Patent Application
20150136790
The present disclosure relates generally to off-road vehicles, and more particularly, to a fluid storage tank assembly for an off-road vehicle.
Certain off-road vehicles are powered by diesel engines which produce exhaust gas. The exhaust gas may include undesirable byproducts, such as nitrogen oxides (NOx), carbon monoxide, and particulate material. To reduce emissions of such byproducts, vehicle exhaust systems may spray diesel exhaust fluid (DEF) from a DEF tank (e.g., fluid storage tank) into the flow of exhaust gas. Because of the substantial size of some off-road vehicles (e.g., a tractor) that utilize DEF, a hose may be coupled to a first fill spout on the DEF tank to improve the ease with which the tank may be filled. More specifically, in some embodiments, the DEF tank may include a second fill spout located on a different side of the off-road vehicle from the fuel fill spout. Thus, the hose may be coupled to the first fill spout of the DEF tank to enable the DEF and fuel to be replenished from the same side of the off-road vehicle. For example, one end of the hose may be disposed about an outer diameter of the fill spout, a hose clamp may be disposed about an outer diameter to the hose to couple the hose to the fill spout, and the hose may be routed through the vehicle to the same side of the vehicle as the fuel fill spout. However, if the coupling between the hose and the DEF tank loosens, for example during cold temperatures, DEF may leak at the coupling point.
Certain embodiments commensurate in scope with the originally claimed invention are summarized below. These embodiments are not intended to limit the scope of the claimed invention, but rather these embodiments are intended only to provide a brief summary of possible forms of the invention. Indeed, the invention may encompass a variety of forms that may be similar to or different from the embodiments set forth below.
In a first embodiment, a method for manufacturing a fluid storage tank assembly for an off-road vehicle includes disposing a support ring within a cavity of a rotational mold, in which the cavity is shaped to form a fill spout of the fluid storage tank assembly; and flowing a liquid polymeric material within the rotational mold such that the liquid polymeric material enters the cavity, directly contacts the support ring, and bonds to the support ring as the liquid polymeric material hardens.
In a second embodiment, a fluid storage tank assembly for an off-road vehicle, includes a first fill spout comprising a support, wherein the first fill spout is formed from a polymeric material in a rotational molding process, the support ring is bonded to the polymeric material during the rotational molding process, and the first fill spout is configured to couple to a hose to enable the fluid storage tank assembly to be filled from a first side of the off-road vehicle.
In a third embodiment, a fluid storage tank assembly for an off-road vehicle, manufactured by a process that includes rotating a rotational mold filled with a liquid polymeric material such that the liquid polymeric material enters a cavity configured to form a fill spout and bonds to a support ring disposed within the cavity as the liquid polymeric material harden.
These and other features, aspects, and advantages of the present invention will become better understood when the following detailed description is read with reference to the accompanying drawings in which like characters represent like parts throughout the drawings, wherein:
One or more specific embodiments of the present disclosure will be described below. 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,” “the,” and “said” 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. Any examples of operating parameters and/or environmental conditions are not exclusive of other parameters/conditions of the disclosed embodiments.
As discussed above, the use of diesel engines in off-road vehicles may generate undesirable byproducts (e.g., nitrogen oxides, carbon monoxide, and particulate material). Accordingly, the exhaust system of some off-road vehicles may spray diesel exhaust fluid (DEF), which is stored in a DEF tank, into the exhaust to reduce such byproducts. In some embodiments, to provide sufficient DEF for large off-road vehicles, a DEF tank may store between 150-250 liters of DEF. One example of a large off-road vehicle is a Steiger Tractor, made by CNH Global N.V. of Amsterdam, Netherlands. A Steiger Tractor may have an axle width of approximately 90 inches and a wheelbase of approximately 154 inches.
To facilitate filling the DEF tank of such a substantial off-road vehicle, a hose may be coupled to a fill spout of the DEF tank to enable the DEF tank to be filled from a more convenient location. For example, in some embodiments, the hose may enable the DEF tank to be filled from the same side of the vehicle as the fuel tank. However, external factors, such as changes in temperature, may cause the coupling between the hose and the fill spout to loosen, which may enable DEF to leak through the coupling. For example, a DEF tank formed out of a polymeric material, such as thermoplastic, may shrink relative to the hose in cold weather, thereby loosening the coupling.
Additionally, the polymeric material used to form the DEF tank may be relatively pliable. Thus, the hose may be forced into the inner diameter of the fill spout to provide structural support for the fill spout. In some embodiments, the hose may be coupled to the fill spout by mechanically cleaning out the fill spout and forcing the hose or a support insert into the inner diameter of the fill spout. More specifically, the opening of the fill spout may be partially or completely obstructed by the polymeric material (e.g., thermoplastic) used to mold the DEF tank. Thus, the fill spout may be unobstructed by mechanically cleaning (e.g., drilling) the opening. However, when the fill spout is mechanically cleaned out, debris and/or residue is produced, which may be left within the DEF tank.
