The present invention is related to wheel hubs used on fully floating rear drive axle of a vehicle. More particularly the present invention is related to polygonal hub for a vehicle for any application which is with optimum material content and achieves more strength to weight ratio.
Hubs are mounted on the axle housing spindle through locking arrangement assembled with bearings and seals. The hub lies between drive gearing and wheel end parts like rims, brake drums and tires. The basic functions of axle hub are,
Axle hubs primarily in circular in shape made of casting material. But these hubs are subjected to below mentioned loads effective in different directions during the vehicle operations;
The existing axle hub design methodology is generally based on following factors:
Due to these conventional design factors, the existing hubs are not optimal as;
To achieve the required strength and stiffness characteristics, of the hub, the hub designers are using more material which leads to increase in weight of hub for the application having lower strength to weight ratio. The prior art concepts of hub are not optimally stiff enough but are voluminous and hence heavy.
Japanese patent JP2003285603A discloses circular hub with elliptical shaped central cavity in casting which will provide the required stiffness and strength. But apart from strength, these hubs are voluminous and hence carry more loads. These hubs behave in similar way as circular shaped hubs. But the main drawback of this design is that the frontal portion is covered with bigger outer circular shape having maximum section modulus and more strength than the rear portion of the hub (i.e. back side of the flange) causing the stress concentration in this region.
Korean patent KR20090050233A describes circular shaped hub with additional triangular ribs provided in bolt area. This will provide the more stiffness to the flange area which will be beneficial in cornering and vertical loading to avoid the deflection. But as the central portion of the hub is circular these hubs have always less strength to weight ratio.
The main object of the present invention is to provide wheel hub of polygon structure and more particularly the hexagon structure.
Another object of the present invention is to provide hexagonal hub that achieves the maximum strength with optimized material content.
Another object of the present invention is to provide hexagonal hub that achieves the more part life with lower material content having more strength to weight ratio.
Accordingly invention provides a polygonal hub for fully floating rear drive axle of a vehicle of used in the break drum and wheel assembly comprising a hub which rotates on the supporting member of axle drive shaft assembled with inner bearing and outer bearing in the in the housing therein with seals lubricants to enable rotate freely about an axis and are fixed in position with the said member; the complete wheel end assembly then packed with lock nut; the said hub having a flange carries wheel bolt which provides seating for brake drum and wheel rim and tightened with the use of wheel nut; the said hub is formed by casting having central portion, which is the main portion of hub, characterized in that the said central portion is made of hexagonal in shape to carry safely the various loads (i.e. vehicle GVW, cornering, braking & torque load) during different operating conditions of the wheel.
The present invention will lead to better understanding when read in conjunction with the following drawings, wherein
Referring to
The hub assembly (14) comprises of hub (4) which rotates on the member (10) assembled with inner bearing (5) and outer bearing (7). These bearing help to rotate about an axis and are fixed in position with member (10). This complete wheel end assembly is then packed with lock nut (12). The axle hub (4) serves as housing for bearings (5 & 7), seals (6 & 11) and lubrication media. The hub flange (15) carries wheel bolt (2) which provides seating for brake drum (1) and wheel rim and tightened with the use of wheel nut (3). The hub (4) is formed by casting.
Referring to
The integrated hexagons (18) provide mesh like structure to increase the hub stiffness with minimum mass content. This mesh like structure is formed due to load lines (23) which transfer and cancel the loads, reducing loads and stress intensity in this area. The intersecting hexagon edge (21) is so arranged that they are parallel to central hexagon from two sides (22). During vertical loading (load āPā) the face to face intersecting hexagon forms elliptical shaped load line (23), reducing the concentrating loading in the hub. Thus, the main central hexagon with intersecting hexagons increases the strength of hub assembly by 10% more than that of the circular hub.
Also the intersecting hexagons are cancelling torque reactions created due to axle shaft (8), which is coupled with hub through the flange bolt (9). The axle shaft (8) transfer the torque loads received from vehicle driveline, which is transferred to wheels through the hub. Referring to
In addition to the significant reduction in the highest stress levels, experienced by hub (4), the location of stress levels is vastly improved using the hexagonal structure. The repositioning and reduced stress region in the hub is shown in
Thus a polygonal hub for fully floating rear drive axle of a vehicle used in the break drum and wheel assembly comprising a hub (4) which rotates on the supporting member (10) of axle drive shaft assembled with inner bearing (5) and outer bearing (7) in the in the housing therein with seals and lubricants to enable rotate freely about an axis and are fixed in position with the said member (10); the complete wheel end assembly is then packed with lock nut (12). The said hub having a flange (15) carries wheel bolt (2) which provides seating for brake drum (1) and wheel rim and tightened with the use of wheel nut (3). The said hub (4) is formed by casting having central portion (17), which is the main portion of hub (4). The invention involves providing hexagonal shape to the central portion instead of circular shape of said hub. This makes hub 10% more strength to carry the various loads (i.e. vehicle GVW, cornering, braking & torque load) during different operating conditions of the wheel. Further a small hexagon formed on the each side of the said central hexagonal hub at outer half section peripheral. The said small hexagon outer half section of the peripheral intersects with central hexagon (17). The inner half portion of the hexagon (18) merges with central hexagon section (17). The intersecting hexagon edge (21) is so arranged that the two sides of the said small hexagon are parallel to central hexagon from two sides (22) respectively. The smaller hexagon (18) joins the central hexagon (17) with hub flange (15), giving the required strength and stiffness as shown in
The technical advantages of the present invention are:
The hexagonal hub of the present invention can be used for variety of vehicles such as transportation vehicles like truck, buses, two wheelers, cars and also for farm equipments. The possible combinations of polygons to have polygonal hub structure are:
It is to be understood that the present invention is not limited in its application to the details of the construction and to the arrangements of the components as mentioned in the above description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced and carried out in various ways. Also, the terminologies used herein are for the purpose of description and should not be regarded as limiting.
Number | Date | Country | Kind |
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2871/MUM/2011 | Oct 2011 | IN | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/IN2012/000673 | 10/10/2012 | WO | 00 | 4/9/2014 |