Adjustment bolt for adjusting camber angle

An adjustment bolt for adjusting the camber angle in a vehicle. The adjustment bolt includes a head, a neck, a lobe, and a threaded portion. The head is configured to provide a gripping surface for a tightening tool (e.g., pliers, wrench). The neck extends eccentrically from the bottom surface of the head and the neck has a first diameter and a first centerline. The lobe extends eccentrically outward from a bottom surface of the neck and the lobe has a second diameter and a second centerline. The threaded portion extends eccentrically outward from a bottom surface of the lobe and has a third centerline. The first centerline, the second centerline, and the third centerline are different from one another. Additionally, the lobe diameter is substantially the same as an aperture diameter for an adjustment aperture in a knuckle operably connected to the vehicle.

FIELD

The present disclosure relates generally to an apparatus for adjusting camber in a vehicle, and more specifically, to a fastener apparatus for adjusting camber in a vehicle suspension system.

BACKGROUND

The camber angle, referred to simply as camber in the automotive trade, is the variance in degrees measured between true vertical and that of the measured vertical axis of the wheel as viewed from the front or back. Most vehicles are developed and produced with camber specifications recommended and published by the manufacturer. Camber, in combination with suspension design and other wheel alignment specifications, is developed to best meet a vehicle's handling and tire wear expectations. Many vehicles do not provide for a built in method of adjusting camber. In other words, the wheel assembly may be securely attached to the suspension system, which may make adjusting the camber angle more difficult. In these vehicles, the arrangement may include a generally vertical suspension strut including a knuckle assembly operably connected to a lower portion thereof. The knuckle may then attach to a wheel spindle (which connects to the wheel). Although these vehicles may be made to have a non-adjustable camber angle, to keep a vehicle in specification for optimized handling and tire wear attributes, camber may need to be adjusted from time to time. Bolts, cam shaped washers, other fastener assemblies, and grinding bolt holes into slots have been used to mechanically alter camber on vehicles with these “non-adjustable” suspension systems. However, each suspension system may include differently sized apertures to receive the fasteners, and different sized or shaped bolts may be needed to maximize camber change for each different suspension system. This may require mechanics and/or automobile part stores to stock a number of different bolts to best serve the market.

SUMMARY

The present disclosure relates to an adjustment bolt for adjusting camber in a vehicle. The adjustment bolt may include a head, a neck, a lobe (or cam), and a threaded portion. The head may be configured to provide a gripping surface for a tightening tool (e.g., pliers, wrench). The head has a first diameter and a first centerline. The neck extends eccentrically from the bottom surface of the head and the neck has a second diameter and a second centerline. The lobe extends eccentrically outward from a bottom surface of the neck and the lobe has a third diameter and a centerline that is the same as the first centerline. The threaded portion extends eccentrically outward from a bottom surface of the lobe and has a third centerline. The first centerline, the second centerline, and the third centerline are different from one another and the lobe diameter is substantially the same as an aperture diameter for an adjustment aperture in a knuckle operably connected to the vehicle.

Other embodiments may include an adjustment assembly for adjusting the camber in a vehicle. The adjustment assembly may include an adjustment washer and an adjustment bolt configured to be inserted into the adjustment washer. The adjustment washer includes a prong extending away at a first angle from a body of the washer, and a tang extending in the opposite direction from the prong, but perpendicularly to the body of the adjustment washer. The tang is configured to be inserted into a receiving aperture on a U-bracket or flange operably connected to a vehicle suspension system. The adjustment bolt includes a head, a neck, a cam or lobe, and a threaded portion. The head forms a first end of the adjustment bolt. The neck extends eccentrically from a bottom surface of the head and is substantially cylindrically shaped and has a neck centerline. The lobe extends eccentrically from a right bottom surface of the neck, opposite of the head. The lobe is substantially cylindrically shaped and has a cam centerline. The threaded portion extends eccentrically outward from the lobe and includes a plurality of threads wrapping around an outer wall. The threaded portion has a major thread diameter corresponding to a crest to crest distance between threads on a top surface and a bottom surface of the outer wall, a root diameter corresponding to a valley to valley distance between the threads on the top surface and the button surface, and a third centerline. The first centerline, the second centerline, and the third centerline are different from one another and the major diameter is selected so that a crest of at least one thread of the plurality of threads is configured to engage a bottom inner wall of a receiving aperture of a U-bracket when the adjustment aperture is at least partially received within the receiving aperture.

