Patent Grant
10688353
The present invention relates to a golf club head, more particularly to an iron-type golf club head capable of improving the flying distance and directionality of a ball hit by an average golfer.
In general, an iron-type golf club head is designed such that, when a ball is hit at a suitable position such as the sweet spot or the center of the club face, the flying distance of the ball becomes maximum. However, it is difficult For the average golfers to hit a ball at such a suitable position every time. Therefore, in the case of the average golfers, there is a tendency that the flying distance varies wide.
In the circumstances described above, for example, in the Japanese Patent Application Publication Nos. H9-253248 and H10-295861, an iron-type golf club head in which the position of the center of gravity of the club head is lowered has been proposed. Such a club head accordingly has the sweet spot at a lower position on the club face.
In general, an iron-type golf club has many opportunities to hit a ball lying on lawn, therefore, the ball hitting position tends to become in a sole-side region of the club face. Accordingly, in the case of the above-mentioned club head, the actual ball hitting position tends to coincide with the sweet spot. This helps to improve the flying distance.
In the case of a golf club head whose center of gravity is further lowered, chances of hitting a ball on the upper side of the sweet spot become high.
If a ball is hit on the upper side of the sweet spot, the club head is rotated by a small angle so as to increase the loft angle, and the launch angle of the ball is increased accordingly. Thereby, due to the gear effect, the excessive backspin of the ball is prevented. Thus, in this respect too, the club head having the lowered center of gravity is advantageous to increasing the flying distance.
In recent years, on the other hand, an iron-type golf club head constructed to have a large moment of inertia has been proposed. In the Japanese Patent Application Publication No. 2014-410, such a club head is disclosed, wherein the moment of inertia about the Y-axis (vertical axis) extending through the center of gravity of the club head is increased.
In the case of the club head increased in the moment of inertia, even if the ball hitting position is off-centered toward the toe or heel from the sweet spot of the club face, the club head is hard to be rotated around the vertical axis at impact. Thus, such a club head having a large moment of inertia can improve the directionality of the ball hit by an average golfer.
From the results of study made by the inventor, it was found that the prior iron-type golf club heads have room for improvement to successfully satisfy the flying distance and the directionality of the hit ball at the same time.
It is therefore, an object of the present invention to provide an iron-type golf club head which can improve the flying distance and directionality of a ball hit by an average golfer.
According to the present invention, an iron-type golf club head having a club face provide with a plurality of grooves extending in the toe-heel direction, is characterized by satisfying the following conditions (1)-(4):
(1) the loft angle is not more than 41 degrees,
(2) the thickness of the club head is not more than 23 mm,
(3) the height of the club face measured along the club face at the position in the toe-heel direction of the most toe-side end of the grooves is not less than 53 mm,
(4) in a standard state of the club head, the ratio M/Sh (g sq·cm/mm) of
a moment M of inertia (g sq·cm) around a first axis passing through the sweet spot in parallel with the club face and perpendicularly to the grooves, and
a sweet spot height Sh (mm) which is the vertical height from the horizontal plane to the sweet spot is not less than 152.
In this application, dimensions, positions, directions and the like relating to the club head refer to those under a standard state of the club head unless otherwise noted.
Here, the standard state of the club head is such that the club head is set on a horizontal plane HP so that the axis CL of the club shaft (not shown) is inclined at the specified lie angle alpha while keeping the axis CL on a vertical plane v, and the club face forms the specified loft angle beta. Incidentally, in the case of the club head alone, the center line of the shaft inserting hole can be used instead of the axis CL of the club shaft.
The sweet spot is a point of intersection between the club face 4 and a straight line drawn normally to the club face passing the center G of gravity of the golf club head.
The front-back direction is a direction parallel with the above-mentioned straight line projected on the horizontal plane HP.
The toe-heel direction is a direction parallel with the horizontal plane HP and perpendicular the a front-back direction.
Further, the iron-type golf club head according to the present invention may have the following features (a)-(e):
(a) the sweet spot height Sh is not more than 20 mm;
(b) the moment M of inertia is not less than 3000 (g sq·cm);
(c) the iron-type golf club head includes a head main body having a sole, and a weight member whose specific gravity is larger than the head main body, wherein
the head main body is provided in the sole with a channel extending in the toe-heel direction,
the weight member is fixed to the channel,
the weight member includes a toe-side weight member fitted in a toe-side part of the channel, a heel-side weight member fitted in a heel-side part of the channel, and a sole cover fixed to the channel so as to cover the toe-side weight member and the heel-side weight member;
(d) each of the toe-side weight member and the heel-side weight member has a specific gravity more than that of the sole cover;
(e) the toe-side weight member has a specific gravity more than that of the heel-side weight member.
