Patent Application
20050161351
This application claims benefit of priority under 35 USC 119 based on Japanese Patent Application P2001-341296 filed Nov. 6, 2001, the entire contents of which are incorporated by reference herein.
The present invention relates to a golf bag having a particularly stable base, and more particularly to a golf bag having a base with protrusions that correspond to mechanisms by which a golf bag falls over.
A golf bag is formed as a tall structure for accommodating golf clubs, and the weight of the accommodated golf clubs is concentrated at the upper portion of the golf bag. When a golf bag with such a structure is set upright on the ground, it is apt to fall over.
To increase stability, it is considered effective to increase the size of the base. The base diameter for a large size golf bag is as wide as 10 inches.
A general golf bag is equipped with a grip for carrying the golf bag. Since golf clubs accommodated in the golf bag are composed of a shaft and a head having the center of gravity at a position offset from the shaft axial line, the heads are aligned in a specific direction, projecting in a direction opposite from the grip after carrying it, and the position of these clubs can exert a force that causes the golf bag to fall down.
Furthermore, golf bags typically are furnished with a front pocket at the grip side and a back pouch at the opposite side. When these pockets are filled, especially when the back pouch is filled with articles, the golf bag becomes even more likely to fall in the opposite direction from the grip.
Japanese Laid-open Utility Model No. 62-72672 discloses protrusions formed near the base on the grip side of the golf bag, but this approach has been found not to be fully satisfactory.
There also exist bases formed in an elliptical shape having the major elliptical axis aligned with the grip and the opposite side (hereinafter called a front-rear direction as shown in
When a base is larger, however, the mass of the base also increases. Although the center of gravity of the golf bag goes down with the increase of the base mass and the stability is improved, the golf bag itself becomes heavier, thus making it hard to handle. It also becomes hard to handle when a base is formed in a polygonal shape. When the inside diameter of a golf bag base is increased, golf clubs in the bag rest against a top frame of the golf bag on one side with the grip ends of the clubs touching against the inner bottom of the other side of the golf bag. This increases the inclination of the golf clubs and also increases the force tending to cause the golf bag to fall over.
In summary, golf bags fall over after going through the following steps.
Because partitions at the top of the bag run side to side, as shown in
Because of this, although the arrangement of protrusions as shown in
The rectangular base disclosed in Japanese Laid-open Utility Model No. 5-76470 is designed such that the inclination in the front-rear direction is not transferred to the lateral direction. While it can be expected to have a preventive effect of rotation of a golf bag, the structure is narrow in the lateral direction in order to save space, and therefore, stability in the lateral direction is not necessarily improved.
The golf bag of the present invention solves the above mentioned problems of the prior art, and provides a golf bag that is less likely to fall over without increasing its mass or dimensions, by providing protrusions at the base portion, which prevent rotation of the golf bag and improve its dynamic stability. As used herein, “protrusion” means the entire portion protruded from the plate-like base in the downward and radial directions.
In accordance with the invention, these objects are accomplished by providing a golf bag having a base with protrusion forming regions at a first section ranging from 30 to 60 degrees from a reference line, a second section ranging from 120 to 150 degrees from the reference line, a third section ranging from 210 to 240 degrees from the reference line, and a fourth section ranging from 300 to 330 degrees from the reference line, and having one or more protrusions formed at each of the protrusion forming regions.
As used herein, “a reference line” means a line passing through the center of the base and a point on the base peripheral edge that is closest to a grip of the golf bag.
In a preferred embodiment of the invention, at least a pair of tangents drawn from one of the protrusions in the front-rear direction and at least a pair of tangents drawn from one of the protrusions in the lateral direction pass outside of the base peripheral edge.
As used herein, “a pair of tangents” means, for example, two front-rear tangents 11 at the right side and left side of the base as shown in
In a preferred embodiment, the protruding length of the protrusion from the base peripheral edge may be from 10 mm to 50 mm.
The present invention also provides a golf bag having a base with protrusion forming regions at a first section ranging from 30 to 60 degrees from the reference line, a second section ranging from 120 to 150 degrees from the reference line, a third section ranging from 210 to 240 degrees from the reference line, and a fourth section ranging from 300 to 330 degrees from the reference line, and having one or more protrusions formed at each of the protrusion forming region, in which a tangent drawn from one of the protrusions in the lateral direction passes outside of a base peripheral edge, and an auxiliary protrusion is formed at the positions of 90 degrees and 270 degrees from the reference line.
