Quick change adjustable track center front hub assembly and method of use

The quick-change adjustable track center front hub assembly is secured to a spindle axle of a sprint car by a friction drive bearing system located between the spindle axle and the front hub assembly. The bearings are spaced apart to provide increased side and torsional load carrying capability. In addition, the hub includes a section of external splines for accepting at least one spacer and a wheel center section both having internal splines for mating with the external splines on the hub. A single lug nut connects to the outboard end of the hub for securing the spacers and wheel center sections to the front hub assembly to provide a quick-change arrangement not found before in sprint-type cars. A brake rotor is attached to the hub inboard of the spacers and wheel center section, thus allowing unimpaired accessibility to the wheel center section and spacers for quick-changing and adjusting the track center of the front wheels of the sprint-type cars.

FIELD OF THE INVENTION

This invention relates broadly to the field of motor sports, and more particularly relates to a quick-change adjustable track center front hub assembly for sprint cars.

Problem

It is a problem in the field of sprint cars to have a quick-change front hub assembly that provides adjustable track center capabilities for the front wheels of the cars. For about the past 15-20 years manufacturers of sprint cars have had a quick-change rear hub assembly that adjusts the track center, both outwardly and inwardly, of the rear wheels relative to the centerline of the car. This has been achieved by using splined axles and tapered or flat spacers that are secured onto the axle. Then the rear rim, which also has a splined center section for mating with the splined axle, is secured onto the axle with a single large lug nut. The tapered and flat spacers are used to adjust the track center of the rear hub assembly inwardly or outwardly relative to the centerline of the car. Additionally, rims and rim offsets are utilized to further adjust the track center of the rear wheel assemblies. However, nothing to date has addressed the lack of adjustable track center for the front wheels of a sprint car.

Further, an additional problem with present day front hub assemblies found in sprint cars is the fact that the rear wheels are secured with a single large lug nut, yet the front wheels are secured with four to five smaller lug bolts, thus requiring different tools to remove each. This further handicaps any quick front wheel replacement for present day racers.

Additionally, with the ongoing development of technology in sprint car racing, the cars race at faster speeds, thus causing increased side loads, vertical loads, and torsional loads on the bearings and related parts of the front hub assemblies. Yet, the arrangement, number, and spacing of these bearings within the hub assembly has not changed to counter these increased load forces, thus wheel assembly failures are likely to occur and safety of racers will be jeopardized with the continued bearing and hub arrangements found in today's sprint cars.

Also, with the recent development of front left side braking, followed by front right side braking, brake discs or rotors are now found attached to the center section of each rim half of each wheel. In addition, calipers that are located over these rotors further add to the mechanical clutter of these front hub assemblies. Thus, additional time must be spent removing the calipers from the rotors prior to removing and changing the front wheels. These recent developments further impair any design or development towards a quick-change front hub assembly for these sprint cars.

Therefore, there is a need for a quick-change front hub assembly that provides an adjustable track center for the front wheels of sprint cars, while providing front end braking capabilities, and that are affordable to manufacture.

Solution

The above-described problems are solved and a technical advance is achieved in the art by the present quick-change adjustable track center front hub assembly. The quick-change adjustable track center front hub assembly includes a hub that has a splined section for accepting splined spacers and a splined wheel center section that can be positioned respective to each other in differing arrangements to provide varying distances of track center for each individual front wheel. This allows a user of the quick-change adjustable track center front hub assembly to quickly adjust the track center of each front wheel, a feature that has not been available until now.

In addition, the quick-change adjustable track center front hub assembly includes a single lug nut that has the same dimensions of the rear lug nut, thus solving the problem of needing different tools to change the front and rear wheels of the sprint cars. The quick-change adjustable track center front hub assembly, further includes a frictional drive bearing system that includes a cap screw and torque nut, such that when tightened, they further provide the force for tightening the races of the bearings, which then cause the races to grip around the spindle axle and the hub in a frictional drive bearing system.

The quick-change adjustable track center front hub assembly can also be used with existing sprint car front spindles without having to change axles or spindles to accommodate the assembly. The quick-change adjustable track center front hub assembly further may include optional front brake disc rotors that are inboard from the adjustable portion of the quick-change adjustable track center front hub assembly so that the wheel and the track center of each wheel can be changed without having to remove the calipers from the brake rotor.