Still other embodiments include a method for adjusting camber in a vehicle. The method may include sliding an adjustment washer onto an adjustment bolt. The adjustment washer includes a prong extending away at a first angle from a body of the washer, and a tang extending in an opposite direction perpendicularly to the body of the washer. The tang is configured to be inserted into a receiving aperture on a flange operably connected to a strut of a vehicle suspension system. The adjustment bolt includes a head, a neck, a lobe, and a threaded portion. The head forms a first end of the adjustment bolt. The neck extends eccentrically from a bottom surface of the head, it is substantially cylindrically shaped with a neck centerline. The lobe extends eccentrically from a right bottom surface of the neck, opposite of the head. The lobe is substantially cylindrically shaped and has a lobe centerline. The threaded portion extends eccentrically from a right bottom surface of the lobe such that along a right side surface of the adjustment bolt, the neck, the lobe and a major diameter of the threaded portion are effectively flush. Additionally, the threaded portion has a thread centerline which differs from the lobe and neck centerlines. After the adjustment washer has been inserted onto the adjustment bolt, the threaded portion of the adjustment bolt is inserted into a receiving aperture on a flange operably connected to a strut of a vehicle. Then, the tang of the adjustment washer is inserted into the receiving aperture, such that a bottom surface of the washer may be substantially flush with a first outer surface of the flange. A nut is applied to the threads of the bolt and it is loosely tightened. After the nut and adjustment bolt have been loosely tightened the tang is oriented inward or outward horizontally depending on the kind of camber change required. The adjustment bolt is then rotated within the receiving aperture to obtain a desired camber angle.

These and other aspects and advantages of embodiments of the disclosure will become apparent from the detailed description and drawings that follow.

DETAILED DESCRIPTION

The present disclosure relates to an adjustment bolt for adjusting the camber angle of a wheel for a vehicle. The adjustment bolt may be incorporated as part of an adjustment assembly that may be used to operably connect a knuckle supporting a wheel hub to a suspension strut. The adjustment bolt includes a head, a neck, a lobe or cam, and a threaded portion. The head and lobe may share a same centerline, whereas the threaded portion and the neck have different centerlines from each other and from the head and lobe. In other words, the lobe and head have a first centerline, the neck has a second centerline and the threaded portion has a third centerline. Thus, the adjustment bolt has three separate centerlines or symmetry axes. As the adjustable bolt has three different centerlines, the major diameter of the threaded portion may stay within the outer diameter of the lobe. This allows for a single size adjustable bolt to be used for multiple suspension systems with varying apertures. This may reduce the number of stock keeping units (SKUs) required to be stocked in an automobile parts store, mechanic or the like. Additionally, the multiple centerlines may also allow for a greater camber angle change, as the lobe may be created larger, having a larger offset with respect to the neck, this additional lobe size and offset with respect to the neck in turn permits a thicker washer tang, which may allow for approximately a 20% increase in adjustment angle. This is an example only. The percentage gain depends on several factors. As a general guide, the linear gain in adjustment will be about one-fourth of the difference between thread major and minor diameters (assuming the same threads are used on both bolts).

Additionally, along a first plane a major diameter of the thread portion (i.e., the diameter measured from a maximum height of each thread) is configured to be flush or effectively flush with the neck diameter and a lobe diameter. In this embodiment, the plane hits the top surface of the threads, the neck and the lob in a straight line that is parallel to a horizontal axis of the adjustment bolt. However, on a second plane the lobe diameter is not flush either with the neck or a major diameter of the threads. Thus, as viewed from a rear elevation view one side of the adjustment bolt aligns on a single plane, and on a second side the various portions of the adjustment bolt align on separate planes. As the major diameter of the threads is flush with one plane of the lobe and all the planes of the neck, the adjustment bolt may be able to be inserted into receiving apertures up to the lobe diameter. This is beneficial as fewer bolt diameter embodiments (e.g., SKUs) may need to be stored by mechanics, automobile part stores, and the like, in order to accommodate most vehicle suspension systems and also because it enhances the amount of change possible for a given receiving aperture size.

FIG. 1is an isometric view of a vehicle suspension system10including a suspension strut12operably connected via an adjustment assembly26to a knuckle assembly20. The knuckle20is operably connected to a wheel hub22. The suspension system10may be connected between a vehicle and a wheel (not shown) of the vehicle. The suspension system10may be used to steer the vehicle, as well as provide comfort for passengers within the vehicle by reducing shock from motion of the vehicle from entering into the vehicle. The suspension system10illustrated inFIG. 1is for a single wheel of a vehicle and the other half of the entire vehicle suspension is not shown. However, the other half of the suspension system may be essentially the same as the suspension system10illustrated inFIG. 1. The suspension system10includes a strut12and a spring14which are operably connected to the knuckle20via an adjustment assembly26. The knuckle20may then be operably connected to a wheel hub22via a spindle24.

The strut12and the spring14support the vehicle body, while providing damping and control for the vehicle. The strut12may consist of a generally vertical cylindrical body and the spring14wraps around the outer surface of the strut12. The adjustment assembly26operably connects to the strut12via a U-bracket18or flanges extending from the strut12. For example, as shown inFIG. 1, the U-bracket18is inserted around a lower body of the strut12, such that the strut12is surrounded on three sides. The U-bracket18receives an upper portion of the knuckle20and then an adjustment bolt16and a fastener28secure the knuckle20and U-bracket18to the strut12. In some embodiments, the U-bracket18may be replaced by flanges extending from a lower portion of the strut12(see, e.g.,FIG. 2). In these embodiments, the knuckle20may be inserted in between the two flanges, which substantially act as a U-bracket by utilizing the body of the strut12as the back portion. A wheel hub22may then connect to a spindle24extending from the knuckle20. The wheel hub22operably connects to a wheel (not shown) for the vehicle. It is contemplated that some vehicles have struts that do not include a spring. If these spring-less struts use two bolts to connect to the knuckle, then the bolt described herein is able to be utilized and performs the same or similar function. Both of adjustment bolts16and28, or either, may be camber adjustment bolts as described herein.

