Racket

Abstract

A grommet of a racket includes a tubular part. The tubular part includes a through hole through which a string is passed. The through hole includes a base opening, a side wall, and a non-circular tip opening. Assuming an imaginary dividing plane that is perpendicular to a face of the racket and that divides the non-circular tip opening into a first opening portion and a second opening portion shorter than the first opening portion in a direction parallel to the face, an inside dimension of the first opening portion in the direction perpendicular to the face increases gradually from one end of the non-circular tip opening in the direction parallel to the face to the dividing plane. In the tubular part, the string passes through the first opening portion and is in contact with the side wall from the base opening to the tip opening.

What is claimed is: 
     
         1 . A racket comprising:
 a frame;   a grommet mounted on the frame, the grommet including a plurality of tubular parts; and   strings forming a face of the racket, wherein   each of the tubular parts includes a through hole through which a corresponding one of the strings is passed,   the through hole includes a base opening, a side wall, and a tip opening,   at least one of the plurality of tubular parts includes a non-circular tip opening,   assuming an imaginary dividing plane that is perpendicular to the face and that divides the non-circular tip opening into a first opening portion and a second opening portion shorter than the first opening portion in a direction parallel to the face, an inside dimension of the first opening portion in a direction perpendicular to the face increases gradually from one end of the non-circular tip opening in the direction parallel to the face to the dividing plane, and   in the tubular part including the non-circular tip opening, the string passes through the first opening portion and is in contact with the side wall from the base opening to the tip opening.   
     
     
         2 . The racket according to  claim 1 , wherein the first opening portion is generally shaped as a triangle having a vertex at the one end of the non-circular tip opening. 
     
     
         3 . The racket according to  claim 1 , wherein the first opening portion is closer to a centerline of the racket than the second opening portion. 
     
     
         4 . The racket according to  claim 1 , wherein
 the first opening portion includes an edge extending from the one end to the dividing plane, the edge including a straight portion that is straight when viewed in a direction in which the through hole extends, and   a ratio of a length of the straight portion in the direction parallel to the face to a length of the first opening portion in the direction parallel to the face is 0.3 or more.   
     
     
         5 . The racket according to  claim 1 , wherein the string passed through the tubular part including the non-circular tip opening is a longitudinal string. 
     
     
         6 . The racket according to  claim 5 , wherein the tubular part including the non-circular tip opening is located in the vicinity of a top of the frame. 
     
     
         7 . The racket according to  claim 1 , wherein
 the plurality of tubular parts include two or more tubular parts each of which includes the non-circular tip opening, the two or more tubular parts being located in the vicinity of a top of the frame,   edges of the first opening portion of each of the two or more tubular parts include two straight portions each of which is straight when viewed in a direction in which the through hole extends, the two straight portions being symmetrical to each other about a plane parallel to the face,   extensions of the two straight portions in each of the two or more tubular parts form an angle with each other, and   the closer the tubular part is to a centerline of the racket, the smaller the angle between the extensions is.