Patent Grant
8307774
1. Field of the Invention
This invention generally relates to a rowing boat footrest assembly. More specifically, the present invention relates to a rowing boat footrest assembly which includes a rudder control function.
2. Background Information
Traditionally, the footrest in a rowing boat is an angled surface upon which a rower can brace his or her feet to provide increased power during the rowing process. Recently, footrests have been provided with simple shoe retaining straps or mechanisms that hold a rower's shoe against the surface of the footrest. Typically, the footrest cannot move during the rowing back and forth stroke. However, the footrest is often adjustable to accommodate different sizes of rowers. In some instances, the location of the entire footrest is adjustable in the longitudinal direction of the rowing boat. Also, in some cases, the angle of the footrest is adjustable with respect to the rowing boat.
In some cases, rowing boats are provided with a rudder to steer the rowing boat in the water. Since a rower is typically using both hands for rowing, it is difficult for the rower to operate the rudder while rowing. To avoid this problem, it has been proposed to provide a foot operated steering apparatus that allows the rower to control a rudder of the rowing boat while rowing. For example, one proposed foot operated steering apparatus is disclosed in U.S. Pat. No. 231,017,which issued to Michael F. Davis.
In view of the above, it will be apparent to those skilled in the art from this disclosure that there exists a need for an improved rowing boat footrest assembly that includes a rudder control function. This invention addresses this need in the art as well as other needs, which will become apparent to those skilled in the art from this disclosure.
One aspect is to provide a rowing boat footrest assembly that includes a rudder control function.
In view of the state of the known technology, a rowing boat footrest assembly is proposed that basically comprises a base, a foot-rudder control member, a footrest member and a positioning structure. The foot-rudder control member pivotally coupled to the base. The foot-rudder control member includes a rudder control attachment. The footrest member is supported on the foot-rudder control member. The footrest member includes a shoe attachment. The positioning structure is operatively coupled between the base and the foot-rudder control member. The positioning structure includes a contact member and a setting member. The contact member is movably provided to one of the base and the foot-rudder control member. The contact member is biased into contact with the other of the base and the foot-rudder control member. The setting member is adjustably arranged to change an urging force on the contact member.
These and other objects, features, aspects and advantages of the present invention will become apparent to those skilled in the art from the following detailed description, which, taken in conjunction with the annexed drawings, discloses preferred embodiments.
Referring now to the attached drawings which form a part of this original disclosure:
Selected embodiments will now be explained with reference to the drawings. It will be apparent to those skilled in the art from this disclosure that the following descriptions of the embodiments are provided for illustration only and not for the purpose of limiting the invention as defined by the appended claims and their equivalents.
Referring initially to
The stationary boat mounting structure 14 can be a relatively conventional structure, as shown, that is rigidly fixed or rigidly supported to an interior portion or gunwale portion of the hull of the rowing boat 10. The hull of the rowing boat 10 can have any of a variety of conventional shapes and configurations depending upon whether the type of boat. More specifically, the size and shape of the hull of the rowing boat 10 can have any size and shape that can accommodate the rowing boat footrest assembly 12. It should be apparent to those skilled in the rowing boat field from the drawings and the description herein that the stationary boat mounting structure 14 can be a structure integrally formed with the hull of the rowing boat 10 or rigidly fixed to the hull of the rowing boat 10.
In this illustrated embodiment, the stationary boat mounting structure 14 includes a pair of side rails 14a and a center rail 14b. In particular, the side rails 14a are fixedly arranged parallel to one another along the sides of the hull of the boat 10, with the center rail 14b being arranged parallel to the side rails 14a along a center of the floor of the hull of the boat 10. In this illustrated embodiment, the side rails 14a are equidistant from the center rail 14b.
The sculling seat structure 16 includes a seat 16a and a pair of parallel rails 16b. One of the rails 16b is disposed on each of the lateral sides of the boat 10. The rails 16b slidably support the seat 16a to slide smoothly in a fore and aft (longitudinal) direction relative to the hull of the rowing boat 10. The seat 16a includes bearing portions such as rolling wheels or bushing surfaces that allow the seat 16a to slide along rails 16b. The sculling seat structure 16 can be a relatively conventional structure, as shown, and thus, the sculling seat structure 16 will not be discussed in detail herein.