According to the present invention, therefore, by satisfying the conditions (1)-(4), the iron-type golf club head can achieve both of the increased moment of inertia and the lowered sweet spot height. Thereby, it is possible to significantly improve the flying distance and the directionality of a ball hit by an average golfer.
Embodiments of the present invention will now be described in detail in conjunction with accompanying drawings.
As shown, the club head 1 includes a main portion 2 and a hosel portion 3.
The main portion 2 includes a club face 4, a top 5, a sole 6, a toe 7 and a heel 10.
The club face 4 is a substantially flat surface for hitting a ball. The club face 4 is provided with grooves 8 extending in the toe-heel direction.
Each of the grooves 8 has a small width and a small depth according to the limitations provided in the Golf rules. Under the standard state of the club head 1, each of the grooves 8 extends in the horizontal direction.
The grooves 8 increase the frictional coefficient of the club face 4 to give appropriate spin to the hit ball to improve the flying distance.
Given that a grooved range is a range defined as extending in the toe-heel direction between a position in the toe-heel direction of the most toe-side end 8a of the grooves 8, and a position in the toe-heel direction of the most heel-side end 8b of the grooves 8, the grooved range has a width in the toe-heel direction determined in view of variations of ball hitting positions of the average golfers, and the grooved range is positioned substantially at the center in the toe-heel direction of the club face 3.
The cross section shown in
The above-mention top 5 is the upper part of the club head 1 extending backward of the club head from the upper edge of the club face 4.
The sole 6 is the lower part of the club head 1 extending backward of the club head from the lower edge of the club face 4.
The toe 7 is a part which is most distant from the hosel portion 3 and smoothly connects between the top 5 and the sole 6.
The heel 10 is a part on the opposite side of the toe 7 of the club head 1.
The hosel portion 3 is tubular in this example, and has a shaft inserting hole 9 into which a club shaft (not shown) is inserted.
According to the present invention, the club head 1 is characterized by satisfying the following conditions:
(1) a loft angle is not more than 41 degrees,
(2) a thickness of the club head is not more than 23 mm,
(3) a height of the club face is not less than 53 mm, and
(4) the ratio M/Sh (g sq·cm/mm) of a moment M of inertia (g sq·cm) around a first axis passing through the sweet spot SS in parallel with the club face 4 and perpendicularly to the grooves 8 as shown in
The conditions (1), (2) and (3) are for determining iron-type golf club heads targeted by the present invention. Namely, the iron-type golf club heads satisfying the conditions (1), (2) and (3) include iron-type golf club heads having conventional shapes, but a sand wedge and a pitching wedge for short game and a utility club are not included.
By the conditions (1), club heads having larger loft angles such as a sand-wedge and a pitching wedge are excluded from the target of the present invention. In the case of such club heads, the flying distance will not become an issue.
According to the conventional relationship between the club number and loft angle, the target of the present invention may be up to nine iron club.
Iron-type golf club heads targeted by the present invention are such that importance is put on both of the flying distance and directionality. For example, iron-type golf club heads having loft angles in a range of from 18 to 41 degrees may be targeted.
Further, the conditions (1)-(3) give a limitation to iron-type club heads which are easy to address. In the case of iron-type clubs satisfying the conditions (1)-(3), the trailing edge of the club head may be out of sight of the golfer when properly addressed. This makes it easy for the average golfer to address.
As shown in
As the target of the present invention, an iron-type golf club head having a thickness Ft of from 15 to 23 mm is suitable.
As shown in
As the target of the present invention, an iron-type golf club head having a height Fh of from 53 to 63 mm is suitable.
The reason why the thickness Ft and the height Fh of the club face are measured at the most toe-side end 8a of the grooves 8 is that the thickness Ft and the height Fh usually become maximum at the above-mentioned position.
