Patent Application
20230024034
The present invention relates generally to portal wheel ends for lifting the wheels of an off road vehicle such as an all-terrain vehicle (ATV) or a utility task vehicle (UTV), and more particularly to gear-reducing portal gear boxes.
Portal boxes are used by ATV and UTV enthusiasts to raise an off-road vehicle higher above the ground so that larger tires can be run on the vehicle. In addition, since larger diameter tires cover a greater distance with each rotation, portal box assemblies typically include gear reduction so that a single rotation of the vehicle power axle results in a slightly lesser rotation of the output axle. Further, the extra length provided by the output axle also typically allows the assembly to widen the wheelbase of the vehicle.
Portal gear boxes typically are sealed to contain a fluid lubricant effective to lubricate the gears as the gears spin within the housing. Vigorous use may cause the gears and their lubricant to heat, and that heating may reduce the effectiveness of the lubricant and cause pressure to build up within the housing.
A need therefore exists for materials and methods for reducing portal gear box heating, and for avoiding, reducing, and/or relieving resulting pressure. The present invention addresses that need.
In one aspect of the invention there is provided a portal gear box system for an all-terrain vehicle or a utility task vehicle. The system may comprise:
a) a sealed portal gear box housing having an interior housing space defined by a rear wall, a front wall, and a side wall,
wherein the rear wall includes a vehicle axle opening effective to receive the end of an axle of an all-terrain vehicle or a utility task vehicle, and
wherein the front wall includes an output shaft opening effective to receive the end of an output shaft effective to power a vehicle wheel;
b) a set of gears housed in said housing and effective for linking an axle received in the vehicle axle opening to an output shaft received in the output shaft opening;
c) an output shaft operably connectable via said linking mechanism to an axle received in the vehicle axle receptacle, and effective to rotate upon rotation of the stock axle;
d) a fluid circulation loop effective to circulate a cooling fluid from a fluid output location to a fluid input location, with the fluid circulation loop being substantially external to the housing; and
e) a cooling fluid contained in the fluid circulation loop and effective to cool the temperature of components contained in the portal gear box.
In another aspect of the invention there is provided a portal gear box assembly for an all-terrain vehicle or a utility task vehicle, comprising:
a) a portal gear box housing a set of gears effective for linking an axle received in the vehicle axle opening to an output shaft received in the output shaft opening;
b) a lubricating oil contained in the portal gear box; and
c) a fluid circulation loop effective to circulate a cooling fluid from a fluid output opening to a fluid input opening, with the fluid circulation loop being substantially external to the portal gear box.
In some preferred embodiments of either or both of these aspects the cooling fluid is additionally effective to lubricate components contained in the portal gear box, and thus to improve the life and/or functioning of the components.
In some preferred embodiments of either or both of these aspects the cooling and lubricating fluid is oil.
In some preferred embodiments of either or both of these aspects the fluid circulation loop includes a pump.
In some preferred embodiments of either or both of these aspects the fluid circulation loop includes a filter effective to filter the circulating fluid.
In some preferred embodiments of either or both of these aspects the fluid circulation loop passes the fluid through a radiator/cooler effective to assist with the cooling of the fluid in the fluid circulation loop.
In some preferred embodiments of either or both of these aspects the fluid circulation loop is effective to maintain the temperature of oil contained therein within the optimum temperature range of the oil.
In some preferred embodiments of either or both of these aspects the fluid circulation loop circulates cooling fluid between two or more portal gear box assemblies.
In some preferred embodiments of either or both of these aspects the cooling fluid is caused to circulate through the fluid circulation loop by a pumping action caused by the rotation of one or more gears in the set of gears.
For the purposes of promoting an understanding of the principles of the invention, reference will now be made to certain embodiments and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended, such alterations and further modifications in the described device, and such further applications of the principles of the invention as illustrated therein, being contemplated as would normally occur to one skilled in the art to which the invention relates.
