JPH0413000Y2 - - Google Patents

Description

[Detailed explanation of the idea]

This invention relates to a golf practice ball made of foamed resin. In the first place, the secret to improving your golf practice is to discover whether your current swing was good or bad when hitting the ball, and if so, which points were bad, and to work on those flaws in your next swing. It means correcting yourself and hitting the ball. For this,
The best way to determine the flaws in your swing is to check the trajectory of the ball you hit and determine the underlying cause of the ball quality. However, this method can only be carried out by using a 250m long hitting practice range, which not only costs a considerable amount of money but also requires traveling to a location far from home, making it difficult to implement. There are some points that you should not practice casually. Therefore, for practice at places other than the hitting field, practice balls are generally used whose purpose is simply to be able to hit the ball accurately without checking the trajectory of the ball. In other words, when practicing at a place other than a golf course, a practical ball that is hit into a basket-shaped net, a sponge ball that imitates the real thing, a styrofoam ball, or
Plastic balls resembling ping-pong balls with more than 20 large holes and other balls with strings are used. As mentioned above, the purpose of using these conventional practice balls is to establish the golfer's own form and thereby practice hitting the club face correctly with the ball, and to judge the quality of the ball hit. In the past, if you wanted something more than that, the only option was to go to a 250m hitting field. Furthermore, regarding individual practice balls in detail, when hitting a practical ball into a stretched net, it often sockets to the outside of the net, which is extremely unsafe.
Also, the trajectory is completely unknown. The sponge ball is
If a stretched net is not used, not only will the ball fly too far and be easily lost, but the surface is too soft, making it difficult for the ball to function effectively, making it impossible to detect changes in the quality of the ball. Plastic ball p shown in Figure 1
Also, the flight distance is quite large and the launch speed is fast, making it difficult to confirm the trajectory.Furthermore, the hole P ₁ and internal cavity P ₂ are so large that the trajectory differs from the actual trajectory, so it is difficult to confirm the trajectory in the cage net. Just like with ball practice, sponge balls, and stringed balls, it becomes just a practice of hitting the ball. In addition, as for conventional foamed polystyrene balls, some are commercially available under the trade name of Plastic Ball P as shown in Figure 1, but they simply imitate the actual product and have a form that is almost exactly like the actual product. It is formed to a diameter of 41.5 mm, which is approximately the same as the small ball (1.62 inches in diameter = 41.1 mm), and the Dainble P ₁ is also approximately 330 mm.
Due to the large number and the material, the depth is shallow, and the effect of Dimble P ₁ is not achieved, so it does not bend to the left or right, and the material is hard and heavy (1.2 g) The ball speed is fast and the flight distance is
This is a very safe situation since the ball is over 9M and the difference between a nice shot and a wrong shot is extremely small, but it only helps in forming the ball's form and cannot judge the quality of the ball. The biggest drawback of this plastic ball P is that the surface of _the ball dents and deforms with each hit, and it does not restore its shape. Not only does the figure disappear, but its overall shape is also deformed and reduced in size. As a result, the trajectory of the ball becomes irregular, making it extremely inaccurate to identify the most important trajectory during practice. This brings about the disadvantage that it becomes difficult to determine exactly what is going on. This idea was created by focusing on the above-mentioned problem, and we selected a slightly elastic and soft type of foamed resin 50 times the size, formed a sphere with a diameter of 44 to 46 mm, and deepened it with a diameter of 5 to 7 mm. Select and engrave 90 to 100 pieces of Dimble according to the dimensions, and reduce the weight to 1 to 100 pieces.
By providing a practice ball with a weight of 0.8g, it is possible to limit the distance it flies, and within that flight distance, it is possible to display a reduced trajectory of the trajectory seen when launching a practical ball. The purpose is to solve these problems. An embodiment of this invention will be described below with reference to FIG. 2 and subsequent figures. First, to describe the configuration with reference to FIG. 2, 1 is a styrofoam sphere with a diameter D of approximately 45 mm, which is about 5% larger than a practical large ball (1.68 inches in diameter = 42.7 mm), and On the surface, the diameter δ of the daimble 2 is expressed as the diameter 3 of the practical ball.
The diameter is 5 to 7 mm, which is larger than 3.5 mm, and the depth is slightly deeper, with approximately 96 pieces evenly engraved. The type of foamed polystyrene is a foamed resin with a specific gravity of 0.02 that is normally used in the industry (it is said to be 50 times higher in the field), that is, a material that weighs 20 kg per ^1M3 and is foamed to a specific gravity of 0.020. Therefore, the ball of this invention weighs approximately 0.85g. The actual value was approximately 0.85g. (4/3 x π x 2.25 ³ x 0.020≒0.95 0.95-0.10=0.85...Reduce the estimated weight of the part removed by the daimble as 0.1g) By the way, the plastic ball P is 30 times as heavy (1M ³
The weight of the material is 33.33Kg, the specific gravity is 0.0333),
Other types of Styrofoam include 8x, 15x, and 40x (the material per ^1M3 is 25x).
kg, specific gravity is 0.025), and there are 60 times as many. The actual weight of the plastic ball P is approximately
It was 1.2g. (Calculated value is 1.245g) Next, the effect will be described. When the practice ball of this invention is hit in windless conditions, it has a reduced trajectory similar to that of a practical ball.
Appears at a maximum flight distance of approximately 6M. In other words, for practical balls, depending on the combination of the direction of the club face at the time of hitting the ball and the trajectory of the club, trajectories corresponding to the codes listed in each column of the table below can be obtained as shown in Figure 3. With this invented practice ball, it appears in a reduced form.