As best seen in
As seen in
As seen in
As seen in
In this illustrated embodiment, a first pivot structure 44 is provided between the base 30 and the foot-rudder control member 32 so that the first pivot structure 44 pivotally supports the foot-rudder control member 32 on the base 30. The first pivot structure 44 defines a first pivot axis P1 of pivotal movement between the base 30 and the foot-rudder control member 32. In other words, the foot-rudder control member 32 pivots relative to the base 30 along an arc having its center located at the first pivot axis P1. Thus, the foot-rudder control member 32 pivots about the first pivot axis P1 relative to the base 30.
In this illustrated embodiment, when the foot-rudder control member 32 is pivoted about the first pivot axis P1 to the right relative to the base 30, the rudder 22 is turned the left (counterclockwise as viewed from above). On the other hand, when the foot-rudder control member 32 is pivoted about the first pivot axis P1 to the left relative to the base 30, the rudder 22 is turned the right (clockwise as viewed from above). Of course, the connection between the rudder 22 and the foot-rudder control member 32 can be modified so that the rudder 22 is turns in the same direction of the movement of the foot-rudder control member 32 if needed and/or desired.
Also in this illustrated embodiment, a second pivot structure 46 is provided between the foot-rudder control member 32 and the footrest member 34 so that second pivot structure 46 pivotally supports the footrest member 34 on the foot-rudder control member 32 to change a shoe inclination of the footrest member 34 with respect to the foot-rudder control member 32. The second pivot structure 46 defining a second pivot axis P2 of pivotal movement between the footrest member 34 and the foot-rudder control member 32. In other words, the footrest member 34 pivots relative to the foot-rudder control member 32 along an arc having its center located at the second pivot axis P2. Thus, the footrest member 34 pivots about the second pivot axis P2 relative to the foot-rudder control member 32.
In this illustrated embodiment, the first pivot structure 44 is arranged with respect to the second pivot structure 46 such that the second pivot axis P2 is adjacent the first pivot axis P1 with respect to in a longitudinal direction (i.e., along axis L) of a rower's shoe disposed on the foot rest 34 in the normal rowing position. The second pivot axis P2 is not parallel to the first pivot axis P1. In particular, in this illustrated embodiment, the first and second pivot axes P1 and P2 are substantially perpendicular (i.e., ±5° from 90°). The first pivot structure 44 is arranged with respect to the second pivot structure 46 such that the first pivot axis P1 is disposed within twenty millimeters of the second pivot axis P2 with respect to the longitudinal direction (i.e., along axis L) of a rower's shoe that is disposed on the foot rest 34 in the normal rowing position. In this illustrated embodiment, the first pivot structure 44 is arranged with respect to the second pivot structure 46 such that the first pivot axis P1 is disposed within fifteen millimeters towards to a toe end of the foot-rudder control member 32 from the second pivot axis P2. Thus, in this illustrated embodiment, the first pivot structure 44 is arranged with respect to the second pivot structure 46 such that the first pivot axis P1 is disposed being closer to a toe end of the foot-rudder control member 32 than is the second pivot axis P2 with respect to the toe end of the foot-rudder control member 32.
In this illustrated embodiment, the right shoe support structure 18 is further provided with a positioning structure 48 that selectively retains the foot-rudder control member 32 from pivoting on the first pivot axis P1 to maintain the foot-rudder control member 32 in a center position with respect to the base 30. When the foot-rudder control member 32 in the center position by the positioning structure 48, the rudder 22 is held in the non-angled (center) position with respect to the boat 10. While the positioning structure 48 is illustrated with only one position, several positions can be provided if needed and or desired.
Turning now to
The frame part 50 is formed of a plurality of tubular members. As best seen in
As seen in
In this illustrated embodiment, as seen in
As seen in
As seen in
Referring to
In this illustrated embodiment, as seen in
As seen in
In this illustrated embodiment, as seen in
Referring to
As mentioned above, the left shoe support structure 20 basically includes the base 40, the footrest member 42 and the heel support member 54. The footrest member 42 constitutes an additional footrest member with respect to the footrest member 34. The base 40 is stationary with respect to the boat 10, while the footrest member 42 is pivotally mounted to the base 40 to pivot about a third pivot axis P3. When the positioning structure 48 is retaining the foot-rudder control member 32 in the center position with respect to the base 30, the second and third pivot axes P2 and P3 are coincident as seen in
In this illustrated embodiment, the second pivot structure 46 of the footrest member 34 is also used for pivotally supporting the footrest member 42 of the left shoe support structure 20 relative to the base 40. The pivot structure 46 of the footrest member 42 constitutes a third pivot structure pivotally supporting the footrest member 42 on the base 40 to change a shoe inclination of the footrest member 42 with respect to the base 40. The (third) pivot structure 46 of the footrest member 42 defines the third pivot axis P3 of pivotal movement between the additional footrest member 42 and the base 40. The first and third pivot axes P1 and P3 are substantially perpendicular to each other. However, the footrest member 42 of the left shoe support structure 20 is fixed to a support plate 69. The support plate 69 is fixed by four bolts to the base 40 in a longitudinal adjustable manner. Thus, the footrest member 42 cannot be used to operate the rudder 22 in this illustrated embodiment.
