This invention was not made as part of a federally sponsored research or development project.
The present invention relates to sports equipment; particularly, to a high volume aerodynamic golf club head.
Modern high volume golf club heads, namely drivers, are being designed with little, if any, attention paid to the aerodynamics of the golf club head. This stems in large part from the fact that in the past the aerodynamics of golf club heads were studied and it was found that the aerodynamics of the club head had only minimal impact on the performance of the golf club.
The drivers of today have club head volumes that are often double the volume of the most advanced club heads from just a decade ago. In fact, virtually all modern drivers have club head volumes of at least 400 cc, with a majority having volumes right at the present USGA mandated limit of 460 cc. Still, golf club designers pay little attention to the aerodynamics of these large golf clubs; often instead focusing solely on increasing the club head's resistance to twisting during off-center shots.
The modern race to design golf club heads that greatly resist twisting, meaning that the club heads have large moments of inertia, has led to club heads having very long front-to-back dimensions. The front-to-back dimension of a golf club head, often annotated the FB dimension, is measured from the leading edge of the club face to the furthest back portion of the club head. Currently, in addition to the USGA limit on the club head volume, the USGA limits the front-to-back dimension (FB) to 5 inches and the moment of inertia about a vertical axis passing through the club head's center of gravity (CG), referred to as MOIy, to 5900 g*cm2. One of skill in the art will know the meaning of “center of gravity,” referred to herein as CG, from an entry level course on mechanics. With respect to wood-type golf clubs, which are generally hollow and/or having non-uniform density, the CG is often thought of as the intersection of all the balance points of the club head. In other words, if you balance the head on the face and then on the sole, the intersection of the two imaginary lines passing straight through the balance points would define the point referred to as the CG.
Until just recently the majority of drivers had what is commonly referred to as a “traditional shape” and a 460 cc club head volume. These large volume traditional shape drivers had front-to-back dimensions (FB) of approximately 4.0 inches to 4.3 inches, generally achieving an MOIy in the range of 4000-4600 g*cm2. As golf club designers strove to increase MOIy as much as possible, the FB dimension of drivers started entering the range of 4.3 inches to 5.0 inches. The graph of
While increasing the FB dimension to achieve higher MOIy values is logical, significant adverse effects have been observed in these large FB dimension clubs. One significant adverse effect is a dramatic reduction in club head speed, which appears to have gone unnoticed by many in the industry. The graph of
This significant decrease in club head speed is the result of the increase in aerodynamic drag forces associated with large FB dimension golf club heads. Data obtained during extensive wind tunnel testing shows a strong correlation between club head FB dimension and the aerodynamic drag measured at several critical orientations. First, orientation one is identified in
Secondly, orientation two is identified in
Thirdly, orientation three is identified in
Now referring back to orientation one, namely the orientation identified in
Still referencing
The results are much the same in orientation two, namely the orientation identified in
Again, the results are much the same in orientation three, namely the orientation identified in
Further, the graph of
The drop in club head speed just described has a significant impact on the speed at which the golf ball leaves the club face after impact and thus the distance that the golf ball travels. In fact, for a club head speed of approximately 100 mph, each 1 mph reduction in club head speed results in approximately a 1% loss in distance. The present golf club head has identified these relationships, the reason for the drop in club head speed associated with long FB dimension clubs, and several ways to reduce the aerodynamic drag force of golf club heads.
The claimed aerodynamic golf club head has recognized that the poor aerodynamic performance of large FB dimension drivers is not due solely to the large FB dimension; rather, in an effort to create large FB dimension drivers with a high MOIy value and low center of gravity (CG) dimension, golf club designers have generally created clubs that have very poor aerodynamic shaping. Several problems are the significantly flat surfaces on the body, the lack of proper shaping to account for airflow reattachment in the crown area trailing the face, and the lack of proper trailing edge design. In addition, current large FB dimension driver designs have ignored, or even tried to maximize in some cases, the frontal cross sectional area of the golf club head which increases the aerodynamic drag force.
The present aerodynamic golf club head solves these issues and results in a high volume aerodynamic golf club head having a relatively large FB dimension with beneficial moment of inertia values, while also obtaining superior aerodynamic properties unseen by other large volume, large FB dimension, high MOI golf club heads. The golf club head obtains superior aerodynamic performance through the use of unique club head shapes defined by numerous variables including, but not limited to, a crown apex located an apex height above a ground plane, and three distinct radii that improve the aerodynamic performance.
