, that this disclosure is not limited to the particular embodiments disclosed, but it is intended to cover modifications within the spirit and scope of the present disclosure as defined by the claims.
This application claims the benefit of U.S. Patent Application Ser. No. 62/150,033 filed Apr. 20, 2015, the disclosure of which is hereby incorporated by reference as if set forth in its entirety herein.
Number | Date | Country | |
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62150033 | Apr 2015 | US |