The adjustment assembly26may be used to vary a camber angle of the wheel hub22(and wheel) when it is connected to the knuckle20. Camber is the variance in degrees measured between true vertical and that of the measured vertical axis of the wheel assembly (when viewed from the front or the rear). For example, if the top of a wheel is farther away from the center line of the vehicle than the bottom of the wheel, the camber angle is positive. On the other hand, if the top of the wheel is closer to the centerline of the vehicle than the bottom of the wheel, the camber angle is negative. The camber angle may affect the handling qualities of a vehicle. For example, a negative camber angle may improve the grip of the tires while the vehicle is cornering. Camber angle directly affects handling and tracking of the vehicle as well as tire wear. Generally adding more negative camber will improve these characteristics, while positive settings will reduce these characteristics. If even tire wear is prioritized over handling, the adjustment assembly would be used to reduce camber closer to zero. Additionally, an excessive (e.g., too large) camber angle in any direction may increase tire wear, as well as impair handling. The adjustment assembly26alters the position of the knuckle20within the U-bracket18and with respect to the strut12, so as to alter the camber angle.

FIG. 2is an exploded view of the adjustment assembly26operably connecting the strut12to the knuckle20. The adjustment assembly26includes an adjustment bolt16, a fastener28or bolt, an adjustment washer30, and a locking nut33. The fastener28operably connects one portion of the knuckle20to the U-bracket18. The fastener28may be a bolt, screw or any other fastening device that may securely fasten the knuckle20to the U-bracket18. The fastener28may substantially prevent the knuckle20from rotating within the U-bracket18. The fastener28may be operably connected to the knuckle20and the U-bracket18with a washer, nut and the like.

The adjustment washer30may include a prong48and a tang46. The adjustment washer30is used in combination with the adjustment bolt16to adjust the camber angle for the vehicle. It should be noted that the washer30is shown as generally circularly shaped, but that the washer30or just the inner diameter thereof my be non-circularly shaped. As shown inFIG. 2, the tang46extends perpendicularly from a bottom surface of the adjustment washer30. However, the tang46may extend at angles other than perpendicular from the bottom surface of the adjustment washer30. Additionally, although the tang46is shown as being relatively planar, in some instances the tang46may be curved to relatively match the outer diameter of the neck of the adjustment bolt16, or it may be otherwise curved. The tang46may be inserted around a portion of the adjustment bolt16and placed within a receiving aperture44in the U-bracket18. The tang46helps secure the adjustment bolt16in a proper orientation within the receiving aperture44. Extending on an opposite side of the adjustment washer30is a prong48. The prong48may extend away from a main body of the washer30at a slight angle, so that when the washer30is placed against the outer surface of the U-bracket18, the prong48extends away from an outer surface of the U-bracket18. The prong48allows a user to fit the tang46within the receiving aperture44, in order to best position the adjustment bolt16and washer30within the receiving aperture44for the direction of change as desired.

FIG. 3is an isometric view of the adjustment bolt16,FIG. 4Ais a front elevation view of the adjustment bolt,FIG. 4Bis a rear elevation view of the adjustment bolt16, andFIG. 4Cis a an enlarged rear view of a portion of the adjustment bolt16illustrated inFIG. 4B. The adjustment bolt16includes a head32, a neck34, a lobe36or cam, a threaded portion38, and a transition portion40. The adjustment bolt16is configured to be inserted into the receiving apertures44on the U-bracket18and held in place via the adjustment washer30, and a locking nut33. The adjustment bolt16extends through the receiving apertures44and an adjustment aperture50(see, e.g.,FIGS. 10A and 10B) on the knuckle20. A part of each the neck34, the lobe36and the threaded portion38are retained within the adjustment aperture (such as aperture50inFIG. 10A), and then the threaded portion38extends out past the second receiving aperture44and the nut33is secured around the exposed threaded portion38. The adjustment bolt16may be steel, steel alloy (e.g.,4140steel,5140steel), or other materials with similar properties.

Referring toFIGS. 4A and 4B, the head32is configured to provide a gripping surface for a wrench, pliers, or other similar tightening or adjusting tools to allow the adjustment bolt16to be rotated within the adjustment aperture50and receiving apertures44. Thus, the head32may include a faceted or hexagonal shaped body52. The body52then expands outwards to form a plate53. The plate53, also referred to commonly as a flange, is configured to rest along an outer surface of the adjustment washer30when the adjustment bolt16is operably connected to the strut12. The head32has a length L5(FIG. 4B) measured from a bottom surface of the plate53to the front surface of the body52. The length L5is essentially the thickness of the head32and may be varied to accommodate differently sized adjustment tools, as well as differently sized receiving apertures44. In some embodiments, the head32may be replaced with a bolt head and generally circular or other shaped washer. In these instances, the plate53may be a separate washer that may be operably connected to the bolt16.