[Table] The above table shows typical examples, but if you further subdivide and combine the direction of the club face and the inclination of the club trajectory, you can achieve the same results as those practiced by professional golfers. A wide variety of trajectories appear. The trajectory also changes depending on the position where the ball hits the club face, but since it would be too complicated, a description of this will be omitted. It goes without saying that the trajectory is a combination of the degree of curvature of the ball shown in the diagram and the degree of rise of the ball, such as liner, tempura, ground ball, socket, etc. Furthermore, in the case of a straight, if you hit it very well with a practical ball, it will extend from the middle, but the practice ball of this invention also has a subtle difference between an ordinary straight and a ball with a good hit that hops even in a straight. The difference is also obvious. In addition, the curve of the batted ball can also be changed to, for example, fade b,
Slices d, large slices f, draws c, hooks e, large hooks g, etc. can also be classified, and it goes without saying that liners, tempura, goro, and sockets can also be separated. Therefore, by looking at these ball lines, you can determine the direction of the club face and the trajectory of the club, and only then can you make corrections and practice intensively. As you get used to the flight distance, you will be able to estimate a distance of 180M or 200M with a practical ball if the distance is like this. As mentioned above, the reason why the reduced trajectory similar to that of a practical ball can be obtained is based on the action of the daimble 2. As is well known, Deimble extends flight distance by eliminating resistance by crushing the air layer that forms in front of the ball as it flies, and also extends flight distance based on the rotation imparted by the shot. This creates a velocity difference in the air flowing on symmetrical surfaces, such as left and right or up and down, creating a differential pressure, which changes the trajectory such as slice, hook, or hop.The practice ball of this invention is extremely lightweight. Since the outer diameter of the ball is large and the ball speed is low, the flight distance will not increase due to air resistance in front of the ball, but differential pressure due to rotation is likely to occur because the ball has a large diameter and the outer diameter of the ball is large. Since the ball 1 itself is lightweight, it is easily moved under the influence of differential pressure, and its trajectory changes from side to side, up and down, and so on. Note that the reason why the weight is limited to 1 g or less is because the differential pressure is extremely small, and the ball cannot be moved in a direction away from its original flight path unless it is lightweight. In addition, the lightweight nature of the ball alleviates the impact of each shot, minimizing deformation and shrinkage, allowing the ball to express the trajectory as accurately as possible, and prolonging the life of the ball. In addition, the reason why the diameter D of the practice ball of this invention is made slightly larger than that of the practical ball is to increase the circumferential speed of the sphere 1 during rotation and to increase the differential pressure.
Reduce ball speed and flight distance to make trajectory identification easier,
In addition, this is to give the impression that the ball is easy to hit during practice, thereby making it easier to hit the ball. Furthermore, the reason why the diameter δ of the daimble 2 is increased to 5 to 7 mm and the depth is slightly deeper is also to facilitate the generation of the pressure difference. The number of engraved pieces was selected to be approximately one-third of that of a practical ball, taking into consideration the strength of the foamed resin.
The number may be set as . If the plastic ball P is engraved with Dimble P ₁ of the same diameter and number as the real thing, it is not only difficult to produce a differential pressure effect, but also the Dimble P ₁ disappears quickly due to the material. The practice ball of this invention takes these points into consideration and is designed to provide the above-mentioned effects. As explained above, this idea uses a foamed resin with an appropriate specific gravity of 0.02, which is 50 times the type, to create a ball with a diameter of 44~44 mm, which is slightly larger than a practical ball.
It is formed into a 46 mm sphere, and on its surface are evenly engraved dimples with a diameter of 5 to 7 mm or more, in a number appropriate to the size, and the weight is 1 to 0.8 g, making it a practical ball. Since the same reduced trajectory can be obtained, it is possible to accurately correct the swing, and not only is it an extremely effective practice method, but it also allows you to experience the fun of actual combat, so you will not get bored for a long time. As a result, you can continue practicing without having to worry about it, resulting in even greater results. In addition, the maximum flight distance is approximately 6 meters, so it is possible to practice hitting the ball in a small area such as an ordinary home's garden, the trajectory is easy to identify, and there is no risk of losing it. Moreover, although it is extremely lightweight, it makes a great sound when struck, and it does not cause any harm to others or damage glass windows or property, making it completely safe. Moreover, the ball has a long lifespan and is inexpensive. Therefore, for example, even parents who feel a little reluctant to let their middle school or high school children go to the practice range can easily recommend it, and on the other hand, children can enjoy a sense of realism just like a real battle. The expansion of usage has been quite significant.

[Brief explanation of the drawing]

FIG. 1 is a front view of a conventional golf practice ball, FIG. 2 is a front view of a ping-pong ball-like plastic ball, FIG. 2 is a front view of a golf practice ball of this invention, FIG. 3 is an explanatory plan view showing the trajectory of a practical golf ball. 1... Sphere, 2... Dimble, D... Diameter of sphere, δ... Diameter of Dimble.

Claims (1)

[Scope of utility model registration request] A deep dimple 90~ with a diameter of 5~7 mm is placed on the surface of a foamed resin sphere with a diameter of 44~46 mm and a specific gravity of 0.02.
100 pieces are evenly engraved, and the weight is 0.8 ~
A golf practice ball that is formed to have a weight of 1g, suppresses flight distance to a maximum of 6M, and is capable of achieving a reduced trajectory similar to that of a practical ball.