The club head has a crown section having a portion between the crown apex and a front of the club head with an apex-to-front radius of curvature that is less than 3 inches. Likewise, a portion of the crown section between the crown apex and a back of the club head has an apex-to-rear radius of curvature that is less than 3.75 inches. Lastly, a portion of the crown section has a heel-to-toe radius of curvature at the crown apex in a direction parallel to a vertical plane created by a shaft axis that is less than 4 inches. Such small radii of curvature herein have traditionally been avoided in the design of high volume golf club heads, especially in the design of high volume golf club heads having FB dimensions of 4.4 inches and greater. However, these tight radii produce a bulbous crown section that facilitates airflow reattachment as close to a club head face as possible, thereby resulting in reduced aerodynamic drag forces and producing higher club head speeds.
Without limiting the scope of the present aerodynamic golf club head as claimed below and referring now to the drawings and figures:
These drawings are provided to assist in the understanding of the exemplary embodiments of the high volume aerodynamic golf club head as described in more detail below and should not be construed as unduly limiting the present golf club head. In particular, the relative spacing, positioning, sizing and dimensions of the various elements illustrated in the drawings are not drawn to scale and may have been exaggerated, reduced or otherwise modified for the purpose of improved clarity. Those of ordinary skill in the art will also appreciate that a range of alternative configurations have been omitted simply to improve the clarity and reduce the number of drawings.
The claimed high volume aerodynamic golf club head (100) enables a significant advance in the state of the art. The preferred embodiments of the club head (100) accomplish this by new and novel arrangements of elements and methods that are configured in unique and novel ways and which demonstrate previously unavailable but preferred and desirable capabilities. The description set forth below in connection with the drawings is intended merely as a description of the presently preferred embodiments of the club head (100), and is not intended to represent the only form in which the club head (100) may be constructed or utilized. The description sets forth the designs, functions, means, and methods of implementing the club head (100) in connection with the illustrated embodiments. It is to be understood, however, that the same or equivalent functions and features may be accomplished by different embodiments that are also intended to be encompassed within the spirit and scope of the club head (100).
The present high volume aerodynamic golf club head (100) has recognized that the poor aerodynamic performance of large FB dimension drivers is not due solely to the large FB dimension; rather, in an effort to create large FB dimension drivers with a high MOIy value and low center of gravity (CG) dimension, golf club designers have generally created clubs that have very poor aerodynamic shaping. The main problems are the significantly flat surfaces on the body, the lack of proper shaping to account for airflow reattachment in the crown area trailing the face, and the lack of proper trailing edge design. In addition, current large FB dimension driver designs have ignored, or even tried to maximize in some cases, the frontal cross sectional area of the golf club head which increases the aerodynamic drag force. The present aerodynamic golf club head (100) solves these issues and results in a high volume aerodynamic golf club head (100) having a large FB dimension and a high MOIy.
The present high volume aerodynamic golf club head (100) has a volume of at least 400 cc. It is characterized by a face-on normalized aerodynamic drag force of less than 1.5 lbf when exposed to a 100 mph wind parallel to the ground plane (GP) when the high volume aerodynamic golf club head (100) is positioned in a design orientation and the wind is oriented at the front (112) of the high volume aerodynamic golf club head (100), as previously described with respect to
With general reference to
The relatively large FB dimension of the present high volume aerodynamic golf club head (100) aids in obtaining beneficial moment of inertia values while also obtaining superior aerodynamic properties unseen by other large volume, large FB dimension, high MOI golf club heads. Specifically, an embodiment of the high volume aerodynamic golf club head (100) obtains a first moment of inertia (MOIy) about a vertical axis through a center of gravity (CG) of the golf club head (100), illustrated in
The golf club head (100) obtains superior aerodynamic performance through the use of unique club head shapes. Referring now to
The center of the face (200) shall be determined in accordance with the USGA “Procedure for Measuring the Flexibility of a Golf Clubhead,” Revision 2.0, Mar. 25, 2005, which is incorporated herein by reference. This USGA procedure identifies a process for determining the impact location on the face of a golf club that is to be tested, also referred therein as the face center. The USGA procedure utilizes a template that is placed on the face of the golf club to determine the face center.