Referring generally toFIGS. 4A-4C, after the head32, the adjustment bolt16transitions into the neck34. The neck34extends eccentrically from a bottom surface of the plate53and has a smaller diameter than the plate53. The neck34includes a length L4that in some embodiments may range between approximately 11.2 mm (0.44 inches) and 12.6 mm (0.49 inches). However, it should be noted that the neck34length L4may be any dimension, as long as the lobe36may be positioned within the receiving aperture44and still be within the adjustment aperture50. Additionally, the neck34has a neck centerline56. The neck centerline56is located at a different position from the head centerline54. The neck centerline56is located at a distance C1below the head centerline54. The distance C1between the neck centerline56and the head centerline54may range between approximately 1.02 mm (0.04 inches) to approximately 1.55 mm (0.061 inches). In this manner, the center or symmetry axes of the head32and the neck34are aligned different from one another, such that the neck34may be eccentrically aligned with respect to the head32.

The lobe36extends eccentrically outwards from a bottom right surface of the neck34. The lobe36is eccentrically aligned with the neck34, such that along a right surface the head32, the neck34and the lobe36intersect at a same plane. The lobe36has a larger overall diameter than the neck34, the transition region40and the threaded portion38. The lobe36has a length L6, and the length L6may be larger than the length L4of the neck34. For example, in some embodiments the length L6may be approximately 0.55 inches and the length L4may be approximately 0.45 inches. However, in other embodiments, both the length L6and the length L4may be approximately 0.50 inches; and furthermore, the lobe length L6may be shorter than the neck34length L4.

The combination of the lobe36and the neck34has a length L3, measured from an end of the lobe36to the bottom surface of the plate53. In some embodiments, the length L3may be approximately 1 inch. However, this length L3may be any dimension as long as the length L3is approximately less than a length of the adjustment aperture50(e.g., a thickness of the knuckle20) plus the thickness of the receiving apertures44. This may help to ensure that the lobe36may not become engaged with the second receiving aperture44(on the opposite side of the U-bracket18), which could prevent the adjustment bolt16from adjusting the camber. The lobe36and the head32have the largest diameters of the adjustment bolt16. The lobe36has a lobe centerline or axis, and this centerline54is equal to the head32centerline54. In other words, the lobe36and the head32are positioned, with respect to one another, such that the same bisecting line may intersect halfway between each the head32and the lobe36. The lobe36then decreases in diameter to form the transition region40which then expands to form the threaded portion38. The transition region40extends from a right bottom surface of the lobe36, such that the transition region40is eccentrically aligned with the lobe36.

The lobe36, the neck34and the transition region40have a length L2, measured from the beginning of the threads forming the threaded portion38to the bottom surface of the plate53. The length L2may be designed such that the adjustment bolt16may extend past the U-bracket18far enough to allow the locking nut33to be secured to the adjustment bolt16. Finally, the adjustment bolt16has a length L1as measured from the bottom surface of the adjustment bolt16(i.e., the end of the threaded portion38) to the bottom surface of the plate54. This length L1may be altered to accommodate a different size strut12, U-bracket18, and/or knuckle20. The length L1may determine the percentage or portion of the adjustment bolt16that extends outwards past the second receiving aperture44within the U-bracket18.

FIG. 5Ais a right elevation view of the adjustment bolt16andFIG. 5Bis a left elevation view of the adjustment bolt16. The neck has a diameter H3, the lobe has a diameter H2, and the threaded portion38has a diameter H1. As used herein, the word diameter is contemplated to mean the major axis of an object with a circular periphery, as well as the major axis of an object that does not have a circularly periphery, such as an oval or ellipse. As can be seen inFIG. 5A, each diameter H1, H2and H3may be different. For example, in one embodiment, H1may be approximately 0.30 inches, H2may be approximately 0.470 inches, and H3may be approximately 0.351 inches. However, in other embodiments, the diameters H1, H2, H3may have different dimensions, as long as H2remains the largest, H1remains the second largest and H3is the smallest, comparatively. In one example, it should be noted that the height H3of the neck34does not have to be smaller than H1the threaded portion38; however, in most embodiments it typically may be smaller. As long as the neck34is as strong or stronger than the threaded portion38, the diameter of the neck34H3may be any size as compared with the diameter of the threaded portion H1. To enhance the potential for change to a large extent without ‘wasting’, or not efficiently using, space for neck size that cannot add strength, the neck diameter may be the same as the thread minor diameter so that strength will be roughly equivalent or the same. This allows a significantly increased practical difference in diameters H2(lobe) and H3(neck). When matched with a washer tang that is roughly equal to that difference, this arrangement may deliver the a significantly enhanced level of change.