In addition, the quick-change adjustable track center front hub assembly includes a bearing configuration that supports the side and torsional loads found in today's sprint cars. The configuration includes separating with distance the farther most inboard and outboard bearings and including additional bearings where warranted to provide additional support for these increase loads.

Further, the track center adjustment is provided by using removable spacers that offset the track center or width of the front wheels of the sprint car from the centerline of the car. These spacers can be arranged relative to each other and the wheel center section in a desired fashion to provide track center adjustment in a quick-change environment.

SUMMARY

The invention provides a front hub assembly for use on a spindle axle of a sprint car for providing quick-change and adjustable track center of a front wheel, including: a hub having an inboard end and an outboard end and an external surface and an internal surface, the external surface having external splines that run substantially parallel to the major axis of the hub, the external splines located between the inboard end and the outboard end of the hub; at least two bearings spaced apart from each other by a distance, each of the at least two bearings having an inner race and an outer race, the inner race securingly contacting the spindle axle and the outer race securingly contacting said internal surface of the hub; at least one spacer located between the inboard end and the outboard end of the hub having internal splines for mating with the external splines of the external surface of the hub; a cap screw for connecting to the outboard end of the spindle axle for securing said at least two bearings to the spindle axle; and a lug nut for connecting to the outboard end of the hub for securing the at least one spacers to the front hub assembly. Preferably, the hub is substantially cylindrically shaped. Preferably, the internal surface of the hub has an inner diameter greater than the outer diameter of the spindle axle. Preferably, the inboard end further comprises a flanged structure for attaching a brake rotor to the hub.

Preferably, the hub comprises a material selected from the group consisting of aluminum, aluminum alloys, wrought aluminum, magnesium, titanium, nickel, zinc, and alloys of materials. Preferably, each of the at least two bearings is between ⅛ inch to about 1 inch in width. Preferably, each of said at least two bearings is ½ inch in width. Preferably, the front hub assembly further includes a snap ring located around the spindle axle inboard of the at least two bearings. Preferably, the front hub assembly further includes an axel spacer located between the at least two bearings for providing the distance between the at least two bearings on the spindle axle. Preferably, the at least two bearings further comprises two bearings adjacent to each other outboard from a single bearing separated by the axle spacer. Preferably, the front hub assembly further includes a wheel center section located between the inboard end and the outboard end of the hub, the wheel center section having internal splines for mating with the external splines of the external surface of the hub.

DETAILED DESCRIPTION OF THE DRAWINGS

In accordance with the present quick-change adjustable track center front hub assembly (“front hub assembly”), the front hub assembly may be used with all sprint cars, including micro or mini sprint cars. The track center means the distance between the center line of a wheel and the centerline of the car. The centerline of a car means the major axis of a car that runs from the front to the rear of the car. The term inboard is a term that means a component or element is nearer to or towards the centerline of the car and the term outboard is a term that means a component or element is farther from or away from the centerline of the car. The wheel center section and brake rotor as described below are optional elements of the front hub assembly and are described to show the environment of these components. They are not required elements of the front hub assembly.

FIG. 1illustrates an embodiment of the front hub assembly100and includes a hub102that has preferably a threaded end for accepting lug nut104that secures an optional wheel center section106to the hub102. The front hub assembly100optionally includes a brake rotor108for use with calipers of a braking system (not shown).

FIG. 2illustrates an exploded view of the front hub assembly100depicting the hub102which has an inboard end121which points towards the centerline of the car and an outboard end123which points away from the centerline of the car. Hub102further has an external splined portion120that runs substantially parallel along the major axis of the hub102between the inboard end121and the outboard end123. The wheel center section106includes internal splines126(shown inFIG. 6) that mate with the external splined portion120of the hub102when the wheel center section106is slid over the outboard end123of the hub102as shown inFIG. 1. The front hub assembly100further includes at least one spacer110for spacing or adjusting the track center of the wheel center section106inboard or outboard from the centerline of the car.FIG. 2illustrates two spacers110,112for adjusting the track center of the wheel center section106. The spacers preferably include internal splines (shown inFIG. 7) that mate with the external splined portion120of the hub102. The spacers110,112slide over the outboard end123of the hub102as shown inFIG. 1. In one aspect, the spacers110,112have widths of one-half inch. In another aspect, the spacers110,112have widths of varying sizes, such as one-quarter inch and three-quarter inch, to further increase the flexibility of the track center adjustments of the present front hub assembly100. Additional spacers110,112may also be employed for further flexibility regarding adjusting the track center of the wheel center section106. In one embodiment of the present front hub assembly100, the track center may be increased up to one inch per each front wheel, for a combined total outboard track center adjustment of two inches.