Secondly, a portion of the crown section (400) between the crown apex (410) and the back (114) of the hollow body (110) has an apex-to-rear radius of curvature (Ra-r) that is less than 3.75 inches. The apex-to-rear radius of curvature (Ra-r) is also measured in a vertical plane that is perpendicular to a vertical plane passing through the shaft axis (SA), and the apex-to-rear radius of curvature (Ra-r) is further measured at the point on the crown section (400) between the crown apex (410) and the back (114) that has the smallest the radius of curvature. In one particular embodiment, at least fifty percent of the vertical plane cross sections taken perpendicular to a vertical plane passing through the shaft axis (SA), which intersect a portion of the face top edge (210), are characterized by an apex-to-rear radius of curvature (Ra-r) of less than 3.75 inches. In still a further embodiment, at least ninety percent of the vertical plane cross sections taken perpendicular to a vertical plane passing through the shaft axis (SA), which intersect a portion of the face top edge (210), are characterized by an apex-to-rear radius of curvature (Ra-r) of less than 3.75 inches. In yet another embodiment, one hundred percent of the vertical plane cross sections taken perpendicular to a vertical plane passing through the shaft axis (SA), which intersect a portion of the face top edge (210) between the center of the face (200) and the toeward most point on the face (200), are characterized by an apex-to-rear radius of curvature (Ra-r) of less than 3.75 inches.
Lastly, as seen in
Such small radii of curvature exhibited in the embodiments described herein have traditionally been avoided in the design of high volume golf club heads, especially in the design of high volume golf club heads having FB dimensions of 4.4 inches and greater. However, it is these tight radii produce a bulbous crown section (400) that facilitates airflow reattachment as close to the face (200) as possible, thereby resulting in reduced aerodynamic drag forces and facilitating higher club head speeds.
Conventional high volume large MOIy golf club heads having large FB dimensions, such as those seen in USPN D544939 and USPN D543600, have relatively flat crown sections that often never extend above the face. While these designs appear as though they should cut through the air, the opposite is often true with such shapes achieving poor airflow reattachment characteristics and increased aerodynamic drag forces. The present club head (100) has recognized the significance of proper club head shaping to account for rapid airflow reattachment in the crown section (400) trailing the face (200), which is quite the opposite of the flat steeply sloped crown sections of many prior art large FB dimension club heads.
With reference now to
One of many significant advances of this embodiment of the present club head (100) is the design of an apex ratio that encourages airflow reattachment on the crown section (400) of the golf club head (100) as close to the face (200) as possible. In other words, the sooner that airflow reattachment is achieved, the better the aerodynamic performance and the smaller the aerodynamic drag force. The apex ratio is the ratio of apex height (AH) to the maximum top edge height (TEH). As previously explained, in many large FB dimension golf club heads the apex height (AH) is no more than the top edge height (TEH). In this embodiment, the apex ratio is at least 1.13, thereby encouraging airflow reattachment as soon as possible.
Still further, this embodiment of the club head (100) has a frontal cross sectional area that is less than 11 square inches. The frontal cross sectional area is the single plane area measured in a vertical plane bounded by the outline of the golf club head (100) when it is resting on the ground plane (GP) at the design lie angle and viewed from directly in front of the face (200). The frontal cross sectional area is illustrated by the cross-hatched area of
In a further embodiment, a second aerodynamic drag force is introduced, namely the 30 degree offset aerodynamic drag force, as previously explained with reference to
Yet another embodiment introduces a third aerodynamic drag force, namely the heel normalized aerodynamic drag force, as previously explained with reference to
A still further embodiment has recognized that having the apex-to-front radius of curvature (Ra-f) at least 25% less than the apex-to-rear radius of curvature (Ra-r) produces a particularly aerodynamic golf club head (100) further assisting in airflow reattachment and preferred airflow attachment over the crown section (400). Yet another embodiment further encourages quick airflow reattachment by incorporating an apex ratio of the apex height (AH) to the maximum top edge height (TEH) that is at least 1.2. This concept is taken even further in yet another embodiment in which the apex ratio of the apex height (AH) to the maximum top edge height (TEH) is at least 1.25. Again, these large apex ratios produce a bulbous crown section (400) that facilitates airflow reattachment as close to the face (200) as possible, thereby resulting in reduced aerodynamic drag forces and resulting in higher club head speeds.