Referring toFIGS. 4C and 5A, the varying heights or diameters H1, H2, H3of the neck34, the lobe36and the threaded portion38, as well as the eccentric alignment of each the head32, the neck34, the lobe36and the threaded portion38, contribute to the varying centerlines54,56,58for each the neck34, the lobe36and the threaded portion38. The head32and the lobe36have the same centerline54, the neck34has neck centerline56and the threaded portion38(and transition region40) has a thread centerline58. It should be noted that in some instances the head32may define a centerline that may be coaxial with any of the centerlines of the lobe36, neck34, and/or threaded portion38, or the head32may have a centerline that is offset from two or all of the other centerlines. In other words, although as shown inFIG. 4C, the head32may have the same centerline as the lobe36, in other embodiments the head32may have a fourth centerline (different from the neck34, lobe36, and threaded portion38), or the head32may have a centerline that is the same as the neck34or threaded portion38.

The adjustment bolt16thus has three centerlines54,56,58, and each centerline is different. For example, the head32and lobe36centerline54is spaced apart from the neck centerline56by a distance C1. This distance C1may range between approximately 1 mm (0.039 inches) to approximately 1.55 mm (0.061 inches) and may be determined by the desired range of camber adjustment, and/or strength of the adjustment bolt16relative to the original bolt. Additionally, the head and lobe centerline54is spaced apart from the thread centerline58by a distance C2. This distance C2is less than C1, such that the diameter H1of the threaded portion38is flush to the neck34. Note that the preceding is an example only. The benefits of a 3-axis bolt configuration as described herein is that C2would be less than C1by an amount that, when all edges stay on a ‘common plane’, the thread strength is matched to the neck strength by making the thread minor diameter match the neck diameter.

The three different centerlines54,56,58allow the adjustment bolt16to have an increased range of movement, as compared with other bolts. Prior art bolts used for adjusting the camber angle were designed so that the threaded area and the neck had the same axis or centerline. Thus, there may have been only two centerlines for the bolt. On the other hand, the adjustment bolt16has three separate centerlines54,56,58. These centerlines increase the range of movement that the adjustment bolt16may provide to the knuckle20within the U-bracket18. This is because the movement that the adjustment bolt16provides to the knuckle20may be a function of an offset between the neck34and lobe36centerlines54,56, as well as the “slop” in the receiving apertures44of the U-bracket18and/or the adjustment aperture50in the knuckle20. The ability of the adjustment bolt16to fit a large C1centerline offset distance into a given receiving aperture44and/or adjustment aperture50, allows the adjustment bolt16to provide a greater camber range for a given suspension system. This additional range may occur if the 3-axis' lobe size is enlarged to include the portion of the 2-axis' thread that was over-flush to the original lobe size.

FIG. 6is a bottom plan view of the adjustment bolt16,FIG. 7is a cross-section view of the adjustment bolt16viewed along line7-7inFIG. 5A, andFIG. 8is a cross-section view of the adjustment bolt16viewed along line8-8inFIG. 5A. The threaded portion38, the lobe36, the transition portion40and the neck34align on one side of the adjustment bolt16. In one embodiment, this may be a right side of the adjustment bolt16. As shown inFIGS. 7 and 8, the threaded portion38, the transition portion40, the lobe36, and the neck34all align on Plane A. The threaded portion38aligns on a major diameter of the threads with the outer diameter of the lobe36and neck34, in other words, the maximum diameter of the threaded portion38intersects Plane A. At least a single point on the outer diameter of each the lobe36, the neck34and the threaded portion34intersects Plane A at the same location. As best seen inFIG. 7, the threaded portion38, the transition portion40, the lobe36and the neck34are effectively flush with Plane A, and thus intersect Plane A at the same point.

As the neck34, the lobe36, the transition portion40, and a major diameter of the threaded portion38are effectively flush with one another, the adjustment bolt16may be used in smaller receiving apertures44than bolts used in the past to adjust the camber angle. As the adjustment bolt16may be used in smaller receiving apertures44, the adjustment range for the camber angle may be increased due to less “slop” within the receiving apertures44and/or the adjustment aperture50, and the number of parts or SKUs may be reduced. This is because the adjustment bolt16may fit more receiving apertures44and/or adjustment apertures50, for different vehicles and suspension systems than bolts that may have been used in the past. Reducing the number of SKUs may allow an automobile parts store or mechanic to save money by having a reduced inventory. Additionally, the degree of camber angle adjustment may be increased to 2.16 degrees in either the positive or negative direction. This angle adjustment is increased over prior art bolts by about 0.5 degrees. This additional angle adjustment may make a significant difference in certain vehicles with “non-adjustable” suspensions systems, as it provides more adjustment room to better set the camber angle. Additionally, the benefit may either be more fitments from the same SKUs (if lobe size is maintained and the threads are moved to flush), or it can be used to provide additional change if the lobe size is instead increased to ‘include’ the over-flush thread of the old design. The actual gain where the lobe size is optimized in this manner is approximately half of the thread tip-to-root height (i.e. the amount that the material outer diameter ‘grows’ when making the threads via rolling). One example of typical outer diameter gain for metric coarse threads is about 0.6 mm, which for a typical 75 mm bolt separation distance gains adjustment amount of about +/−0.46 degrees.