In this illustrated embodiment, the footrest members 34 and 42 are identical. Thus, only the footrest member 34 will be discussed. The footrest member 34 is supported on the foot-rudder control member 32 to pivot or swing about the second pivot axis P2 with respect to the foot-rudder control member 32. In this illustrated embodiment, the footrest member 34 is a cleat type shoe attachment mechanism. In such a clipless type shoe attachment mechanism, a shoe includes a cleat or attachment part (not shown) that is releasably retained by the footrest member 34 in a conventional manner.
Basically, the footrest member 34 includes a support part 70, a front cleat retraining member 72, a rear cleat retraining member 74 and a pair of biasing elements 76. The support part 70 of the footrest member 34 is fixedly attached to the second pivot structure 46 such that the footrest member 34 pivots or swings about the second pivot axis P2 with respect to the foot-rudder control member 32. The front cleat retraining member 72 is fixed to the support part 70 of the footrest member 34, while the rear cleat retraining member 74 is pivotally coupled to the support part 70 of the footrest member 34 by a pivot pin. The biasing elements 76 are torsion springs that are mounted on the pivot pin of the rear cleat retraining member 74 for urging the rear cleat retraining member 74 to a cleat engaging position. Thus, the cleat retraining members 72 and 74 with the biasing elements 76 constitute a step-in shoe attachment structure of the footrest member 34. The first pivot axis P1 is located adjacent the step-in shoe attachment structure of the footrest member 34. In this illustrated embodiment, the first pivot axis passes through the front cleat retraining member 72 of the step-in shoe attachment structure of the footrest member 34.
When the footrest member 34 is pivoted or swung about the second pivot axis P2 so that the rear cleat retraining member 74 contacts the release lever plate 66, further movement of the footrest member 34 against the release lever plate 66 cause the rear cleat retraining member 74 to pivot to a cleat releasing position against the urging forces of the biasing elements 76. In this way, the rower's shoe can be easily released from between the cleat retraining members 72 and 74. A similar clipless type shoe attachment mechanism is disclosed in U.S. patent application Ser. No. 12/361,594, filed on Jan. 29, 2009 and assigned to Shimano Inc. Other examples of clipless type shoe attachment mechanisms are disclosed in U.S. Pat. No. 6,119,551 assigned to Shimano Inc. and U.S. Pat. No. 6,925,908 assigned to Shimano Inc.
In this illustrated embodiment, the right and left footrest members 34 and 42 are each independently adjustable in the longitudinal direction of the rowing boat 10. Also the right and left heel support members 54 are independently adjustable in the longitudinal direction of the rowing boat 10. However, it will be apparent to those skilled in the art from this disclosure that these adjustment features do not need to be included in the rowing boat footrest assembly 12.
Referring to
Basically, the pivot nut 80 is fixed on a shaft 86a of the pivot bolt 86. In particular, the pivot nut 80 is provided with a threaded bore 80a, as seen in
In this illustrated embodiment, at least a portion of the threaded bore 80a of the pivot nut 80 is dimensioned to at least partially deform upon the thread of the shaft 86a of the pivot bolt 86 being screwed into the threaded bore 80a of the pivot nut 80. This arrangement of the threaded bore 80a of the pivot nut 80 is designed to prevent the pivot nut 80 from loosening from the pivot bolt 86. Since the pivot nut 80 is maintained in a set position on the shaft 86a of the pivot bolt 86, the upper pivot bushing 81 is also maintained in a set position on the shaft 86a of the pivot bolt 86, and an urging force of the biasing element 83 is maintained at a desired level.