Reducing aerodynamic drag by encouraging airflow reattachment, or conversely discouraging extended lengths of airflow separation, may be further obtained in yet another embodiment in which the apex-to-front radius of curvature (Ra-f) is less than the apex-to-rear radius of curvature (Ra-r), and the apex-to-rear radius of curvature (Ra-r) is less than the heel-to-toe radius of curvature (Rh-t). Such a shape is contrary to conventional high volume, long FB dimension golf club heads, yet produces a particularly aerodynamic shape.
Taking this embodiment a step further in another embodiment, a high volume aerodynamic golf club head (100) having the apex-to-front radius of curvature (Ra-f) less than 2.85 inches and the heel-to-toe radius of curvature (Rh-t) less than 3.85 inches produces a reduced face-on aerodynamic drag force. Another embodiment focuses on the playability of the high volume aerodynamic golf club head (100) by having a maximum top edge height (TEH) that is at least 2 inches, thereby ensuring that the face area is not reduced to an unforgiving level. Even further, another embodiment incorporates a maximum top edge height (TEH) that is at least 2.15 inches, further instilling confidence in the golfer that they are not swinging a golf club head (100) with a small striking face (200).
The foregoing embodiments may be utilized having even larger FB dimensions. For example, the previously described aerodynamic attributes may be incorporated into an embodiment having a front-to-back dimension (FB) that is at least 4.6 inches, or even further a front-to-back dimension (FB) that is at least 4.75 inches. These embodiments allow the high volume aerodynamic golf club head (100) to obtain even higher MOIy values without reducing club head speed due to excessive aerodynamic drag forces.
Yet a further embodiment balances all of the radii of curvature requirements to obtain a high volume aerodynamic golf club head (100) while minimizing the risk of an unnatural appearing golf club head by ensuring that less than 10% of the club head volume is above the elevation of the maximum top edge height (TEH). A further embodiment accomplishes the goals herein with a golf club head (100) having between 5% to 10% of the club head volume located above the elevation of the maximum top edge height (TEH). This range achieves the desired crown apex (410) and radii of curvature to ensure desirable aerodynamic drag while maintaining an aesthetically pleasing look of the golf club head (100).
The location of the crown apex (410) is dictated to a degree by the apex-to-front radius of curvature (Ra-f); however, yet a further embodiment identifies that the crown apex (410) should be behind the forwardmost point on the face (200) a distance that is a crown apex setback dimension (412), seen in
Additionally, the heel-to-toe location of the crown apex (410) also plays a significant role in the aerodynamic drag force. The location of the crown apex (410) in the heel-to-toe direction is identified by the crown apex ht dimension (414), as seen in
The present high volume aerodynamic golf club head (100) has a club head volume of at least 400 cc. Further embodiments incorporate the various features of the above described embodiments and increase the club head volume to at least 440 cc, or even further to the current USGA limit of 460 cc. However, one skilled in the art will appreciate that the specified radii and aerodynamic drag requirements are not limited to these club head sizes and apply to even larger club head volumes. Likewise, a heel-to-toe (HT) dimension of the present club head (100), as seen in
Now, turning our attention to another invention that is not limited to a “high volume” golf club head; in fact, the benefits of the present invention may be applied to drivers, fairway woods, and hybrid type golf club heads having volumes as small as 75 cc and as large as allowed by the USGA at any point in time, currently 460 cc. With reference to
As noted in the prior disclosure with reference to
As previously mentioned, the trip step (500) is located between the crown apex (410) and the back (114); as such, several elements are utilized to identify the location of the trip step (500). As seen in
The trip step (500) enables significant reduction in the aerodynamic drag force exerted on the aerodynamic golf club head (100) of the present invention. For instance,
The graph of
Interestingly, the final entry in the graph legend of
The present invention has uniquely identified the window of opportunity to apply a trip step (500) and obtain reduced aerodynamic drag force. The trip step (500) must be located behind the crown apex (410). Further, specific locations, shapes, and edge profiles provide preferred aerodynamic results. The present invention provides an aerodynamic golf club head (100) has a face-on aerodynamic drag force of less than 1.0 lbf when exposed to a 90 mph wind parallel to the ground plane (GP) when the aerodynamic golf club head (100) is positioned in a design orientation and the wind is oriented at the front (112) of the aerodynamic golf club head (100). In a further embodiment the aerodynamic drag force is less than 1.0 lbf throughout the orientations from 0 degrees up to 110 degrees. In yet another embodiment the aerodynamic drag force is 0.85 lbf or less throughout the orientation of 10 degrees up to 90 degrees. Still further, the two inch trip step offset (514) of
At a higher wind speed of 110 mph, seen in
The trip step thickness (540), seen in
In yet another embodiment the lineal length of the trip step (500) is greater than seventy-five percent of the heel-to-toe dimension (HT). This length of trip step (500) causes the laminar to turbulent transition over enough of the crown section (400) to achieve the desired reduction in aerodynamic drag force. Further, in another embodiment the trip step (500) is continuous and uninterrupted. An even further embodiment with a bulbous crown section (400) incorporates a trip step (500) in which the lineal length of the trip step (500) is greater than the heel-to-toe dimension (HT). However, even in this embodiment the trip step (500) is limited to the crown section (400).