The condition (4) defines the ratio M/Sh (g sq·cm/mm) as being not less than 152. The ratio M/Sh (g sq·cm/mm) is that of the moment M of inertia (g sq·cm) around a first axis 11 passing through the sweet spot SS in parallel with the club face 4 and perpendicularly to the grooves 8, and the sweet spot height Sh (mm) which is the vertical height from the horizontal plane HP to the sweet spot SS.
The iron-type golf club head 1 satisfying the conditions (4) can achieve both of a large moment M of inertia and a low sweet spot height Sh.
The value of the moment M of inertia becomes slightly larger than the value of a moment of inertia around a vertical axis passing through the center of gravity of the club head G, and there is a correlation therebetween.
As apparent therefrom, in the case of conventional iron-type golf club heads indicated as comparative examples, if the sweet spot height Sh is low, then the moment M of inertia is small, and if the moment M of inertia is large, then the sweet spot height Sh is also high.
On the other hands, in the case of iron-type golf club heads as embodiments of present invention, the moment M of inertia can be increased while maintaining a low sweet spot height to satisfy the ratio M/Sh of not less than 152. Accordingly, the club head 1 according to the present invention can significantly improve the average golfers' flying distance and directionality.
Preferably, the ratio M/Sh (g sq·cm/mm) is set in a range of not less than 156, more preferably not less than 160.
In so far as the mass of the iron-type golf club head is within a conventional range (for example, 230 to 280 g), it is preferable that the sweet spot height Sh is as low as possible, and the moment M of inertia is as large as possible. Therefore, an upper limit is not given to the ratio M/Sh (g sq·cm/mm).
It is not essential but preferable that the sweet spot height Sh is not more than 21.0 mm, more preferably not more than 20.5 mm, still more preferably not more than 20.0 mm, yet still more preferably not more than 19.8 mm.
It is not essential but preferable that the moment M of inertia is not less than 2900 g sq·cm, more preferably not less than 2950 g sq·cm, still more preferably not less than 3000 g sq·cm.
As shown, the structural members of the club head 1 include a head main body 30 and a weight member 50.
Preferably, the head main body 30 includes a face plate 31 forming a major part of the club face 4, and a face plate receiving frame 32 on which the face plate 31 is mounted.
The face plate 31 is made of a material having a specific gravity which is smallest in the structural members of the club head 1. For the face plate 31, a metal material whose specific gravity is not more than 4.5 is preferably used. Especially, the use of a titanium alloy is preferred.
The face plate receiving frame 32 is provided with a though hole O penetrating in the front-back direction of the club head, while being surrounded by the top 5, the sole 6, toe 7 and the heel 10.
The face plate receiving frame 32 is provided around the hole O with a club face mount portion 33 to which a peripheral part of the face plate 31 is fixed.
By the face plate 31 fixed to the club face mount portion 33, the hole O of the face plate receiving frame 32 is closed.
The face plate receiving frame 32 integrally includes the hosel portion 3.
Preferably, the face plate receiving frame 32 is made of an iron-based alloy having strength and good workability. Preferably, stainless steel or carbon steel having a specific gravity of not less than 7.5 can be used. Such face plate receiving frame 32 is helps to increase the moment M of inertia.
The channel 34 extends in the sole 6 along the toe-heel direction as shown in
As shown in
The channel 34 comprises a toe-side channel portion 34a, a heel-side channel portion 34b, and a middle channel portion 34c extending therebetween as shown in
The weight member 50 is fixed to the channel 34.
In this embodiment, the weight member 50 includes three separate members: a toe-side weight member 51, a heel-side weight member 52 and a sole cover 53.
The weight members 51, 52 and 53 each have a specific gravity more than the specific gravity of the head main body 30 (namely, the face plate 31 and the face plate receiving frame 32).
It is preferable that the specific gravity of each weight member 50 (51, 52 and 53) is not less than 9.0.
The toe-side weight member 51 is disposed on the toe-side of the center of the club face FC in order to concentrate the mass at a toe-side part of the club head 1.
The center of the club face FC means the center in the toe-heel direction of the grooved range.
The toe-side weight member 51 has an outer shape such that the toe-side weight member 51 fits into the toe-side channel portion 34a without a space therebetween in substance. Thereby, movements of the toe-side weight member 51 in the upper direction, the front-back direction and the toe-heel direction of the club head are restrained by being inserted in the toe-side channel portion 34a.
