The present invention relates to a pivotally secured together plier device used to manually restructure and roughen the surface of polyester and synthetic gut tennis strings on a strung tennis racquet. The roughened string surface increases the friction between the string and the tennis ball and thus the player can more easily generate spin on a tennis ball while striking the ball.
Many tennis players try many different techniques to generate spin when they hit the tennis balls. With an ultra-high-speed, 10,000-frame-per-second camera, we can now clearly see how strings generate spin during the 4 or 5 milliseconds when the ball is on the strings. Most spin is generated by main strings (vertical strings) slide and snap back movement after they contact with the tennis ball. Thus, the rougher the main string surface is, the more main string slide and snap back with more power for spin generation, and the easier it is for the player to generate spin. Basically, in order to generate more spin, we need two factors: 1. a rough string/ball contact surface, therefore the strings can grasp the ball better, and the ball can push the main strings to slide more over the cross strings(cross strings); as a result, the main strings can generate more spin when they snap back. 2. a smooth main string/cross string contact surface, therefore the main strings can slide farther over the cross strings and snap back efficiently because of less frictions between the strings, this will give an extra kick to the ball and generate more spin. In order to satisfy two factors stated above, you need a main string that has two different surfaces, rough on the top (where it contacts with the ball) and smooth on the bottom (where it contacts with the cross string) in order to generate spin efficiently.
Most strings are made of synthetic nylon and polyester, and some of them are made of natural gut. Some string manufacturers provide Octagon or Hexagon shaped polyester strings to increase the friction between the string and ball. It may be effective on the main strings when they are new, after some time, the sharp edge of the Octagon and Hexagon will be worn away by wear and tear between the string and ball. As a result, the main strings can no longer grasp and generate spin as effective as when they are new. Some strings come with a series of small dents on the surface to increase the roughness of the string surface. This is effective when it is new, however, after some time, the small dents will be worn off and the string surface becomes smooth again.
The primary objective of this invention is to provide a plier device to mechanically and permanently restructure and roughen the surface of a tennis racquet string, section by section on a strung tennis racquet, by means of mechanical deformation on a string to make friction marks. As a result of this process, the friction between the string and ball will be increased, while the friction between the strings will remain the same. This will allow the main strings slide further over the cross strings, and snap back with more power for spin generation.
In accordance with the present invention, there is provided a plier device comprising a pair of handle levers including a middle portion pivotally secured together with a pivot shaft. Each lever has a handle on one end and a jaw on the other. The plier device is made of steel or another hard material. Only upper jaw has an elevated pattern of closely adjacent line grids or other shapes, such as diamond. They make friction marks on the strings. The lower jaw is smooth and does not make any friction marks on the strings. The end of the lower jaw has an “L” shaped string locker design with a slot in the middle, which allows the bottom jaw to slide beneath a string by rotating the plier handles. On the bottom of bottom jaw, there is also a slot in the middle. This slot allows the lower jaw to be inserted easily between the main and cross tennis strings. Once the upper jaw is above the string and bottom jaw is beneath the string, close the pliers. A series of elevated line grids will then press and reform the string surface and leave a series of indentations on the string without damaging other characteristics of the string. The roughened string surface increases friction between the string and ball, making it easier for the players to generate spin. After some time, if the indentations on the string are worn because of wear and tear, the pliers can be used again to roughen the string. On the upper jaw, there is an adjustment screw and it can be used to adjust the distance of the gap between the upper and bottom jaws, according to various sizes of string diameters. This device solves two common problems for tennis players: 1. Smooth polyester round strings are slippery, they allow the main string to slide and snap back efficiently for spin generation. However, the smooth round strings cannot grasp the ball well. With this device, the string surfaces where they contact the ball can be roughened, and the strings faces between the strings are kept smooth, therefore strings can grasp the ball better for spin generation. 2. Textured/shaped strings can grasp the ball much better than smooth strings, but they become smooth very quickly and no longer effective in spin generation. They are usually cut and replaced before they break. With this device, the string surface can be roughened again, therefore the string performance can be revived.
Referring to
The upper jaw 22 and lower jaw 21 are shown in greater detail in
The lower jaw 21 has 2 elevated L shaped string lockers 23 at the end, which are extruded from upper jaw 22, as indicated on
In
The manner in which the tool of the present invention is used to deform and roughen the surface of the string on a strung racquet is shown in
The same manner can be repeated to put a series of indentations on the rest of the main string 14. The player needs to turn over the racquet and work on the other side of the racquet to complete roughening the string surface. It is not necessary to roughen all the strings on the racquet, it is sufficient to roughen the string in the “sweet spot” on the main strings only, where the string makes contact with the balls most often. This covers about ⅓ the racquet area, in the center. The players can repeat the same process to roughen the cross string 15. Roughening cross string 15 will allow cross string 15 grasp tennis ball better, however, it also increase the friction between main string 14 and cross string 15 and prevent main string 14 from sliding and snapping back efficiently over the cross string 15.
The tool of the present invention is made from any suitable common metal such as steel alloy, aluminum alloy, plastic with high hardness and the like. The handles 10-10 of the tool may preferably be covered with soft material such as plastic or rubber, or the like.
Although a preferred embodiment of the invention has been disclosed for the purpose of illustration, it will be understood that various changes, modifications, and substitutions may be incorporated in such embodiment within the scope of the invention without departing from the spirit of this invention.
This application is a continuation of application Ser. No. 12/833,981 filed on Jul. 10, 2010.
Number | Date | Country | |
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Parent | 12833981 | Jul 2010 | US |
Child | 13355512 | US |