FIG. 2also illustrates an embodiment of the front hub assembly100where two spacers110,112are located outboard from the wheel center section106. In this embodiment the wheel center section106is first slid over the external splined portion120of the hub102and then the spacers110,112are slid over the external splined portion120. This places the wheel center section106nearest to the inboard end of the hub102.

FIG. 2illustrates further illustrates a cap screw118that connects with spindle axle116that are shown and described in more detail below. Spindle axle116supports bearings148,150, and152(shown inFIG. 10), and the spindle axle116and bearings148,150, and152support and are located inside of hub102of the front hub assembly100. Bearings148,150, and152typically include outer races149,151, and153, respectively, that contacts the internal surface of the hub102. Also, bearings148,150, and152typically include inner races (not shown) that contact the spindle axle116. Spindle axle116is typically the outboard extension from the spindle of an axle (not shown) that supports the front hub assembly100. In addition, brake rotor108attaches to the inboard end121of the hub102.

FIG. 3illustrates an embodiment200of the front hub assembly where one spacer110is located outboard from the wheel center section106and one spacer312is located inboard from the wheel center section106. In this embodiment, spacer312is a flat spacer and not tapered, as shown for spacers110,112. In another embodiment, spacer312can be replaced by spacer110,112. In another embodiment, spacers110and112are interchangeable and can be used on either side of the wheel center section106. In this embodiment, the wheel center section106is spaced outboard from the centerline of the car a distance equal to the spacer312relative to embodiment100. This embodiment is achieved by sliding the spacer312over the outboard end123of the hub102and engaging the internal splines of the spacer312to mate with the external splined portion120of the hub102. Then the wheel center section106is slid over outboard end123of the hub102and engaging the internal splines126of the wheel center section106to mate with the external splined portion120of the hub102. This is followed by sliding the spacer110over the outboard end123of the hub102and engaging the internal spines of the spacer110to mate with the external splined portion120of the hub102. This embodiment adjusts outwardly the track center of the wheel center section106from the centerline of the car relative to embodiment100.

FIG. 4illustrates an embodiment300of the front hub assembly100where two spacers312,452are located inboard of the wheel center section106. Spacers312,452are placed onto the hub102first then followed by the wheel center section106. This embodiment adjusts outwardly the track center of the wheel center section106from the centerline of the car relative to embodiments100and200. In this embodiment, spacer312and452are flat spacers. In another aspect of the front hub assembly100, spacers110,112may be used in the place of spacers312,452.

FIG. 5illustrates hub102with spacers110,112, but without the wheel center section106. The inboard end121of hub102has a flanged structure114for mating with the brake rotor108as shown inFIG. 1. Flanged structure114includes a plurality of bolt holes124for accepting bolts to attach the hub102with the brake rotor108. Lug nut104is shown secured to the outboard end123of the hub102. Typically, the lug nut104has an inner threaded portion for connecting to the hub102, which also includes an outer threaded portion that is near or at the outboard end123of the hub102. In addition, the internal surface103of the hub102can be seen.

FIG. 6illustrates an aspect of a wheel center section106having an inboard side128and an outboard side130. Preferably, wheel center section106includes a plurality of bolt holes132for securing the two rim halves as described below. In addition, internal splines126can be seen for mating with external splined portion120of the hub102.FIG. 7illustrates an aspect of spacers110,112including internal splines140for mating with the external splined portion120of the hub102. In one embodiment, spacers110,112have a tapered end134and a flared end138for aligning one next to another in an arrangement as shown inFIG. 5. In another embodiment, spacers110,112may possess a flared end138but not a tapered end134, or neither depending on the desired application. Furthermore,FIG. 8illustrates a lug nut104having an outboard portion shaped144for use by a wrench or tool to remove or replace the lug nut104. In one embodiment, lug nut104also has a tapered end142for purposes of fitting with the flared end138of spacers110,112.