The leading edge profile (512) of the trip step (500) may be virtually any configuration. Further, the trip step leading edge (510) does not have to be parallel to the trip step trailing edge (520), thus the trip step width (530) may be variable. In one particular embodiment the leading edge profile (512) includes a sawtooth pattern to further assist in the transition from laminar to turbulent flow. The sawtooth leading edge profile (512) seen in
Further, a trip step width (530) of ¼ inch or less produces the desired air flow transition. Still further, one embodiment has found that a trip step width (530) of less than the apex-to-leading edge offset (516) produces preferred transition characteristics. The trip step width (530) does not have to be uniform across the entire length of the trip step (500).
Yet another embodiment has an apex-to-leading edge offset (516), seen best in
While the trip step (500) of
The introduction of the multi-sectional trip step (570) affords numerous embodiments of the present invention. One particular embodiment simply incorporates a design in which aerodynamic drag force is reduced by incorporating a trip step (500) that has an apex-to-heel LE offset (517) that is greater than the apex-to-leading edge offset (516), and an apex-to-toe LE offset (518) that is greater than the apex-to-leading edge offset (516), which is true of the embodiment seen in
Another embodiment of the multi-sectional trip step (570) variation incorporates a face oriented trip step section (585) that is parallel to the vertical plane passing through the shaft axis (SA). Thus, this embodiment incorporates a section (585) that is essentially parallel to the face (200), and a section that is not. Such embodiments capitalize on the fact that during a golf swing air does not merely pass over the crown section (400) from the face (200) to the back (114) in a straight manner. In fact, a large portion of the swing is occupied with the golf club head (100) slicing through the air being led by the hosel (120), or the heel (116) side of the club. That said, reducing the face-on aerodynamic drag force, also referred to as the “Air Flow-90°” orientation of
Yet another embodiment, seen in
Another embodiment directed to the achieving a preferential balance of reducing the aerodynamic drag force in multiple orientations incorporates a curved trip step (500), as seen in
Yet another embodiment places the trip step (500) at, or slightly in front of, the natural location of air flow separation on the club head without the trip step (500). Thus, wind tunnel testing can be performed to visually illustrate the natural air flow separation pattern on the crown of a particular golf club head design. Then, a curved trip step (500) may be applied to a portion of the crown section (400) at the natural air flow separation curve, or slightly forward of the natural air flow separation curve in a direction toward the face (200). Thus, in this embodiment, seen in
The curved trip step (500) does not need to be one continuous smooth curve. In fact, the curved trip step (500) may be a compound curve. Further, as previously mentioned, the curved trip step (500) is not required to extend toward the heel (116) of the golf club because the disruption in the air flow pattern caused by the hosel results in turbulent air flow near the heel (116), and thus it is unlikely a reduction in aerodynamic drag force is achieved by extending the curved trip step (500) all the way to the heel (116). However, the aesthetically pleasing embodiment of
All of the previously described aerodynamic characteristics with respect to the crown section (400) apply equally to the sole section (300) of the high volume aerodynamic golf club head (100). In other words, one skilled in the art will appreciate that just like the crown section (400) has a crown apex (410), the sole section (300) may have a sole apex. Likewise, the three radii of the crown section (400) may just as easily be three radii of the sole section (300). Thus, all of the embodiments described herein with respect to the crown section (400) are incorporated by reference with respect to the sole section (300).
