Patent Application
20090242664
This application relates generally to a surface mounted deicing device for spraying anti-icing agents on a paved transport surface such as a road or bridge. The device sprays anti-icing agents in a liquid form through spray nozzles. The anti-icing agents comprises, among others, magnesium chloride (MgCl2), potassium acetate, calcium magnesium acetate, and the like. The deicing device may help reduce accidents caused by ice covered roads or bridges and thus increase the safety margin for travelers on the road.
Many deicing devices have been developed to apply anti-icing agents to a transport surface such as a road or bridge. The devices are often surface mounted to the transport. The devices are also flush with the transport surface to avoid interference with vehicles travelling on the transport surface, lessen the probability for the devices to be damaged.
The deicing devices are often installed directly into the road surface by using adhesives or bonding agents when the road is paved. If one or more components of the spray head gets damaged, the spray head is typically removed, which may be difficult or expensive. Alternatively, if the spray head needs to be serviced for defective functions, it may disrupt the traffic.
Additionally, when the road or bridge is repaved, the surface mounted deicing device may be below the transport surface. Alternatively, when the paved surface is worn down, the deicing device may protrude above the surface. This situation may accelerate the surface wear of the deicing device. Furthermore, the deicing device often collects dirt or debris that may affect the spray of the anti-icing agents.
Therefore, there remains a need for deicing devices that are adjustable and flexible. There still remains a need for reducing surface wear of the deicing device to extend service life of the deicing device. There remains a further need for reduced contamination when the deicing device is in service.
Embodiments of the invention pertain to techniques for increasing flexibility and adjustability in deicing devices. Spray heads of the deicing devices may be rotatable for covering targeted transport surface. The height of the deicing device may be adjustable to extend a top surface of the deicing device to be flush with the transport surface when the transport road is repaved or resurfaced. A flow rate or droplet size of the anti-icing agent spray may be adjusted to meet desired requirements. A spray angle of spray channels may also be adjusted to cover small or larger surface area. The deicing device may also include rounded corners in the jet channels to be less likely to collect and retain dirt or debris. The deicing device may have improved dimensional stability and wear resistance.
Embodiments of the invention include a deicing device for spraying anti-icing agents over a transport surface, such as paved road or bridge, to protect the transport surface from ice formation. The deicing device that is surface mounted to the transport surface has a pavement sensor. The sensor is used to determine when the deicing device is turned on and off to spray the anti-icing agents. The deicing device comprises a supporting housing, a spray puck having a plurality of nozzles and jet channels connected to the nozzles for spraying anti-icing agents, a lock ring to immobilize the spray puck within the supporting housing, and an O-ring for sealing the anti-icing agents from leaking. The spray puck can be rotated within the supporting housing to change a spray direction. The spray puck is then locked in a changed spray direction, for example, by using a plurality of fasteners.
In additional embodiments of the invention, at least one insert may be disposed into one of the nozzles. The insert may be shaped in a form of a tube. An inner diameter of the insert has a variable size to allow adjustment in flow rate. The jet channels connected to the nozzles have a variable angle for adjusting spray direction vertically. This angle may be set at various values when the spray puck is machined. The jet channels on the spray puck have a cross section with round corners. In a preferred embodiment of the invention, the cross section has a parabolic shape.
In still more embodiments of the invention, the spray puck with nozzles and channels comprises a plastic that is substantially non-hygroscopic and wear resistant. For example, the device may include a polyacetal plastic such as Delrin® from DuPont. Polyacetal is less sensitive to dimensional changes and degradation in mechanical properties because of less moisture absorption. Polyacetal also has wear resistance and low friction.
In further embodiments of the invention, the bottom of the supporting housing may be configured to be attachable to the top of the supporting housing to extend a top surface of the device to be flush with the transport surface. The overall thickness of one supporting housing may vary from another supporting housing.
Additional embodiments and features are set forth in part in the description that follows, and in part will become apparent to those skilled in the art upon examination of the specification or may be learned by the practice of the invention. A further understanding of the nature and advantages of the present invention may be realized by reference to the remaining portions of the specification and drawings.
An exemplary deicing device is illustrated in
In
The nozzle 106 may be connected between the inlet 108 and jet channel 104 to allow the anti-icing agents to be supplied in from the inlet and sprayed through the nozzle 106 and the jet channel 104 as shown in
An O-ring is a loop of elastomer with a round cross-section used as a mechanical seal. It is seated in a groove and compressed during assembly of the spray puck 102 and the support housing 202 and creates a seal at the interface to prevent the anti-icing agents from leaking.
The spray puck 102 and the supporting housing 202 may comprise a plastic that is non-hydroscopic and wear resistant. The plastic may be a polyacetal, that is often referred by a trade name Delrin manufactured by DuPont. This material has similar wear resistance like nylon, but has better resistance to water absorption and thus better dimensional stability than nylon. Another benefit of using the plastic is its inherently resistance to corrosion, especially with anti-icing agents around. The spray puck and supporting housing may also comprise a metal, such as stainless steel, or any composite and the like.
The deicing device allows the spray puck 102 to be rotated within the support housing 202. For example, the fasteners 304 on the deicing device may be loosen to allow the movement of the spray puck 102 within the support housing 202. Once the spray puck 102 is rotated to a desired position to maximize the coverage area of the transport surface, the spray puck 102 is locked into the position by the lock ring 302. One way of holding the lock ring 302 is to tighten a set of fasteners 304 in the mounting holes 210 of the support housing 202.
In one embodiment, a pavement sensor may be attached to the deicing device. The pavement sensor is a digital device designed to provide current information on pavement conditions. The sensor may measure road surface temperature, moisture, humidity, traffic of a transport surface and the like. The sensor may also include algorithms that allow to predict if frost dew is likely to form on the road. The active capabilities of the sensor allow road maintenance personnel to receive accurate freeze-point calculations of a road surface and to detect frost or ice on the road. The sensor generates all the data needed to activate the deicing device 502.
A valve connected to the inlet of supporting housing 202 may be controlled by the pavement sensor through a controller. The controller may determine the time to turn on/off the valve. The controller may also determine spray time, flow rate, flow pressure, etc.
The deicing device 502 may be placed into a recess area from the transport surface and bonded to the transport surface with a bonding agent, such as an adhesive, epoxy or the like. A groove at the bottom of the supporting housing 202 accommodates the bonding agent to form a strong bond between the transport road 508 and the supporting housing 202. The deicing device 502 is flush mounted to the transport surface 504. Installation assembly and wear indicators are described in a patent application U.S. Pat. No. 6,102,306, entitled “Multifunctional Flush Surface Nozzle,” by Bernard J. Ask, Tom Ask, which is incorporated herein by reference for all purposes.
In a specific embodiment of the invention, when the transport road is repaved or resurfaced, a second supporting housing 202 of the deicing device 502 may be stacked to the first supporting housing 202 to extend the top surface of the deicing device 502 to be flush with the transport surface 504. The bottom of the supporting housing 202 is grooved to allow the supporting housing 202 to sit on the top of the supporting housing 202. The dual stacking of the supporting housing 202 may be bonded by an adhesive, or mechanical fasteners, and the like. The overall thickness of the second supporting housing may vary from the first supporting housing.
Thus, having described several embodiments, it will be recognized by those of skill in the art that various modifications, alternative constructions, and equivalents may be used without departing from the spirit of the invention. Examples of possibly variations may include but not limited to varying shapes and dimensions of the spray puck, nozzles, inserts, jet channels, techniques of stacking of supporting housings, and the like. Accordingly, the above description should not be taken as limiting the scope of the invention, which is defined in the following claims.
