JP2009261914A - Racket frame - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a racket frame having a good control performance, allowing a user to have a good hitting feeling and capable of demonstrating a sufficient control performance even when the ball is hit at an off-center position. <P>SOLUTION: The area of a hitting section 4 is 485 cm<SP>2</SP>or more and less than 550 cm<SP>2</SP>, the length M of a shaft part 6 is within a range of 0.268 or more and 0.352 or less times the overall length L, the length Ma of a throat area 5 is within a range of 0.05-0.147 times the overall length L, the minimum value of the surface outward width SWa is within a range of 12 mm or more and 18 mm or less, the surface inward width SWb of the throat section in the range showing the minimum value of the surface outward width SWa is 0.788 or more and 1.5 or less times the minimum value and (surface outward width YWa in the narrow width section of a yoke section 14)/(surface outward width YWae in the end of the yoke section 14) is 0.36 or more and 0.65 or less. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a racket frame for soft tennis, and more particularly to a “double shaft” structure racket frame having a bifurcated throat region in a shaft portion.

  In tennis competitions, there is a distinction between hard and soft (also called soft) depending on the difference in the balls used, and the required dimensions such as shape and mass of the racket frame used, as well as strength and rigidity are different. It is known. A racket frame for soft tennis (hereinafter referred to as a racket frame) will be described below.

FIG. 10 is a schematic front view showing a conventional racket frame. As shown in FIG. 10, the total length L of this type of racket frame 101 is 680 mm to 710 mm, the mass before the gut is stretched is 170 g to 280 g, and the inertia in the swing direction with the location of 80 mm from the grip end 113 as the rotation axis ^moment, to be within the scope of 21.5g · ^{m 2} ~29.0g · m 2 is typical.

Also, the area of the hitting ball portion 104 varies depending on the player's skill, ability, play style, etc., and the preferred area varies. Usually, a racket frame having a large hitting ball portion 104 area among beginners. As the skill and ability increase, a racket frame with a smaller area of the hitting ball portion 104 tends to be preferred. In general, skill, in between the excellent top-level men's player of the competence, 485cm ² or more 550cm less than ^2, and the women's player of the top level, between the intermediate to advanced level of the player, 550cm ² or more 615cm less than ^2, between Elementary to intermediate-level player, 615 cm ² or more 680 cm less than ^2, between the senior and junior layer, racket frame set in the range of less than 680 cm ² or more 745Cm ² are often used.

Further, the length M of the shaft portion 106 occupying the entire length L of the racket frame 101 is often determined by the relationship with the area of the hit ball portion 104 and the length of the grip portion 107. Usually, when the area of the hitting ball portion 104 is in the range of 485 cm ² or more and less than 550 cm ² , the length M of the shaft portion 106 is 0.268 times to 0.352 times the total length L of the racket frame 101. when the area is in the range of less than 550 cm ² or more 615 cm ^2, the length M of the shaft portion 106 becomes 0.241 times ～0.327 times the total length L, the range area of the hitting portion 104 is less than 615 cm ² or more 680 cm ² The length M is 0.216 to 0.301 times the total length L, and when the area of the hitting ball portion 104 is in the range of 680 cm ² or more and less than 745 cm ² , the length M is 0 of the total length L. .193 times to 0.277 times in many cases.

  Conventionally, as a form of the shaft portion 106, as shown in FIG. 11, a so-called "single shaft" is formed in which a single-shaped shaft portion 106 is formed between the hitting ball portion 104 and the grip portion 107. As shown in FIG. 10, there is a so-called “double shaft” in which a throat region 105 that branches into a bifurcated shape is provided in the shaft portion 106. Here, FIG. 11 is a schematic front view showing a racket frame having a conventional “single shaft” structure.

  In general, the “double shaft” structure racket frame 101 as shown in FIG. 10 is more difficult to twist than the “single shaft” structure racket frame as shown in FIG. Have. For this reason, racket frames with a “double shaft” structure are used not only by beginner-level players with high hitting frequency in off-spot areas, but also among middle- and advanced-level players in recent years as the hitting speed increases and power increases. Has been done.

Usually, in most racket frames having such a “double shaft” structure, the shaft portion 106 is mostly composed of a throat region 105, and as a result, the length of the throat region 105 with respect to the entire length L of the racket frame 101. The ratio of Ma is high. Specifically, when the area of the hitting portion 104 of the racket frame 101 is in the range of 485 cm ² or more and less than 550 cm ² , the length Ma of the throat region 105 is 0.148 times to 0.19 times the total length L of the racket frame 101. When the area of the hitting ball portion 104 is in the range of 550 cm ² or more and less than 615 cm ² , the length Ma of the throat region 105 is 0.134 to 0.18 times the total length L of the racket frame 101. and which, when the area of the hitting portion 104 is in the range of less than 615 cm ² or more 680 cm ^2, the length Ma of the throat region 105 is 0.119 times ～0.17 times the total length L of the racket frame 101, the hitting portion 104 when the area is in the range of less than 680 cm ² or more 745cm ^2, the length Ma of the throat region 105 of the full length L of the racket frame 101 0 Which has a 104-fold to 0.16-fold it is almost.