The under surface of the toe-side weight member 51 is positioned above the outer surface of the sole 6 so as not to form the outer surface of the sole 6.
It is not essential but preferable that the toe-side weight member 51 is curved upward toward the toe-side. Thereby, it is possible to effectively actualize the lowering of position of the center of gravity and a mass distribution toward a toe-side upper part.
The heel-side weight member 52 is disposed on the heel-side of the center of the club face FC in order to concentrate the mass at a heel-side part of the club head 1.
The heel-side weight member 52 has an outer shape such that the heel-side weight member 52 fits into the heel-side channel portion 34b without a space therebetween in substance. Thereby, movements of the heel-side weight member 52 in the upper direction, the front-back direction and the toe-heel direction of the club head are restrained by being inserted in the heel-side channel portion 34b.
The under surface of the heel-side weight member 52 is positioned above the outer surface of the sole 6 so as not to form the outer surface of the sole 6.
It is not essential but preferable that the heel-side weight member 52 is curved upward toward the heel-side. Thereby, it is possible to effectively actualize the lowering of position of the center of gravity and a mass distribution toward a heel-side upper part.
The sole cover 53 extends in the toe-heel direction across the center of the club face FC. In this embodiment, the sole cover 53 extends in the toe-heel direction over the entire length of the channel 34. Thereby, the sole cover 53 in this embodiment completely covers the toe-side weight member 51 and the heel-side weight member 52 from the under side (sole side).
Preferably, each of the toe-side weight member 51 and the heel-side weight member 52 has a specific gravity more than that of the sole cover 53. Thereby, it is possible to achieve the above-described lowered center of gravity of the club head G and increased moment M of inertia at the same time.
It is especially effective for effectively increasing the moment M of inertia while achieving the lowered center of gravity, to configure the sole cover 53 to have a specific gravity more than that of the head main body 30, and less than those of the toe-side weight member 51 and the heel-side weight member 52. Further, since the hosel portion 3 provides a relatively large mass in a heel side part of the club head 1, in order to balance therewith, the toe-side weight member 51 preferably has a specific gravity more than that of the heel-side weight member 52.
In order to allow the ratio M/Sh in a preferable range, it is desirable that
the specific gravity of the toe-side weight member 51 is more than 14, preferably not less than 15, more preferably not less than 16,
the specific gravity of the heel-side weight member 52 is more than 10, preferably not less than 11, more preferably not less than 13, and
the specific gravity of the sole cover 53 is not more than 9 and not less than 10.
In this embodiment, the weight members 51, 52 and 53 are each made of a tungsten-nickel-iron alloy containing w, Ni and Fe. The specific gravity of each of the weight members 51, 52 and 53 can be adjusted by mainly changing the content of tungsten W having a large specific gravity.
In this embodiment, the alloy materials of the toe-side weight member 51 and the heel-side weight member 52 each has a content of tungsten w more than that of the alloy material of the sole cover 53 so as to have a specific gravity more than that of the sole cover 53.
The weldability of the tungsten-nickel-iron alloy with the iron-based alloy of the head main body 30 is decreased with the increase in the content of w. Accordingly, if a tungsten-nickel-iron alloy having a high tungsten content is used as the toe-side weight member 51 and the heel-side weight member 52, it becomes difficult to make a strong weld joint between the head main body 30 of the iron-based alloy and the toe-side weight member 51 and the heel-side weight member 52.
However, the sole cover 53 whose tungsten content is lower than the toe-side weight member 51 and the heel-side weight member 52 has a better weldability with the iron-based alloy than those of the weight members 51 and 52.
Therefore, in this embodiment, the sole cover 53 is fixed to the head main body 30 (face plate receiving frame 32) by welding. But, the toe-side weight member 51 and the heel-side weight member 52 are not welded to the face plate receiving frame 32 and the sole cover 53. Accordingly, the toe-side weight member 51 and the heel-side weight member 52 are fixedly held in an interior space of the club head defined by the head main body 30 and the sole cover 53, essentially by being closely fitted therewith.
When fixing the three weight members 51-53 to the head main body 30, the toe-side weight member 51 and the heel-side weight member 52 can be easily located at their proper positions by fitting these into the toe-side channel portion 34a and the heel-side channel portion 34b.
Then, by welding only the sole cover 53 to the channel 34 of the head main body 30, the weight members 51-53 can be fixed to the head main body 30.