Accordingly, one embodiment of the present disclosure provides a method for manufacturing a DEF tank assembly that substantially reduces or eliminates the possibility of DEF fluid leakage and/or substantially reduces or eliminates the possibility of debris collection within the DEF tank. More specifically, the method may include disposing a support ring within a cavity of a rotational mold such that the cavity is shaped to form a fill spout of the fluid storage tank assembly and flowing a liquid polymeric material within the rotational mold such that the liquid polymeric material enters the cavity, directly contacts the support ring, and bonds to the support ring as the liquid polymeric material hardens. The method may further include attaching a hose around an outer diameter of the fill spout to enable the fluid storage tank assembly to be filled with a fluid. Accordingly, the support ring, which is bonded to the fill spout of the DEF tank, provides structural support for the fill spout, thereby substantially reducing or eliminating the possibility of DEF leakage. For example, the support ring may reduce the amount of shrinkage of the fill spout during cold temperatures, thereby maintaining the dimensions of the fill spout. Additionally, the support ring is bonded to the polymeric material of the fill spout during the molding process to provide a well-defined (e.g., unobstructed) opening into the DEF tank. As a result, the process of removing material from the inner surface of the fill spout is obviated. Thus, as will be described in more detail below, the techniques described herein may improve the reliability of a DEF tank. Although the present techniques are generally described in relation to a DEF tank, the techniques described herein may additionally be utilized in other storage tanks, such as fuel tanks, grain tanks, fertilizer tanks, and the like.
With the forgoing in mind, it may be useful to describe a DEF tank assembly incorporating the techniques disclosed herein. Accordingly,
As described above, the vehicle's exhaust system may spray DEF from the DEF tank 12 into an exhaust flow to reduce undesirable byproducts. More specifically, as shown in
More specifically, the DOC housing 26 receives exhaust 40 expelled by the engine 42 and directs the exhaust 40 into the DOC 28. The DOC 28 receives the exhaust and catalyzes the oxidization of carbon monoxide to carbon dioxide by using excess oxygen in the exhaust 40. In addition, the DOC 28 uses excess oxygen to catalyze the conversion of hydrocarbons to water and carbon dioxide. In certain embodiments, the DOC 28 may use ceramics and/or metals (e.g., platinum or palladium) to catalyze the oxidization of the hydrocarbons and carbon monoxide molecules. Thus, the DOC 28 receives raw exhaust 40 and outputs catalyzed exhaust 44 with reduced concentrations of hydrocarbons and carbon monoxide.
The DOC housing 26 then directs the catalyzed exhaust 44 to the mixer 30. In the mixer 30, the injector 32 sprays DEF 34 from the DEF tank 12 into the exhaust 44. The DEF 34 is a solution used to reduce NOx within the exhaust 44. For example, in certain embodiments, the DEF 34 may include an aqueous urea solution that undergoes thermal decomposition and hydrolysis within the exhaust system 24 to produce ammonia, which the SCR 38 uses to convert the NOx into nitrogen and water. Thus, the mixer 30 supplies a well-mixed exhaust solution 46 (e.g., a mixture of the exhaust 44 and DEF 34) to the SCR module 38. The SCR module 38 receives the exhaust solution 46 and uses the distributed DEF 34 to reduce the NOx concentration in the exhaust gas. Finally, the SCR module 38 sends processed exhaust 48 with a reduced NOx concentration through the exhaust pipe 18 to be released into the atmosphere.
Returning to
As depicted, the DEF tank assembly 12 includes a tank body 49 to store DEF, a hose 50 coupled to a first fill spout 52, and a second fill spout 54. In certain embodiments, portions of the DEF tank assembly 12 (e.g., the tank body 49, the first fill spout 52, and/or the second fill spout 54) may be formed of a polymeric material, such as thermoplastic or thermosetting plastic, via rotational molding. Although rotational molding is disclosed herein, other suitable molding techniques, such as injection molding, may be utilized in alternative embodiments.
More specifically, the second fill spout 54 enables the DEF tank 12 to be filled from a first side (e.g., right side) of the vehicle 10. In addition, the fuel tank 15 may be filled via the fuel fill spout 16. However, as depicted, the fuel fill spout is positioned on a second side (e.g., left side) of the vehicle 10. Accordingly, as described above, the hose 50 may be coupled to a second fill spout and routed through the vehicle body 14 to enable the DEF tank 12 to also be filled from the second side (e.g., left side). In other words, improving convenience, an operator may replenish both the DEF tank 12 and the fuel tank 15 from the same side of the vehicle, thereby reducing the duration associated with replenishing the DEF and fuel.