  By the way, the racket frame 101 having such a “double shaft” structure can obtain a good surface stability performance, but has little bending, so that it takes time to catch the ball by the ball striking surface 103 at the time of striking (ball and ball striking surface 103 Short contact time). For this reason, the racket frame 101 having the “double shaft” structure has a problem that it is difficult to control the hit ball in a normal stroke, service, smash, etc. other than volley, and the shot feel is hard and a good feeling is obtained. It tends to be hard to be caught.

  Therefore, in this type of racket frame 101, for example, the thickness of the outer shell constituting the racket frame 101 is entirely or partially thinned, the type of reinforcing fiber, the elastic modulus, or the orientation angle. Various designs such as the above are designed to give a certain degree of bending. However, it has been difficult to achieve a sufficiently satisfactory bending within the constraint that the design strength required for the racket frame must be ensured.

  Conventionally, in order to improve the deflection of the racket frame, for example, in Patent Document 1, as shown in FIG. 12, in a racket frame 101 having a long racket length L of 710 to 812 mm, a shaft portion 106 with respect to the racket full length L is provided. A racket frame has been proposed in which the ratio of the length M is designed to be small. In the racket frame 101 proposed in this patent document 1, it is said that a favorable bending can be expressed by configuring the length M of the shaft portion 106 occupying the full length L as compared with the conventional racket frame. Here, FIG. 12 is a front view showing another example of a conventional racket frame.

  However, in the conventional racket frame as described above, the length M of the shaft portion 106 with respect to the entire racket length L (in the case of a tennis racket having a double shaft structure) includes a throat region 105 (see FIG. 12) that bifurcates. In order to obtain the above-described ratio, it is necessary to configure the hitting ball portion 104 and the grip portion 107 to be longer, and the hitting ball portion 104 is further increased in size. The grip part 107 tends to be long. And when the hitting ball portion 104 is enlarged in this way, there is a problem that the swing-out performance deteriorates because the mass of the racket frame itself, the moment of inertia, and the wind pressure area at the time of swing increase. It is predicted that it will be difficult to support speedy play. On the other hand, in view of such a problem, if the enlargement of the hitting ball portion 104 is suppressed to some extent, the grip portion 107 must be lengthened accordingly. In this case, there is a problem that the grip portion 107 becomes too long and a sense of incongruity occurs during use.

  Further, in this type of tennis racket, since the racket overall length L is long, the distance from the rotation center of the racket (the grip portion 107 gripped by the player's hand) to the sweet spot becomes long. For this reason, the rate of catching the ball at the sweet spot at the time of hitting decreases, and on the contrary, the frequency at which a good hit can be made tends to decrease.

  In view of such problems, the present inventors have disclosed in Patent Document 2 that the overall length L of the racket frame and the ratio of the length M of the shaft portion to the total length L are substantially the same as those of a conventional general racket frame. We have proposed a racket frame that can exhibit good flexing when hitting, while limiting it within a suitable range.

  The inventor considered the bending behavior of the above-described conventional racket frame. As a result, as shown in FIG. 13, when the ball 111 is hit, the racket frame 101 has a section S <b> 1 from the grip end portion 113 to the bifurcated branching point 110 position of the throat region 105 constituting the shaft portion 106. Since the bending rigidity is high, it hardly bends and exhibits a bending behavior in which the section S2 from the position of the branch point 110 to the tip of the hitting ball portion 104 is bent starting from the position of the branch point 110 (kick point). In the conventional racket frame, since most of the shaft portion 106 is constituted by the throat region 105, the branch point 110 position is in the vicinity of the grip portion 107, and the section S2 that bends starting from the branch point 110 position has a section S2. long. As a result, since the inclination angle (bending angle θ) obtained by bending the section S2 at the time of hitting is reduced, the time for catching the ball 111 by the hitting surface 103 (contact time between the ball 111 and the hitting surface 103) is shortened. It was. Here, FIG. 13 is a schematic diagram for explaining the bending behavior of a conventional racket frame.