FIG. 9is a side elevation view of the suspension strut12connected to the knuckle20via the adjustment assembly26and illustrating the knuckle20in a positive camber angle position achieved via the adjustment assembly26and in phantom illustrating the knuckle20in a negative camber angle position. The adjustment bolt16may be used to vary the camber angle of a wheel operably connected to the knuckle20. The position of the tang46within the receiving aperture44, as well as the position of the lobe36within the adjustment aperture50determines the camber angle of the knuckle20. For example, referring toFIG. 10A, the tang46may determine whether the adjustment to the camber is in the positive or negative direction, and the position of the lobe36within the adjustment aperture50may determine the degree of angle change for the camber. Thus, the adjustment assembly26may be positioned (for instance installed, adjusted and clamped) such that the knuckle20may have a positive camber angle, a negative camber angle, or a neutral camber angle, all with respect to the vehicle (not shown).

FIG. 10Ais a cross-section view of the suspension strut12connected to the knuckle20via the adjustment assembly26illustrated inFIG. 9having a negative camber angle, viewed along line10A-10A inFIG. 9. Referring toFIGS. 9 and 10A, when the lobe36is positioned within the adjustment aperture50so that the lobe36is facing backward towards the strut12, the knuckle20may have a negative camber angle. This may be because the lobe36acts to push the knuckle20backward (away from a wheel) with respect to the U-bracket18and the strut12. Thus, when a wheel is operably connected to the knuckle20, a top portion of the wheel may be positioned toward the mid-plane of the vehicle.

FIG. 10Bis a cross-section view of the suspension strut12connected to the knuckle20via the adjustment assembly26illustrated inFIG. 9having a positive camber angle, viewed along line10B-10B inFIG. 9. Referring now toFIGS. 9 and 10B, when the lobe36of the adjustment bolt16is positioned forward towards the knuckle20, the knuckle20may have a positive camber angle. This may be because the lobe36acts to push the knuckle20forward (towards a wheel) with respect to the U-bracket18and the strut12. Thus, when a wheel is operably connected to the knuckle20, a top portion of the wheel may be positioned away from the mid-plane of the vehicle.

FIG. 11is a flow diagram illustrating a method100for adjusting the camber angle of a vehicle. The method100begins with operation102and the adjustment washer30is inserted onto the adjustment bolt16. For example, the adjustment washer30may be inserted around the threaded portion38and slid over the lobe36and around the neck34. After operation102, the method100proceeds to operation104and the tang46is aligned with the lobe36of the adjustment bolt16. For example, the tang46should be positioned on the same side of the adjustment bolt16as the side of the lobe36that is not aligned with the neck34and major diameter of the threaded portion38. In other words, the left side of the adjustment bolt16, where the lobe36extends outwards past the threaded portion38and the neck34. Once the tang46has been aligned with the lobe36, the method100proceeds to operation106. In this operation106, the adjustment bolt16is inserted into the receiving aperture44and the adjustment aperture50. The adjustment bolt16may be inserted so that the adjustment washer30is substantially flush with the U-bracket18or flange.

After the adjustment bolt16is inserted into the receiving aperture44and the adjustment aperture50, the method100proceeds to operation110. In this operation110, the user determines whether the camber angle for the suspension system10needs to be adjusted in either the positive or negative direction. If the camber angle needs to be adjusted to a positive camber angle, the method100proceeds to operation114. In operation114, the tang46is inserted into the receiving aperture44, such that it faces away from the tire or wheel of the vehicle. If, on the other hand, the camber angle needs to be adjusted to a negative camber angle, the method100proceeds to operation112. In operation112, the tang46is inserted into the receiving aperture44such that it faces towards the wheel or tire. It should be noted that if the adjustment bolt16is used in a lower receiving aperture on the U-bracket18(e.g., the receiving aperture for fastener28illustrated inFIG. 9), operations112and114may be reversed for achieving a positive or negative adjustment. In other words, if the adjustment bolt16is used in a lower receiving aperture, for positive adjustment the tang46may be inserted into the receiving aperture so that it faces towards the tire and for negative adjustment the tang46may be inserted into a lower receiving aperture so that it faces away from the tire. After operations112,114, the method100proceeds to operation115and the adjustment bolt16is rotated. As the adjustment bolt16rotates, the lobe36may be adjusted “out of phase” with the tang46, creating a change in camber.

After operation115, the method100proceeds to operation116and the adjustment bolt16is secured to the strut12and U-bracket18. This operation116may involve inserting the locking nut32onto the adjustment bolt16and then tightening the locking nut32onto the threaded portion38. However, the adjustment bolt16may be tightened to the strut12and/or the U-bracket18in other appropriate manners.

Other examples of the adjustment bolt and adjustment assembly will now be discussed.FIG. 12is a cross-section view of suspension strut connected to the knuckle via the adjustment assembly and with the adjustment bolt having an increased threaded portion height or diameter, viewed along line10A-10A inFIG. 9. With reference toFIG. 12(and as also shown inFIGS. 10A and 10B), in some instances the receiving apertures44defined in the U-bracket44of the strut12may have a larger diameter than the adjustment aperture50defined within the knuckle20. In these instances, the major diameter of the threads33of the threaded portion38of the adjustment bolt16may be increased so that the crests of the threads may engage with a bottom inner wall31of the U-bracket18defining the receiving aperture44. In general, the threads may be enlarged until they interfere with the opposite side of the strut hole from the tang46position. In other words, Thread(max)=Strut Hole−Tang Thickness (and ‘error’). Additionally, by increasing the diameter of the threaded portion38, a root diameter of the threads33(that is, the diameter or height as measured from the low point or root of each thread33), may also be larger than a diameter or height of the neck34. The diameter of the threads may be equal to the diameter of the neck.