In a preferred embodiment, the protruding length of the protrusion from the base peripheral edge may be from 10 mm to 50 mm.
In a preferred embodiment of the invention, the protruding length of the auxiliary protrusion from the base peripheral edge is from 8 mm to 20 mm, and the auxiliary protrusion is shorter than the principal protrusions.
In a more preferred embodiment of the invention, all tangents linking the adjacent protrusions pass outside of a base peripheral edge. Also, all tangents linking the adjacent protrusions and all tangents linking the adjacent protrusion and auxiliary protrusion pass outside of the base peripheral edge.
a is a side view of a conventional golf bag shown without a hood.
Preferred embodiments of the invention are described below.
The golf bag of the present invention is provided with a base having protrusion forming regions 5 at a first section 21 ranging from 30 to 60 degrees from a reference line R, a second section 22 ranging from 120 to 150 degrees from the reference line, a third section 23 ranging from 210 to 240 degrees from the reference line, and a fourth section 24 ranging from 300 to 330 degrees from the reference line, and one or more protrusions 2 are formed at each of the protrusion forming region. The reference line R is a line passing through the center 4 of the base and a point 10 on a base peripheral edge 6 that is closest to a grip 32 of the golf bag 31. The angles are measured counterclockwise from the point 10, which is designated as 0 degree. A protrusion forming position is the point on the base peripheral edge 6 intersected by a line linking the graphic center 8 of the protrusion and the center 4 of the base.
Inclination of a golf bag often starts in the front-rear direction as shown in
Furthermore, a pair or plural pairs of tangents 11 drawn from the protrusions 2 in the front-rear direction and a pair or plural pairs of tangents 12 drawn from the protrusions 2 in the lateral direction are arranged such that they pass outside of the base peripheral edge 6.
As long as slipping does not occur between the base 1 and the ground, stability against inclination depends on a minimum diameter of the base 1. Since the height of the center of gravity and the inclination of golf clubs contained in the bag do not change, stability of a golf bag increases when the minimum diameter of the base 1 increases. Therefore, the stability can be increased by making the distance from the base center 4 to the outermost portion of the protrusions 2 longer than the distance from the base center 4 to the base peripheral edge 6 in the front-rear direction in which leaning is initiated and in the lateral direction which is unstable dynamically.
It is preferable that the protrusions 2 protrude a distance L 10 mm to 50 mm from the base peripheral edge 6.
In the experiment, a base having a diameter of 215 mm was used, and circular protrusions of different diameters separate body from the base were formed at the positions of 45 degrees, 135 degrees, 225 degrees, and 315 degrees from the reference line R.
In the test results, A denotes the number of times that a golf bag fell in the front-rear direction, and B denotes the number of times that a golf bag rotated along the base and fell down in the lateral direction.
From the test results, it can be seen that unless the protruding length L of the protrusion from the base peripheral edge is at least 10 mm, the rotary motion of the golf bag causes the golf bag to fall in the lateral direction. Thus, a longer protruding length L improves stability. However, if protruding length L is too long, the golf bag becomes hard to handle or carry. From the test results, the benefit of the protrusions do not increase when the length L exceeds 50 mm, and hence it can be seen that the maximum length of 50 mm is sufficient.
Although the rotation preventive effect varies depending on the shape of a protrusion, the circular protrusion used in this experiment is the least effective. The circular protrusion, however, is a preferable embodiment for practical reasons, since it does not easily get caught accidentally and is easy to handle. Therefore, it can be said that if protruding length L is within this length range, there is sufficient rotation prevention regardless of the shape of protrusion.
A similar experiment was conducted by using a base of 230 mm in diameter with no protrusions. When comparing a base of 215 mm in diameter having protrusions of 10 mm in length formed on the base and the base of 230 mm in diameter with no protrusions, the distance from the base center 4 is approximately the same, about 115 mm in both cases, but the base of 215 mm in diameter having protrusions was found to be less likely to fall than the base of 230 mm in diameter with no protrusions.