The upper pivot bushing 81 is axially disposed between the pivot nut 80 and the foot-rudder control member 32 with respect the axial direction of the first pivot axis P1. As mentioned above, the upper pivot bushing 81 is threaded onto the shaft 86a of the pivot bolt 86, and is non-rotatably coupled to the foot-rudder control member 32 by the non-circular flange 81b that mates with a corresponding recess in the upper surface of the foot-rudder control member 32. Thus, the pivot bolt 86 is effectively fixed to the foot-rudder control member 32. Since the pivot nut 80 is threaded on the shaft 86a of the pivot bolt 86, the upper pivot bushing 81 is held in a set position by the pivot nut 80. In this way, the upper pivot bushing 81 is first threaded onto the shaft 86a of the pivot bolt 86 until the desired spacing between the foot-rudder control member 32 and the support plate 52 is attained to reach a desired biasing force between the foot-rudder control member 32 and the support plate 52 by the biasing element 83. After the upper pivot bushing 81 is set to the desired position, the pivot nut 80 is threaded on the shaft 86a of the pivot bolt 86 to retain the upper pivot bushing 81 in the desired position due to the deformation of the threaded bore 80a from the shaft 86a of the pivot bolt 86 being screwed into the threaded bore 80a.
As best seen in
The pivot biasing element 83 is disposed operatively between the support plate 52 of the base 30 and the foot-rudder control member 32 such that the pivot biasing element 83 applies an urging force biasing the foot-rudder control member 32 away from the support plate 52 of the base 30. More specifically, the pivot biasing element 83 is axially disposed between the upper pivot washer 82 and the lower pivot washer 84 with respect the axial direction of the first pivot axis P1. The pivot biasing element 83 includes at least one cone shaped spring (only one used in the illustrated embodiment). Accordingly, the pivot biasing element 83 is provided to obtain a desirable control friction of the foot-rudder control member 32. The desirable control friction can be obtained by adjusting tightening torque of the pivot bolt 86 to the upper pivot bushing 81. Once the pivot nut 80 is attached and deformed (fixed) to the pivot bolt 86, the control friction cannot be further adjusted.
As seen in
The lower pivot washer 84 has a projection 84a that is arranged with respect to the foot-rudder control member 32 to limit pivotal movement between the foot-rudder control member 32 with respect to the support plate 52 of the base 30. In particular, the projection 84a selectively contacts the abutments 32c of the foot-rudder control member 32 to limit pivotal movement between the foot-rudder control member 32 and the support plate 52 of the base 30.
As mentioned above, the lower pivot bushing 85 is non-rotatably coupled to the support plate 52 of the base 30 in that the non-circular shaft 85a of the lower pivot bushing 85 mates with the non-circular opening 52a of the support plate 52. The lower pivot bushing 85 is disposed on the shaft 86a of the pivot bolt 86 between the support plate 52 of the base 30 and the upper pivot bushing 81 that is non-rotatably coupled to the foot-rudder control member 32.
Referring back to
Referring mainly to
In this illustrated embodiment, the housing 90 is a separate member that is fixed to the support plate 52 of the base 30 by a pair of screws (
However, the positioning structure 48 is not limited to this illustrated configuration. The positioning structure 48 can have other configurations such that certain parts are unified. For example, the housing 90 can be unified with either the foot-rudder control member 32 or the support plate 52, as need and/or desired. Also, the biasing member 94 can be unified with the contact member 92 such that the contact member 92 and the biasing member 94 are a one piece, unitary member. For example, a contact member and a biasing member can be made from a single bent leaf spring with a centrally located detent that forms the contact member. Also the setting member 98 can be arranged to some other member other than the housing 90. For example, a setting member can be arranged on the foot-rudder control member 32 so that the setting member 98 effectively varies the position of the notch with respect to the contract member.
In this illustrated embodiment, the housing 90 has a threaded bore 90a, a recess 90b and a slot 90c. The threaded bore 90a communicates with the recess 90b which in turn communicates with the slot 90c. The setting member 98 is screwed into the threaded bore 90a. The position of the setting member 98 with respect to the housing 90 can be adjusted based on the amount that the setting member 98 is screwed into the threaded bore 90a. In this way, the urging force of the biasing member 94 on the contact member 92 can be adjusted.