With reference toFIG. 12, in some instances the top edge or crest of each of the threads33may be sized to substantially touch or engage the inner wall31defining the receiving aperture44within the U-bracket18of the strut12. Since clamp load is directly related to torque divided by thread diameter, the gain in clamp force comes from the higher torque that a thicker (for instance, meaning larger diameter) thread can manage prior to failing.

With continued reference toFIG. 12, as a specific example, the receiving aperture may be approximately 16.5 mm and the adjustment apertures50may be approximately 14.5 mm (although other diameter sizes are envisioned as well). Continuing with this example, the major diameter of the threads33or H1may be approximately 13 mm, a root diameter of the threads may be approximately 11.1 mm, the height H2of the lobe36may be approximately 14 mm, and a diameter or height H3of the neck34may be approximately 10.8 mm. With these values, the clamp load of the adjustment bolt16may be increased by approximately 17.4% compared to an adjustment bolt where the thread diameter has not been increased as shown inFIG. 12. It should be noted that the amount of gain or percentage increase in clamp load may depend not only the values/heights of the adjustment bolt16but also on a ratio of the receiving aperture44to adjustment aperture50ratio. Additionally, in some instances, the gain will increase more with larger thread sizes (e.g., increased height H1) as recommended maximum torque for a fastener typically increases non-linearly with thread diameter. The resulting clamp load generally increases linearly with thread size. Specifically, in some instances, torque for the adjustment bolt16may be related to the thread diameter by equation 1 (Eq. 1) below:
Torque=0.0672D3−0.5879D2−18.381  Eq. 1

As shown in Eq. 1, torque of the adjustment bolt16may increase in a non-linear fashion with an increase in the height H1of the threaded portion38. Thus, in instances of larger thread sizes, for the adjustment bolt16shown inFIG. 12, there may be a larger increase in clamping load than in the specific example discussed above.

In some instances, the adjustment ranges may be approximately the same as the adjustment bolt shown inFIGS. 10A and 10B. In other words, although the major diameter of the threads33may increase, the adjustment distance between fully negative and fully positive camber may be the same.

In yet other embodiments, the adjustment bolt16may be configured to maximize the adjustment range so as to have a greater degree of camber adjustment.FIG. 13is a cross-sectional view of the adjustment assembly viewed along line10A-10A inFIG. 9. In this example, the height H2of the lobe36may be increased to be approximately the same as the height or diameter of the adjustment aperture50defined within the knuckle20. Specifically, as shown inFIG. 13, the lobe36diameter or height H2may be approximately the same as the diameter DAof the adjustment aperture50. This may allow the lobe36, as it is rotated within the adjustment aperture50, to more directly cause the knuckle20to adjust in position. In other words, because the height H2of the lobe36may be approximately the same as the diameter DAof the adjustment aperture50, substantially every degree of rotation or movement of the lobe36may cause the knuckle to move, as the lobe36may not have space to rotate within the adjustment aperture50without engaging and moving the knuckle20. There is generally some clearance, but the clearance may be minimized in order to allow the greatest possible benefit for the change. As an example, acceptable clearances have been found to be 0.010-0.015 inches.

Typical bolts for adjusting camber in vehicles do not have a cam or lobe diameter that is approximately the same as the adjustment aperture because the threads of a bolt would be “over-flush” to the lobe. However, with reference toFIG. 4A,5A, and7, the different center lines C2and C3of the threaded portion38and the lobe36, as well as the varying heights H1and H2, the height of the lobe36can be varied without causing the major diameter of the threads33from extending past the plane A, and thus may not be “over flush” with the lobe36.

With reference toFIGS. 9 and 13, the lower fastener28may function as a pivot point for the knuckle20as it rotates due to the adjustment bolt16, and specifically as the lobe36rotates within the adjustment aperture50. In some instances, the lower fastener28may be spaced from the adjustment bolt16on the U-bracket18by a spacing distance SD(seeFIG. 9).