In the club head 1 in this embodiment, accordingly, the weight members can be fixed to the head main body 30 with a simple process.
Preferably, the sole cover 53 comprises a toe-side thin portion 53a, a heel-side thin portion 53b and an in-between thick portion 53c extending therebetween as shown in
The toe-side thin portion 53a is a portion located beneath the toe-side weight member 51.
The heel-side thin portion 53b is a portion located beneath the heel-side weight member 52.
It is desirable that the toe-side thin portion 53a and the heel-side thin portion 53b are made as thin as possible. Thereby, while giving a large mass to the toe side and heel side, the toe-side weight member 51 and the heel-side weight member 52 can be positioned on the further lower side (toward the outer surface of the sole 6). Therefore, the club head can be provided with the further lowered center of gravity.
Preferably, the thickness t1 of the toe-side thin portion 53a and the thickness t2 of the heel-side thin portion 53b are set in a range of not more than 3.0 mm, more preferably not more than 2.5 mm, still more preferably not more than 2.0 mm.
The thickness t3 of the in-between thick portion 53c is more than the thickness t1 of the toe-side thin portion 53a and the thickness t2 of the heel-side thin portion 53b.
Due to such thickness variation, the upper surface of the sole cover 53 has a step 54 at the boundary between the in-between thick portion 53c and the toe-side thin portion 53a, and a step 55 at the boundary between the in-between thick portion 53c and heel-side thin portion 53b.
The steps 54 and 55 can closely contact with the toe-side weight member 51 and the heel-side weight member 52 disposed in the channel 34 without being welded, therefore, their positions in the toe-heel direction are more certainly fixed. Thereby, unpleasant hit feeing and sound can be prevented.
Preferably, the thickness t3 of the in-between thick portion 53c is gradually increased towards the toe. Such sole cover 53 helps to increase a mass distribution toward the toe while achieving the lowering of position of the center of gravity. This helps to further increase the ratio M/Sh (g sq·cm/mm).
In this example, in order to assure the positioning of the heel-side weight member 52, a temporary fixing part 60 is used.
The temporary fixing part 60 is formed by solidifying a molten metal material. Preferably, the molten metal material is the same metal material as that of the head main body 30 (in particular, the face plate receiving frame 32) or a metal material whose major component is the same as the major component the head main body 30 (in particular, the face plate receiving frame 32).
After the heel-side weight member 52 is fitted in the heel-side channel portion 34b, for example, molten stainless steel as the temporary fixing part 60 is attached to spots arranged along the boundary between the heel-side weight member 52 and the heel-side channel portion 34b.
Preferably, the temporary fixing part is bent into a hook as shown in
Although not shown, it is of course possible to apply such temporary fixing part 60 to the toe-side weight member 51 in the same manner as described above.
While detailed description has been made of preferable embodiments of the present invention, the present invention can be embodied in various forms without being limited to the illustrated embodiment
Comparison Tests
Based on the structure and shape shown in
Further, a club head as comparative example made up of a face plate (a), a face plate receiving frame (b) and a weight member (c) integrated with a hosel portion (d) as shown in
Specifications of these club heads are as follows.
<Common Specifications>
club head: for six iron club
lie angle alpha: 61.5 degrees
loft angle beta: 27 degrees
weight members' materials: tungsten-nickel-iron alloys
toe-side weight member's specific gravity: 16
heel-side weight member's specific gravity: 14
sole cover's specific gravity: 9.5
face plate's material: titanium alloy (specific gravity: 4.4)
face plate receiving frame's material: SuS630
weight member's material: tungsten-nickel-iron alloy
As shown in
<Moment of Inertia>
The moment M of inertia around the first axis 11 under the standard state of the club head as shown in
<Flying Distance and Directionality>
The club heads were attached to identical FRP shafts to make #6 iron clubs. Then, using the #6 iron clubs, each of ten average golfers having average scores ranging from 85 to 100 hit golf balls lying on lawn twenty times per club to obtain the flying distance of the struck ball and the distance of the point of fall of the struck ball from the target trajectory was measured in each shot regardless of slice or hook. For each of the clubs, two hundred measurements obtained from the ten golfers were averaged, and the averaged values are shown in Table 1.