FIG. 9illustrates a spindle axle116and includes an end164that is connected to or is the outward extension of an axle for supporting the front hub assembly100. Spindle axle116includes areas162,160, and158for supporting at least one or all of bearings148,150, and152. In one aspect, the spindle axle116is a one inch press fit bore spindle. The spindle axle116can also have different diameters as well.FIG. 10illustrates a spindle axle116and bearings150and152separated from bearing148by axle spacer156. Bearings148,150, and152are secured and kept in position on spindle axle116by the races of the bearings being in contact with the spindle axle116and the force exerted on the bearings148,150, and152by the cap screw118and the torque washer154, which when tightened, provides force for tightening the races of the bearings148,150, and152that cause the races of the bearings148,150, and152to grip around the spindle axle116and the internal surface103of the hub102(shown inFIG. 5) in a friction drive type manner, thus securing the hub102onto the spindle axle116. By tightening the cap screw118and torque washer154, the inner races of the bearings tighten against each other, which cause the bearings148,150, and152to secure the spindle axle116to the hub102.

Additionally, snap ring146further provides frictional forces for retaining bearings148,150, and152between the spindle axle116and the internal surface103of the hub102. The space between bearings150and152and bearing148created by axel spacer156provides the necessary distance for handling the increased side and torsional loads exerted on the front hub assembly100. Specifically, the present front hub assembly100can handle continuous side loads of up to 6,500 pounds, whereas the prior art designs could barely sustain continuous side loads of 4,200 pounds. The spacing of the bearings provides better and greater resistance to torsional or torque loads on the hub102, thus also providing a greater side load resistance.

In one aspect of the present front hub assembly100, the wheel center section106is attached, bolted, connected, or affixed to an inboard wheel halve and an outboard wheel halve that together form a vehicle wheel for accepting a tire. In another aspect of the front hub assembly100, the wheel center section106is formed as a one-piece vehicle wheel for accepting a tire. In one aspect, information related to these wheel configurations and designs can be found in U.S. patent application Ser. No. 10/029,790 filed 29 Oct. 2001 by Darnell, said application published 01 May 2003 under Publication No. US 20030080609 A1, now abandoned, and incorporated by reference herein.

The dimensions of the components of the front hub assembly100are sized to fit all vehicles that have a spindle axle116, such as conventional mini and micro sprint cars. The axle diameter is typically one inch, but can be larger or smaller depending on the application. In one aspect the spindle axle116is one inch in diameter, but can be different diameters as well. The materials for the components of the front hub assembly100are typically those metals and compositions that are commonly found in the industry. The spindle is typically made of 4140 carbon steel, or some other equivalent strength material, such as 4130 chrome-moly or other high strength high carbon content steel. In addition, the hub102, lug nut104, axel spacer156, cap screw118, torque washer154, spacers110,112, are made of a materials selected from aluminum, aluminum alloys, wrought aluminum, magnesium, titanium, nickel, zinc, or alloys of these. An exemplary material is T6 6061 aluminum. The brake rotor108is preferably made of 1008 low carbon steel, or equivalent strength material.

The bearings are preferably roller bearings, needle bearings and the like, and may also be any other type of bearings suitable for the purposes of front hub assembly100. In one embodiment, the bearings150,152are approximately 0.625 inner diameter and 1.375 outer diameter, and a 0.4375 width, or the equivalent, such as commonly known bearings with part number 1623 with a seal part number of 2 rs (two rubber seals). In another embodiment, the bearings151,153have different widths and may also be double side-load bearings, and the like. The selection of the bearings150,152may be based on the side loads that will be experienced in the sprint car. In one embodiment, bearing148is preferably a two inch outer diameter, one inch inner diameter with a 0.625 inch width.