The spacing distance SDmay effect the range of camber adjustment for the adjustment assembly26—as SDreduces, the achievable camber range increases

In a specific example, the receiving aperture44within the U-bracket18may be approximately 16.5 mm, the adjustment aperture50or knuckle hole may be approximately 14.5 mm, the height H2of the lobe36may be approximately 14.5 mm, and the spacing distance SDbetween the adjustment bolt16and the fastener28may be approximately 75 mm. In this example, by increasing the height H2of the lobe36, the adjustment assembly26may increase the range of adjustment over conventional camber bolts by approximately 26.1%. However, this the gain percentage for camber range may vary with the spacing distance SD. That is, if all other values stay approximately the same, for smaller values of the spacing distance SDthe gain in adjustment range percentage increase may increase. This is because the closer the fastener28and thus pivot point of the knuckle20is to the adjustment bolt20, the greater the range of motion the knuckle20may have around the pivot point. Additionally, continuing the example, the adjustment range may be +/−1 to 2.5 degrees, and specifically +/−1.844 degrees. This represents an increase in adjustment range of approximately 0.382 degrees (in this example) over the equivalent 2-axis bolt in the comparison. One example of the value of Sd, for instance, is 75 mm. Other spacing values being larger or smaller are contemplated. That is, the camber change that may be implemented by the adjustment bolt16may be increased to include 1.844 degrees of additional range of movement in either the positive or negative orientation.

In some instances, the adjustment bolt16ofFIG. 12may be combined with the adjustment bolt16ofFIG. 13.FIG. 14is a cross-sectional view of the adjustment assembly viewed along line10A-10A inFIG. 9including another example of the adjustment bolt. InFIG. 14, the adjustment bolt16may include a lobe height H2or diameter that may be substantially the same as the adjustment aperture50and the major diameter of the threads33may be selected so that at least one portion of the threads33engages a portion of the inner wall31of the U-bracket18. In the embodiment illustrated inFIG. 14, the clamp load may be optimized based on an optimized adjustment range. and the lobe36height H2is increased to better effect motion of the knuckle20, providing an increased adjustment range and an increased clamp load. This is different than the embodiment inFIG. 13, where there is a gap between the crest of the threads33and the bottom inner wall31of the receiving aperture44. Accordingly, as compared to the adjustments bolt16ofFIG. 13, the adjustment bolt16illustrated inFIG. 14will have an increased clamp load for the assembly29.

In a specific example, with reference toFIG. 14, the receiving aperture44may be approximately 16.5 mm, the adjustment aperture50may have a diameter of approximately 14.5 mm, the lobe36may have a diameter of height H2or approximately 14.5 mm, the neck36may have a diameter or height H3of approximately 10.8 mm, and the threads33may have a root diameter of approximately 11.1 mm. In this example, the clamp load may be increased over conventional bolts by approximately 17.4% and the camber adjustment range may be increased by approximately 26.1%.

The increase in clamp load and the increase in adjustment range as shown inFIG. 14may be increased in the adjustment bolt16over 2-axis conventional camber adjusting bolts.FIG. 15is a graph illustrating adjustment range of the improvement of the adjustment bolt and clamp load values based on an assembly geometry or offset. The assembly geometry or offset may be varied by varying the offset between the neck centerline C1compared to the lobe centerline C3, a thickness of the tang48of the adjustment washer30, and/or variations in the diameters between the adjustment aperture50and the receiving aperture44. Where the strut/knuckle hole sizing differs, further optimization of the tang thickness may be done to gain additional change (if the ratio becomes bigger than used in the example herein).

With reference toFIG. 15, the x-ordinate represents the Cam Geometry/Offset (i.e. the tang46thickness). The Y-axis Y1on the left side of the graph represents the change in change in adjustment range, and the Y-axis Y2on the right side of the graph represents the change in clamp load. The lines CL2and AR2may represent the values for a conventional bolt having two centerlines or axes for adjusting clamp load and adjustment range, respectively. The lines CL3and AR3may represent the values for an adjustment bolt having three uncommon centerlines or axes, such as those described herein. As can be seen inFIG. 15, the adjustment bolt having three axes provides increased values of both adjustment range and clamp load, as compared with conventional bolts. In some embodiments, the adjustment bolt16may have an increased gain of approximately 20% to 30% as compared with conventional camber adjusting bolts.

Referring still toFIG. 15, the comparison of CL3and CL2were made with the thread and lobe diameters being equivalent between the two axes bolt and three axes bolts. Delta A represents the difference between the clamping load for the two bolts at points along the two lines. Delta B represents the difference between the clamp load for the two bolts at points along the two lines. In one example, the comparison lines CL2and CL3, as well as AR2and AR3are parallel over the range of tang thicknesses.

The additional change Delta A equals the distance between the first and third axes when the tang and lobe sizes are equal between the two axes bolt and the three axes bolt. This Delta A value converts to degrees when implemented in the strut adjustment system26. The additional claim load Delta B is the difference between the tang and lobe thicknesses. For the three axis bolt the thread minor diameter can equal the neck size and for the two axes bolt the major diameter of the thread must equal the neck diameter.

Additionally, the thickness of the adjustment washer30may also drive the height H1of the threaded portion38that may be required for the adjustment bolt16to fit through the receiving apertures44within the U-bracket18. In these instances, because the height H1of the neck34can be increased for the same size apertures44,50, the strength of the neck34may be increased for the same size assemblies. It should be noted that in some instances, the receiving aperture44within the U-bracket18may be relatively round, and the tang46may be relatively rectangular or non-rounded. In these instances, the effective thickness of the tang46may include some additional dimensions to account for the rectangular or square shape of the tang46interacting with the rounded shape of the receiving aperture44.