JPH069664U - tennis racket - Google Patents

Abstract

(57) [Abstract] [Purpose] A racket that is thick and highly repulsive, and a racket that is light and has good operability, realizes the contradictory advantages of the currently popular rackets with a single racket, and at the same time, arm by impact. A racket that is lighter in weight, thicker, more repulsive and has better operability. [Structure] A top portion and a shaft portion of the gut stretched portion are thickest, and a shock absorbing material is applied to the top portion.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 This invention provides optimum rigidity, maneuverability, and repulsion to a weak player such as a woman by specifying the weight, center of gravity position, natural frequency, and thickness of each part of the racket. About the tennis racket that did.

[0002]

[Prior art]

 Generally, a racket having a thickened part of the frame (hereinafter referred to as "thick racket") is made by thickening a part or the whole of the frame in a direction perpendicular to the gut plane, and thereby a cross section relating to the bending of the racket. The secondary moment (hereinafter referred to as "section secondary moment") is made large to increase the bending rigidity in the direction perpendicular to the gut plane. As a result, the racket's vibration frequency becomes high, and the repulsion is good and the speed of the hit ball is increased, so it is becoming a popular general player. In addition, a racket that is lightweight and has a center of gravity closer to the top (hereinafter referred to as "top snake") (hereinafter referred to as "tonkachi racke") has good operability and is easy to swing out.

[0003]

[Problems to be solved by the present invention]

 The players using the above-mentioned thick racket and tonkachi racket have contradictory problems and common problems. For example, thick racket has high repulsion but poor operability, while Tonkachi racket has good operability but repulsion is normal. Therefore, both have the common drawback that the impact at the time of impact is large and the burden on the arm is large. Therefore, it is ideal if both can be combined into a single racket. However, the thicker the frame, the higher the rigidity, but also the weight, and the lighter the operability, the worse the repulsion.

[0004]

[Means to solve the problem]

 In order to solve the above problems, the present invention focused on a method of thickening only a part of the frame to effectively increase the rigidity and improve the repulsion with a minimum weight increase. It was found that the part of the racket frame that most affected the bending rigidity was the shaft part, and the other parts did not affect the overall bending rigidity. Next, examining the relationship between repulsion and the center of gravity position, the racket center of gravity position is near the shaft near the grip end from the ball striking surface.Therefore, if the center of gravity position is closer to the top part, the striking position and the center of gravity position will be closer and the repulsion will be better. I found out. Therefore, thicken only the shaft and top of the frame, thin the other parts as much as possible, remove the urethane and the lead for weight adjustment that used to form the grip in the past, and mold it the same as the frame, and the burden on the hand In order to make the weight lighter, a shock absorber is placed only on the top part.

[0005]

[Action]

 By using the above means, it is possible to shift the center of gravity, which was about 31 cm from the conventional grip end, to the top part, without increasing the burden on the hand due to the impact of the conventional manufacturing method, to about 37 cm. It was In addition, it is a negative factor that it is lighter than the conventional racket, but since it is covered by the plus factor that the center of gravity is close to the striking position, it has been possible to improve rigidity and resilience as well as thick racket.

[0006]

【Example】

 To make the center of gravity closer to the top portion 6, the top portion 6 has a maximum thickness of 3 cm, and a vibration absorbing material is interposed between the frame 1 and the bumper. Next, in order to increase the flexural rigidity of the racket and increase the frequency, the shaft portion 3 is also set to the maximum thickness of 3 cm as shown in FIG. The other parts are made as thin as possible to reduce the weight. The center of the gut extension part 2 is the thinnest of a few centimeters, and the grip part 4 has a constant thickness of two and seven centimeters. As shown in FIG. The thick portion and the finest portion are formed in a taper shape, that is, gradually thin or thicker, and the grip portion 3 is integrally molded with the same FRP as the frame 1 to further reduce the weight. With such a shape and structure, the weight of the vibration absorbing material α gel is 255 g and the balance is 37 cm, and the vibration absorbing material α gel is 5 g and the weight is 260 g, the balance is 37 and 5 cm. It became a racket. The primary natural frequency could be realized at about 170 Hz in the freely supported state.

[0007]

[Effect of device]

 Since the present invention is configured as described above, it is lighter than a conventional racket and therefore easy to swing, and optimal operability that the arm is not tired even if the racket is held can be obtained. Also, when hitting, the center of gravity is closer to the top, so you can get the same flight as before without losing the ball. Further, since the optimum rigidity and frequency are obtained, a good shot feeling can be obtained.

[Brief description of drawings]

FIG. 1 is a front view of an embodiment of a tennis racket according to the present invention.

FIG. 2 is a side view showing an embodiment of a tennis racket according to the present invention.

[Explanation of symbols]

 1 Racket frame 2 Gut tension part 3 Shaft part 4 Grip part 5 Yoke part 6 Top part

Claims (3)

[Scope of utility model registration request] 1. The top portion of the gut stretched portion and the shaft portion have approximately the same thickness of 3 cm or more, and the portion of the gut stretched portion excluding the top portion gradually becomes thinner than the top portion and the shaft portion. A tennis racket with a total weight of 300 g or less and a center of gravity of 35 cm or more from the grip end, which is made thin or thick to be tapered. 2. The first natural frequency in the free supporting state is 15
The racket according to claim 1, wherein the racket has a frequency of 0 Hz or higher. 3. The tennis racket according to claim 2, wherein a gap is formed between the top portion of the frame and the bumper, and a vibration absorbing material is interposed there to add an additional weight to the top portion.