As indicated above, one aspect of the present invention relates to a portal gear box system for an all-terrain vehicle or a utility task vehicle. The system may comprise:
a) a sealed portal gear box housing having an interior housing space defined by a rear wall, a front wall, and a side wall,
b) a set of gears housed in said housing and effective for linking an axle received in the vehicle axle opening to an output shaft received in the output shaft opening;
c) an output shaft operably connectable via said linking mechanism to an axle received in the vehicle axle receptacle, and effective to rotate upon rotation of the stock axle;
d) a fluid circulation loop effective to circulate a cooling fluid from a fluid output location to a fluid input location, with the fluid circulation loop being substantially external to the housing; and
e) a cooling fluid contained in the fluid circulation loop and effective to cool the temperature of components contained in the portal gear box.
Portal gear boxes are well known to the art, and typically comprise a rear wall, a front wall, and a side wall. The walls define an interior housing space. The rear wall typically includes a vehicle axle opening effective to receive the end of an axle of an all-terrain vehicle or a utility task vehicle, and the front wall typically includes an output shaft opening effective to receive the end of an output shaft effective to power a vehicle wheel. A set of gears is housed in the housing, and is effective for linking an axle received in the vehicle axle opening to an output shaft received in the output shaft opening. The input opening is typically located above the output shaft, and the gears are sized to provide an appropriate gear reduction. This arrangement allows the user to run larger wheels by raising the vehicle and accounting for the differences in rotational axle speed that is required. Such assemblies are typically referred to as portal gear lifts, portal gear hubs, portal gear boxes, portal gear lift boxes, or some other similar name, and for the purposes of this disclosure any such similar name may be used to refer to assemblies of this type.
As with many mechanical systems, lubrication is desirable, so the interior housing space is substantially sealed to allow a lubricating fluid to be contained therein. However, and particularly in harsh environments, the lubricating fluid may become overheated, thus reducing its useful life and performance.
The present invention provides effective cooling of the interior of a portal lift gear box and the components contained therein by circulating a cooling fluid through the box.
The circulating cooling fluid is preferably a lubricating fluid, such as a natural or synthetic lubricating oil, that additionally lubricates the portal gear box components. However, in some embodiments the cooling fluid may be another fluid, such as water, ethylene glycol, or propylene, or the like, and may contain protection additives.
The fluid is contained in a circulation loop that passes outside the outside the box, where the cooling fluid is cooled before being returned to the box. The cooling fluid circulation loop may function to circulate cooling fluid to only one portal gear box, or it may circulate cooling fluid to two or more portal gear box assemblies.
The cooling fluid may be caused to circulate through the circulation loop by the power of a pump. The pump may be external to the box, or components within the box may be used to provide the pumping action.
The cooling fluid may be cooled by passing through a radiator or some other cooling structure. The radiator or other cooling structure may cool the fluid for one or more circulation loops.
The cooling fluid may be passed through a filter to remove contaminating particles from the fluid. The filter may filter the fluid for one or more circulation loops.
The cooling fluid may exit the portal gear box through an output structure such as an exit port, and may return to the portal gear box through an input structure such as an input/entrance port.
Referring now to the drawings,
While the invention has been illustrated and described in detail in the foregoing description and drawings, the same are to be considered as illustrative and not restrictive in character, it being understood that only certain preferred embodiments have been shown and described, and that all changes and modifications that come within the spirit of the invention are desired to be protected.
Additionally, it is to be appreciated that the present invention may comprise or consist essentially of any or all of the described ingredients in their disclosed amounts, and that any or all of the ingredients, amounts, features, elements, and/or embodiments disclosed herein may be combined with any or all of the other ingredients, amounts, features, elements, and/or embodiments disclosed herein to provide an invention that comprises or consists essentially of such ingredients, amounts, features, elements, and/or embodiments.
The grammatical device “and/or” (such as in “A and/or B”) is used in this disclosure to mean A alone, or B alone, or both A and B. Additionally, the term “substantially perpendicular” means within 5° of perpendicular, and the term “substantially forward” (or rearward) of perpendicular means at least 10° forward (or rearward) of perpendicular.