In another embodiment, protrusions 2 at the protrusion forming regions 5 contribute to the improvement in the stability against inclination of the golf bag in the front-rear direction and contribute to the prevention of rotation, while auxiliary protrusions 3 are responsible for the improvement of the stability in the lateral direction. In order to make each pair of tangents 11 drawn from the protrusion in the front-rear direction and each pair of tangents 12 drawn from the protrusion in the lateral direction pass outside of the base peripheral edge 6 when just one protrusion is formed at each of the protrusion forming region as shown in the embodiment of
In this case, too, it is preferred that the protruding length of the protrusion 2 is from 10 mm or more to 50 mm or less from the base peripheral edge 6. Furthermore, although the position of the auxiliary protrusion 3 is most preferably at 90 degrees and 270 degrees from the reference line, the same effect can be obtained as long as the auxiliary protrusions are the ones that protrude most in the lateral direction.
When an external force acts on a golf bag, inclination may be initiated in a direction other than the front-rear direction or the lateral direction. In such a case, if a tangent 13 linking the adjacent protrusion 2 and auxiliary protrusion 3 intersects with the base peripheral edge 6 with one intersection, or with two intersections, it is thought that the area of the intersection or the area between such two intersections becomes the area that is dynamically unstable, and the golf bag falls after rotating up to the intersection. Accordingly, by making the tangent 13 linking the adjacent protrusion and auxiliary protrusion pass outside of the base peripheral edge 6, stability can be improved further.
To realize such a configuration, the protruding length l of the auxiliary protrusion should be enough if it is at least 8 mm, although it also depends on the length of the protrusion 2.
When playing golf, generally four golf bags are mounted on a golf cart. Taking into consideration the space for bags on a golf cart, in order to mount four golf bags, the protruding length l of the auxiliary protrusions should be kept within 20 mm.
Furthermore, similar stability can be achieved by making all the tangents 14 linking the adjacent protrusions pass outside of the base peripheral edge 6, or by making all the tangents 14 linking the adjacent protrusions and all the tangents 13 linking the adjacent protrusion and auxiliary protrusion pass through outside of the base peripheral edge 6.
In practicing the invention, the protrusions 2 and auxiliary protrusions 3 may be formed integrally with the base, or separately formed protruding parts may be attached to the base 1. If the protrusions 2 and auxiliary protrusions 3 are formed as hollow parts, less weight is added and the bag weight can be reduced.
Referring now in more detail to the drawings,
Since the tangent 13 of the adjacent protrusion 2 and auxiliary protrusion 3 passes outside of the base peripheral edge 6 in the embodiment of
In the above mentioned embodiments, the shape and configuration of the protrusions 2 and auxiliary protrusions 3 are symmetrical. Even if the positions of the protrusions 2 and auxiliary protrusions 3 are irregular, however, similar stability can be achieved by arrangement such that a pair of tangents 11 in the front-rear direction, a pair of tangents 12 in the lateral direction, and tangents 13 of the adjacent protrusion and auxiliary protrusion pass outside of the base peripheral edge 6.
For example,
While the shape of the protrusions 2 and auxiliary protrusions 3 is circular in the embodiments, in order to enhance the rotation preventive effect, they may be formed in any arbitrary shape, including rectangular or elliptical shape, isosceles triangle or scalene triangle, isosceles trapezoid or scalene trapezoid, and other arbitrary polygonal shapes.
As described above, the golf bag of this invention can prevent rotation in such a way that the inclination in the front-rear direction which is apt to occur may not be transferred to a dynamically unstable inclination in the lateral direction, and therefore, the stability of the golf bag is enhanced.
Furthermore, since a tangent drawn between one of the protrusions in the front-rear direction and lateral direction is designed to pass outside of the base peripheral edge, the ability of the golf bag to resist falling caused by an external force can be improved.
Since the stability of the golf bag is improved more than when the diameter of the circular base is merely increased, a golf bag can be produced in a compact design without increasing mass or dimensions. Moreover, the amount of synthetic resin used as a main material of the base can be reduced, minimizing the environmental effects.
Since the bag base of this invention has a rotation preventive function, a bag with this base can be handled and carried stably when mounted on a golf cart or the like.
| Number | Date | Country | Kind |
|---|---|---|---|
| P2001-341296 | Nov 2001 | JP | national |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 10288811 | Nov 2002 | US |
| Child | 11085917 | Mar 2005 | US |