The various parts of the golf club head (100) may be made from any suitable or desired materials without departing from the claimed club head (100), including conventional metallic and nonmetallic materials known and used in the art, such as steel (including stainless steel), titanium alloys, magnesium alloys, aluminum alloys, carbon fiber composite materials, glass fiber composite materials, carbon pre-preg materials, polymeric materials, and the like. The various sections of the club head (100) may be produced in any suitable or desired manner without departing from the claimed club head (100), including in conventional manners known and used in the art, such as by casting, forging, molding (e.g., injection or blow molding), etc. The various sections may be held together as a unitary structure in any suitable or desired manner, including in conventional manners known and used in the art, such as using mechanical connectors, adhesives, cements, welding, brazing, soldering, bonding, and other known material joining techniques. Additionally, the various sections of the golf club head (100) may be constructed from one or more individual pieces, optionally pieces made from different materials having different densities, without departing from the claimed club head (100).
Numerous alterations, modifications, and variations of the preferred embodiments disclosed herein will be apparent to those skilled in the art and they are all anticipated and contemplated to be within the spirit and scope of the instant club head. For example, although specific embodiments have been described in detail, those with skill in the art will understand that the preceding embodiments and variations can be modified to incorporate various types of substitute and or additional or alternative materials, relative arrangement of elements, and dimensional configurations. Accordingly, even though only few variations of the present club head are described herein, it is to be understood that the practice of such additional modifications and variations and the equivalents thereof, are within the spirit and scope of the club head as defined in the following claims. The corresponding structures, materials, acts, and equivalents of all means or step plus function elements in the claims below are intended to include any structure, material, or acts for performing the functions in combination with other claimed elements as specifically claimed.
This application is a continuation of U.S. nonprovisional application Ser. No. 17/485,977, filed on Sep. 27, 2021, which is a continuation of U.S. nonprovisional application Ser. No. 16/707,774, filed on Dec. 9, 2019, now U.S. Pat. No. 11,130,026, which is a continuation of U.S. nonprovisional application Ser. No. 16/105,001, filed on Aug. 20, 2018, now U.S. Pat. No. 10,500,451, which is a continuation of U.S. nonprovisional application Ser. No. 15/603,605, filed on May 24, 2017, now U.S. patent Ser. No. 10/052,531, which is a continuation of U.S. nonprovisional application Ser. No. 15/012,880, filed on Feb. 2, 2016, now U.S. Pat. No. 9,682,294, which is a continuation of U.S. nonprovisional application Ser. No. 14/260,328, filed on Apr. 24, 2014, now U.S. Pat. No. 9,278,266, which is a continuation of U.S. nonprovisional application Ser. No. 14/069,503, now U.S. Pat. No. 8,734,269, filed on Nov. 1, 2013, which is a continuation of U.S. nonprovisional application Ser. No. 13/969,670, now U.S. Pat. No. 8,602,909, filed on Aug. 19, 2013, which is a continuation of U.S. nonprovisional application Ser. No. 13/670,703, now U.S. Pat. No. 8,550,936, filed on Nov. 7, 2012, which is a continuation of U.S. nonprovisional application Ser. No. 13/304,863, now abandoned, filed on Nov. 28, 2011, which is a continuation of U.S. nonprovisional application Ser. No. 12/367,839, now U.S. Pat. No. 8,083,609, filed on Feb. 9, 2009, which claims the benefit of U.S. provisional patent application Ser. No. 61/080,892, filed on Jul. 15, 2008, and U.S. provisional patent application Ser. No. 61/101,919, filed on Oct. 1, 2008, all of which are incorporated by reference as if completely written herein.
Number | Date | Country | |
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61080892 | Jul 2008 | US | |
61101919 | Oct 2008 | US |
Number | Date | Country | |
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Parent | 17485977 | Sep 2021 | US |
Child | 18207276 | US | |
Parent | 16707774 | Dec 2019 | US |
Child | 17485977 | US | |
Parent | 16105001 | Aug 2018 | US |
Child | 16707774 | US | |
Parent | 15603605 | May 2017 | US |
Child | 16105001 | US | |
Parent | 15012880 | Feb 2016 | US |
Child | 15603605 | US | |
Parent | 14260328 | Apr 2014 | US |
Child | 15012880 | US | |
Parent | 14069503 | Nov 2013 | US |
Child | 14260328 | US | |
Parent | 13969670 | Aug 2013 | US |
Child | 14069503 | US | |
Parent | 13670703 | Nov 2012 | US |
Child | 13969670 | US | |
Parent | 13304863 | Nov 2011 | US |
Child | 13670703 | US | |
Parent | 12367839 | Feb 2009 | US |
Child | 13304863 | US |