In this illustrated embodiment, the access opening 52b of the support plate 52 is at least partially aligned with the recess 90b of the housing 90 once the housing 90 is fixed to the support plate 52. The access opening 52b is a circular opening that is dimensioned for selectively inserting and/or removing the contact member 92 from the recess 90b of the housing 90 through the access opening 52b with the housing 90 being fixed to the support plate 52. Thus, the access opening 52b is configured and arranged to aid in the installation and/or disablement of the positioning structure 48.
The housing 90 also has a mounting surface 90d that faces an upper support surface of the support plate 52 of the base 30 to which the housing 90 is attached. This mounting surface 90d defines a periphery of the recess 90b of the housing 90. In other words, the mounting surface 90d includes the recess 90b that houses the contact member 92 and the biasing member 94.
In this illustrated embodiment, the contact member 92 is positioned in the recess 90b of the housing 90 and slidably retained on the upper surface of the support plate 52 of the base 30. While the contact member 92 is illustrated as a rod shaped member, it will be apparent from this disclosure that the contact member 92 can have other shapes as a sphere. The biasing member 94 is positioned in the recess 90b of the housing 90 between the contact member 92 and the setting member 98. Thus, the contact member 92 is biased towards the slot 90c of the housing 90. The slot 90c of the housing 90 receives a portion of the foot-rudder control member 32 in which the resin control plate 64 is attached. Thus, the biasing member 94 urges the contact member 92 into contact with the recess 100 that is formed the resin control plate 64 and the foot-rudder control member 32. The contact member 92 is located in the recess 100 of the foot-rudder control member 32 (e.g., the pivotal support plate) such that the foot-rudder control member 32 is held in the predetermined angular position of with respect to the base 30. In this illustrated embodiment, the predetermined angular position is an intermediate position between two end positions of a prescribed range of pivotal movement of the foot-rudder control member 32 with respect to the base 30.
In particular, as mentioned above, in this illustrated embodiment, the foot-rudder control member 32 constitutes a pivotal support plate. The contact member 92 is biased into contact with a peripheral edge of the pivotal support plate that forms at least a part of the foot-rudder control member 32. Thus, the slot 90c of the housing 90 receives a portion of the peripheral edge of the foot-rudder control member 32 (e.g., the pivotal support plate), which is movably disposed in the slot 90c of the housing 90. Also a portion of the contact member 92 is movably disposed in the slot 90c of the housing 90. In this way, in this illustrated embodiment, the peripheral edge of the foot-rudder control member 32 has the recess 100 for selectively receiving the contact member 92 to maintain the foot-rudder control member 32 in a predetermined angular position (e.g., a center position in the illustrated embodiment) with respect to the base 30 unless a force is applied that overrides urging force of the biasing member 94 on the contact member 92.
In this illustrated embodiment, the biasing member 94 is a coil compression spring that is preload in its assembled position to apply an urging force on the contact member 92 for biasing the contact member 92 into contact with the recess 100 on the peripheral edge of the foot-rudder control member 32. The biasing member 94 has one end directly contacting the setting member 98 and the other end directly contacting the contact member 92.
In this illustrated embodiment, the setting member 98 is adjustably arranged to change the urging force of the biasing member 94 on the contact member 92. Thus, the setting member 98 constitutes a biasing force adjustment setting member of the positioning structure 48. The setting member 98 has a threaded portion 98a and a projection 98b. The setting member 98 is threadedly disposed in the threaded bore 90a of the housing 90. The projection 98b receives one end of the biasing member 94 to maintain the correct orientation of the biasing member 94 within the recess 90b of the housing 90. By changing the amount that the threaded portion 98a is screwed into the threaded bore 90a of the housing 90, the urging force on the contact member 92 can be easily changed based on the position of the setting member 98 within the threaded bore 90a of the housing 90.
Referring now to
In this second illustrated embodiment, a modified foot-rudder control member 132 is pivotally supported on a modified support plate 152 about the first pivot axis P1 using the first pivot structure 44 of the first embodiment. Also the positioning structure 48 of the first embodiment is used to selectively retain the foot-rudder control member 132 from pivoting with respect to the support plate 152 on the first pivot axis P1. In this second illustrated embodiment, two of the footrest members 34 are pivotally supported on the foot-rudder control member 132 to pivot or swing about the second pivot axis P2 with respect to the foot-rudder control member 32 by a pair of the second pivot structures 46, respectively. Thus, in this second illustrated embodiment, the foot-rudder control member 132 includes an additional footrest member with a step-in shoe attachment structure, as compared to the first embodiment. In this way, the rower controls the rudder 22 by pivoting both of the footrest members 34 together about the first pivot axis P1.