From the test results, it was confirmed that working examples were increased in the ratio M/Sh and improved in the average golfers' flying distance and directionality.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2015-113660 | Jun 2015 | JP | national |
| Number | Name | Date | Kind |
|---|---|---|---|
| 6592469 | Gilbert | Jul 2003 | B2 |
| 6921344 | Gilbert | Jul 2005 | B2 |
| 7192362 | Gilbert | Mar 2007 | B2 |
| 7390270 | Roberts | Jun 2008 | B2 |
| 7815523 | Knutson | Oct 2010 | B2 |
| 9901792 | Franklin | Feb 2018 | B2 |
| 9950219 | Larson | Apr 2018 | B2 |
| 10004957 | Franz | Jun 2018 | B2 |
| 10046211 | Franklin | Aug 2018 | B2 |
| 20010001774 | Antonious | May 2001 | A1 |
| 20030078112 | Sugimoto | Apr 2003 | A1 |
| 20030181259 | Shimazaki | Sep 2003 | A1 |
| 20060234811 | Gilbert | Oct 2006 | A1 |
| 20070254749 | Nakamura | Nov 2007 | A1 |
| 20090221382 | Soracco | Sep 2009 | A1 |
| 20100137074 | Gilbert | Jun 2010 | A1 |
| 20100160076 | Ling | Jun 2010 | A1 |
| 20100261540 | Roach | Oct 2010 | A1 |
| 20100267463 | Stites | Oct 2010 | A1 |
| 20100304887 | Bennett | Dec 2010 | A1 |
| 20110124432 | Oldknow | May 2011 | A1 |
| 20110207551 | Breier | Aug 2011 | A1 |
| 20110250985 | Stites | Oct 2011 | A1 |
| 20120122606 | Yamamoto | May 2012 | A1 |
| 20120289360 | Breier | Nov 2012 | A1 |
| 20120295729 | Matsunaga | Nov 2012 | A1 |
| 20130150178 | Rollinson | Jun 2013 | A1 |
| 20130165257 | Dipert | Jun 2013 | A1 |
| 20130331201 | Wahl | Dec 2013 | A1 |
| 20130344988 | Hettinger | Dec 2013 | A1 |
| 20140357400 | Schweigert | Dec 2014 | A1 |
| 20150024864 | Jertson | Jan 2015 | A1 |
| 20150126301 | Taylor | May 2015 | A1 |
| 20150165281 | Ines | Jun 2015 | A1 |
| 20150182816 | Radcliffe | Jul 2015 | A1 |
| 20150182817 | Oldknow | Jul 2015 | A1 |
| 20150231454 | Parsons | Aug 2015 | A1 |
| 20150328508 | Parsons | Nov 2015 | A1 |
| 20160038796 | Taylor | Feb 2016 | A1 |
| 20160158607 | Parsons | Jun 2016 | A1 |
| 20160184665 | Nakamura | Jun 2016 | A1 |
| 20160193508 | Issertell | Jul 2016 | A1 |
| 20160243413 | Ritchie | Aug 2016 | A1 |
| 20160287955 | Ritchie | Oct 2016 | A1 |
| 20160296804 | Parsons | Oct 2016 | A1 |
| 20160354650 | Norimura | Dec 2016 | A1 |
| 20170216684 | Parsons | Aug 2017 | A1 |
| 20170246517 | Ueda | Aug 2017 | A1 |
| 20170252613 | Daraskavich | Sep 2017 | A1 |
| 20170259134 | Ines | Sep 2017 | A1 |
| 20170340928 | Parsons | Nov 2017 | A1 |
| 20180093144 | Ripp | Apr 2018 | A1 |
| 20180117425 | Taylor | May 2018 | A1 |
| 20180169488 | Parsons | Jun 2018 | A1 |
| 20180189758 | Beach | Jul 2018 | A1 |
| 20180221727 | Parsons | Aug 2018 | A1 |
| 20180229089 | Parsons | Aug 2018 | A9 |
| 20180256946 | Stokke | Sep 2018 | A1 |
| Number | Date | Country |
|---|---|---|
| 9-253248 | Sep 1997 | JP |
| 10-295861 | Nov 1998 | JP |
| 2014-410 | Jan 2014 | JP |
| Number | Date | Country | |
|---|---|---|---|
| 20160354650 A1 | Dec 2016 | US |