The first fill spout 52, which is not explicitly depicted in
To reduce DEF leakage from the coupling between the hose 50 and the first fill spout 52, the hose 50 is secured to the outer surface of the first fill spout 52 by a hose clamp 58 and/or molded ridges 60 on the outer surface of the first fill spout 52. More specifically, the hose clamp 58 provides an inward force around the outer surface of the hose 50, and the molded ridges 60 provide frictional resistance against the inner surface of the hose 50, thereby blocking movement of the hose 50 relative to the first fill spout 52. Additionally, the molded ridges 60 engage the inner surface of the hose 52 to block fluid flow from the coupling.
Furthermore, a support ring 62 is bonded to the polymeric material 64 of the first fill spout 52 to provide structural support to the first fill spout 52. For example, because the support ring 62 is more rigid than the polymeric material 64, the support ring 62 may reduce deformation of the fill spout 52 under the pressure of the hose clamp 58, thereby establishing a tight seal between the outer surface of the first fill spout 52 and the inner surface of the hose 50. Furthermore, the support ring 62 may experience less variation in size (e.g., shrinkage) due to changes in the environment (e.g., cold temperatures), which may improve the reliability of the coupling between the hose 50 and the fill spout 52. In some embodiments, the support ring 62 may be formed from steel, other metallic materials, or the like. As depicted, the polymeric material 64 is molded to the contours 66 of the support ring 62. In some embodiments, the support ring 62 is bonded to the first fill spout 52 during the molding process (e.g., rotational molding) of the DEF tank 12.
In the depicted embodiments, the hose 50 is secured to the outer surface of the fill spout 52. Additionally or alternatively, the hose 50 may be secured within the inner diameter of the fill spout 52. That is, the inner surface of the fill spout 52 may be disposed about the outer surface of the hose 50.
One embodiment of a rotational mold 68 that may be used to form the first fill spout 52 is depicted in
To form the first fill spout 52, the support ring 62 is secured within the cavity 71 by the plug 72 while liquid polymeric material 64 (e.g., thermoplastic resin or thermosetting resin) is flowed into the mold 68. In the depicted embodiment, the support ring 62 is secured between the plug 72 and the outer shell 70 such that the ring 62 may be molded to the distal end of the fill spout 52. In other embodiments, the support ring 62 may be secured to mold 68 at a different location, thereby molding the support ring 62 another portion of the tank 12, such as an intermediate portion of the fill spout 52 or the tank body 49.
During the rotational molding process, the mold 68 is rotated (e.g., spun) to adhere the liquid polymeric material to the walls of the cavity 71, to the contours 66 of the support ring 62, and/or to the surface of the plug 72, as depicted in
After the polymeric material 64 flows into the rotational mold (e.g., covers the cavity 71, the support ring 62, and/or the plug 72), the polymeric material 64 hardens (e.g., via a cooling process) and the DEF tank 12 is removed from the mold 68, as depicted in
More specifically, the outer shell 70 may be removed from the DEF tank 12 and the plug 72 may be extracted from the DEF tank 12. In some embodiments, the plug 72 may be pulled through the opening 55. In the depicted embodiment, because the diameter of the plug 72 is larger than the diameter of the opening 55, the plug 72 may be formed from an elastic material, such as rubber, to enable the plug 72 to be removed from the tank 12 through the opening 55. In other embodiments, the plug 72 may be removed through another opening in the tank 12. Once the first fill spout 52 is formed, the hose 50 may be coupled to the fill spout 52, as shown in
Based on the techniques described above,
The technical effects of the present disclosure include improving the reliability of the DEF tank 12. More specifically, the technical effects may include substantially reducing or eliminating fluid leakage through the coupling between the hose 50 and the fill spout 52 on the DEF tank 12. In some embodiments, such technical effects results from bonding a support ring 62 to the fill spout 52 during molding of the fill spout 52 to provide structural support for the fill spout 52. For example, the support ring 62 may substantially reduce or eliminate the possibility of the coupling between the fill spout 52 and the hose 50 loosening undesirably (e.g., during cold temperatures or under pressure from the hose clamp 58). Additionally, the reliability of the DEF tank 12 may be improved by substantially reducing or eliminating the mechanical cleaning process used to define the opening 55. Instead, the support ring 62 may be molded into the fill spout 52 to well-define the opening 55 and provide structural support for the fill spout 52.
This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal language of the claims.