Referring now to
The positioning structure 248 mainly includes a housing 290, a contact member 292, a biasing member 294 and a notch or recess 296 in the resin control plate 264. In this illustrated embodiment, the resin control plate 264 constitutes a biasing force adjustment setting member of the positioning structure 248. By changing the position of the resin control plate 264 on the foot-rudder control member 232, the effective biasing force of the biasing member 294 is adjusted. Other than the way in which the biasing force is adjusted, the operation and the function of the positioning structure 248 is the same as the positioning structure 48. Thus, the positioning structure 248 will not be discussed in further detail.
Referring now to
In this illustrated embodiment, the depression 364a of the resin control plate 364 constitutes part of the positioning structure 348. In addition to the depression 364a of the resin control plate 364, the positioning structure 348 mainly includes a housing 390, a contact member 392, a biasing member 394 and a setting member 398. In this illustrated embodiment, the setting member 398 is adjustably arranged to change the urging force of the biasing member 394 on the contact member 392. The setting member 398 is threadedly disposed in the threaded bore 390a of the housing 390. By change the position of the setting member 398 within the threaded bore 390a by screwing the setting member 398 in or out of the threaded bore 390a, the effective biasing force of the biasing member 394 is adjusted. Thus, the setting member 398 constitutes a biasing force adjustment setting member of the positioning structure 348. Other than the way in which the biasing force is adjusted, the operation and the function of the positioning structure 348 is the same as the positioning structure 48. Thus, the positioning structure 348 will not be discussed in further detail.
In understanding the scope of the present invention, the term “comprising” and its derivatives, as used herein, are intended to be open ended terms that specify the presence of the stated features, elements, components, groups, integers, and/or steps, but do not exclude the presence of other unstated features, elements, components, groups, integers and/or steps. The foregoing also applies to words having similar meanings such as the terms, “including”, “having” and their derivatives. Also, the terms “part,” “section,” “portion,” “member” or “element” when used in the singular can have the dual meaning of a single part or a plurality of parts. As used herein to describe the above embodiment(s), the following directional terms “forward”, “rearward”, “above”, “downward”, “vertical”, “horizontal”, “below” and “transverse” as well as any other similar directional terms refer to those directions of a boat equipped with the rowing boat footrest assembly. Accordingly, these terms, as utilized to describe the rowing boat footrest assembly should be interpreted relative to a boat equipped with the rowing boat footrest assembly as used in the normal rowing position. Finally, terms of degree such as “substantially”, “about” and “approximately” as used herein mean a reasonable amount of deviation of the modified term such that the end result is not significantly changed.
While only selected embodiments have been chosen to illustrate the present invention, it will be apparent to those skilled in the art from this disclosure that various changes and modifications can be made herein without departing from the scope of the invention as defined in the appended claims. For example, the size, shape, location or orientation of the various components can be changed as needed and/or desired. Components that are shown directly connected or contacting each other can have intermediate structures disposed between them. The functions of one element can be performed by two, and vice versa. The structures and functions of one embodiment can be adopted in another embodiment. It is not necessary for all advantages to be present in a particular embodiment at the same time. Every feature which is unique from the prior art, alone or in combination with other features, also should be considered a separate description of further inventions by the applicant, including the structural and/or functional concepts embodied by such feature(s). Thus, the foregoing descriptions of the embodiments according to the present invention are provided for illustration only, and not for the purpose of limiting the invention as defined by the appended claims and their equivalents.
| Number | Name | Date | Kind |
|---|---|---|---|
| 231017 | Davis | Aug 1880 | A |
| 4228756 | Storer, Jr. | Oct 1980 | A |
| 5367976 | Van Schaik | Nov 1994 | A |
| 6739277 | Knight | May 2004 | B2 |
| 8051794 | Matsueda et al. | Nov 2011 | B2 |
| 8069803 | Crawford | Dec 2011 | B1 |
| 20090205556 | Kawahara et al. | Aug 2009 | A1 |
| 20090241827 | Matsueda et al. | Oct 2009 | A1 |
| 20100018450 | Matsueda et al. | Jan 2010 | A1 |
| Number | Date | Country | |
|---|---|---|---|
| 20110315066 A1 | Dec 2011 | US |
