Patent Application
20230058575
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 gear lifts 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 gear lifts 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 may allow the assembly to widen the wheelbase of the vehicle.
Portal gear lifts typically include sealed housings (boxes) that 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. Additionally, excess heat may damage seals, causing them to fail and allowing oil, etc., to leak from the box.
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 assembly for an all-terrain vehicle or a utility task vehicle. The assembly may comprise a portal gear box housing with a first opening for receiving the end of a vehicle axle, a second opening for an output shaft, and a set of gears to link the input shaft to the output shaft. To mitigate against the effects of heat build-up in the housing, one or more of the housing walls includes a plurality of heat-radiating fins effective to radiate heat from the housing at a faster rate than would be radiated in the absence of the fins.
The fins may extend outward from the adjacent outer surface of the housing, or they may extend inward. The fins may be formed by removing metal from one or more of the walls of the housing.
The fins may be removably attached to one or more of the walls of the housing, or they may be formed integrally with one or more of the walls of the housing.
The fins may comprise a generally rectangular, planer surface extending radially from a wall of the housing.
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 assembly for an all-terrain vehicle or a utility task vehicle. The assembly may comprise a portal gear box housing with a first opening for receiving the end of a vehicle axle, a second opening for an output shaft, and a set of gears to link the input shaft to the output shaft. To mitigate against the effects of heat build-up in the housing, one or more of the housing walls includes a plurality of heat-radiating fins effective to radiate heat from the housing at a faster rate than would be radiated in the absence of the fins. This transfers heat from the housing and from the gears and other components and materials inside of the housing, thus reducing the temperature of the assembly during use.
The fins may extend outward from the adjacent outer surface of the housing, or they may extend inward. Regardless of their orientation, the fins may be positioned such that a heat transfer fluid, which may be air, or oil, or another heat transferring fluid, may flow around the fin to facilitate heat transfer.
The fins may be formed by removing metal from one or more of the walls of the housing. The metal may be removed from the inside or the outside of the housing wall.
The fins may be removably attached to one or more of the walls of the housing, or they may be formed integrally with one or more of the walls of the housing.
The fins may comprise a generally rectangular, planer surface extending radially from a wall of the housing. In some embodiments, the fins have a more trapezoidal shape.
Referring now to the drawings,
As indicated above, it is to be appreciated that alternative embodiments may utilize different structural details to accomplish similar results. For example, while the illustrated fins are surrounded by air, they may be surrounded by oil or another heat conducting fluid that is effective to promote heat dissipation from the housing through the fins.
Also, while the illustrated fins each comprise a generally rectangular, planer surface, the fins may be provided in essentially any shape effective to promote heat dissipation from the housing through the fins.
Similarly, while the illustrated fins are formed as a unitary package of fins that may be removably attached to the walls of the housing, the fins may be formed integrally with one or more of the walls of the housing.
Lastly, while the illustrated fins are formed as separate pieces of metal that are attached to the housing, the fins may be formed by removing metal from one or more of the walls of the housing.
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.