In addition to the aforementioned aspects and embodiments of the present front hub assembly100, the present invention further includes methods for adjusting the track center of the front hub assembly100.FIG. 11illustrates an embodiment of a process400for increasing the track center of the front wheels of a sprint car. In step402, the single lug nut104is removed completely from the hub102of the front hub assembly100. This may be accomplished by using the tool or wrench that fits the rear wheel lug nut of the sprint car. In step404, the spacers110,112are removed completely from the front hub assembly100by pulling or sliding them off of the splined portion120of the hub102. In step406, the wheel center section106is removed completely from the front hub assembly100by pulling or sliding it off of the splined portion120of the hub102. Then in step408both spacers312,452are placed back on the front hub assembly100by sliding them back on the splined portion120of the hub102. In step410, the wheel center section106is then placed back on the front hub assembly100by sliding it back on the splined portion120of the hub102. In step412, the lug nut104is threaded back on the hub102and tightened with a tool. In step414, the process is repeated until both of the front wheels of the car are adjusted as desired. In another aspect of step408one of the spacers312,452are placed onto the hub102and the other one of the spacers110,112is placed onto the hub102following the placement of the wheel center section106onto the hub102.

FIG. 12illustrates another embodiment of a process500for decreasing the track center of the front wheels of a sprint car. In step502, the single lug nut104is removed completely from the hub102of the front hub assembly100. This may be accomplished by using the tool or wrench that fits the rear wheel lug nut of the sprint car. In step504, the wheel center section106is removed completely from the front hub assembly100by pulling or sliding it off of the splined portion120of the hub102. In step506, the spacers312,452are removed completely from the front hub assembly100by pulling or sliding them off of the splined portion120of the hub102. In step508, the wheel center section106is then placed back on the front hub assembly100by sliding it back on the splined portion120of the hub102. Then in step510both spacers110,112are placed back on the front hub assembly100by sliding them back on the splined portion120of the hub102. In step512, the lug nut104is threaded back on the hub102and tightened with a tool. In step514, the process is repeated until all of the front wheels of the car are adjusted as desired. In another aspect of step508one of the spacers312,452is placed onto the hub102and the other one of the spacers110,112is placed onto the hub102following the placement of the wheel center section106onto the hub102.

FIG. 13illustrates another embodiment of a process600for producing the front hub assembly100. In step602a hub is provided. In one embodiment, hub102is manufactured by a lathe-turned process, such as a live tooling lathe, to form the profile and the inner bearing profiles against the internal surface103for seating the bearing150,152of the hub102. Then the inboard end121of the hub102is milled in a milling process and the bolt holes124are preferably drilled and tapped. In one embodiment, the external splined portion120of the hub102is manufactured by a single-point milling operation on a rotory table, or other suitable processes. In another embodiment, the external splined portion120of the hub102is manufactured by a single-point shaper in the vertical axis. Preferably, the hub102is manufactured as a single piece. In addition, the hub102can be manufactured as a multi-component piece.

In step604, the inboard bearings150,152are press fit into the inboard end121of the internal surface103of the hub102. In step606, the axle spacer156in positioned in the internal surface103of the hub102adjacent to the bearings150,152. In step608, bearing148is slip fitted into the internal surface103of the outboard end of the hub102adjacent to the axle spacer156. Then in step610, the snap ring146is snapped into place against an inner groove (not shown) milled or lathed into the internal surface103of the hub102towards the inboard end.

In step612, the spindle axle116is inserted into the hub102. Then in step614, the cap screw118and the torque washer154are attached to the outboard end of the spindle axle116and tightened, thus tightening bearings148,150, and152and axle spacer156such that they become frictionally engaged both the hub102and the internal surface103of the hub, thus securing the hub102to the spindle axle116. In step616, the process is repeated for another front hub assembly100.

Although there has been described what is at present considered to be the preferred embodiments of the present quick-change adjustable track center front hub assembly, it will be understood that the front hub assembly can be embodied in other specific forms without departing from the spirit or essential characteristics thereof. For example, different wheel center sections or wheels may be used, other than those described herein. Also, other materials for the various components may be used other than those described herein without departing from the inventive novelty described herein. The present embodiments are, therefore, to be considered in all aspects as illustrative and not restrictive. The scope of the invention is indicated by the appended claims rather than the foregoing description.