  Therefore, the inventor shifts the position of the branch point 110 toward the hitting ball portion 104 and configures the section S2 that is bent starting from the branch point 110, that is, the throat region 105 occupying the length M of the shaft portion 106. A racket frame in which the ratio of the length Ma is small is proposed (see, for example, Patent Document 2). According to the racket frame proposed in Patent Document 2, it is possible to increase the bending angle θ of the section that is bent at the time of hitting, and therefore the time for catching the ball 111 by the hitting surface 103 (contact between the ball 111 and the hitting surface 103) Time) can be lengthened, and good control performance and feel at impact can be obtained at the time of impact.

Japanese Patent No. 2866020 JP 2004-97303 A

  The inventor has further studied, and in the racket frame as shown in Patent Document 2, there is room for further improvement in the ball control characteristics when the ball 111 is hit at the off-center position of the hitting surface 103. I found out. That is, in the racket frame disclosed in Patent Document 2, the bending direction of the racket frame is a horizontal axis with respect to the racket frame (an axis extending in a direction perpendicular to the extending direction of the grip portion 107). It becomes the direction. That is, the degree of bending with the center of rotation of the vertical axis of the racket frame (the axis extending in the in-plane direction and extending in the extending direction of the grip portion 107) is not so large. Therefore, when the ball 111 is hit at the off-center position of the hitting surface 103, the contact time between the ball and the gut of the hitting surface 103 is shortened, and there is a problem that the control performance of the ball is insufficient.

  Also, in recent play, many hitting balls (top hitting) at high hitting points before and after the base line are seen, and as a result, the hitting surface 103 of the racket enters obliquely with respect to the traveling direction of the ball 111. It is increasing. In this case, in the conventional racket frame, the rigidity in the in-plane direction at the throat region 105 is insufficient, so that the racket is low in stability, and as a result, there is a high possibility of a miss shot.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to obtain a good control performance and a feeling of hitting the ball, and to provide a ball at an off-center position on the hitting surface. It is to provide a racket frame that exhibits sufficient control performance even when hitting and shows high stability even in situations such as top hitting.

A racket frame according to the present invention is a racket frame that includes a hitting ball portion, a shaft portion, and a grip portion, and has a throat region in which the shaft portion branches into a bifurcated shape. L is 680 mm or more and 710 mm or less. The area of the hit ball portion is set within a range of 485 cm ² or more and less than 550 cm ² . The length M of the shaft portion is set in the range of 0.268 times or more and 0.352 times or less of the total length L. The length Ma of the throat region is set within a range of 0.05 times or more and 0.147 times or less of the total length L. The minimum value of the out-of-plane width SWa in the pair of left and right throat portions constituting the throat region is 12 mm or more and 18 mm or less. The in-plane direction width SWb of the throat portion in the region showing the minimum value of the out-of-plane direction width SWa is set within the range of 0.788 times to 1.5 times the minimum value. A pair of left and right throat portions are connected to each other at the upper end side of the throat region, and a yoke portion constituting a part of the hitting ball portion has a narrow width portion where the width in the out-of-plane direction is the narrowest. The ratio of YWae to YWa (YWa), where YWa is the width in the out-of-plane direction at the narrow part of the yoke part, and YWae is the width in the out-of-plane direction at the end of the yoke part in the region where the yoke part is connected to the throat part. / YWae) is set in a range of 0.36 to 0.65.

A racket frame according to the present invention is a racket frame that includes a hitting ball portion, a shaft portion, and a grip portion, and has a throat region in which the shaft portion branches into a bifurcated shape. L is 680 mm or more and 710 mm or less. The area of the hit ball portion is set within a range of 550 cm ² or more and less than 615 cm ² . The length M of the shaft portion is set within the range of 0.241 times or more and 0.327 times or less of the total length L. The length Ma of the throat region is set within a range of 0.05 times or more and 0.133 times or less of the total length L. The minimum value of the out-of-plane width SWa in the pair of left and right throat portions constituting the throat region is 12 mm or more and 18 mm or less. The in-plane direction width SWb of the throat portion in the region showing the minimum value of the out-of-plane direction width SWa is set within the range of 0.788 times to 1.5 times the minimum value. A pair of left and right throat portions are connected to each other at the upper end side of the throat region, and a yoke portion constituting a part of the hitting ball portion has a narrow width portion where the width in the out-of-plane direction is the narrowest. The ratio of YWae to YWa (YWa), where YWa is the width in the out-of-plane direction at the narrow part of the yoke part, and YWae is the width in the out-of-plane direction at the end of the yoke part in the region where the yoke part is connected to the throat part. / YWae) is set in a range of 0.36 to 0.65.

A racket frame according to the present invention is a racket frame that includes a hitting ball portion, a shaft portion, and a grip portion, and has a throat region in which the shaft portion branches in a bifurcated shape. The total length L is 680 mm or more and 710 mm or less. Area of the hitting portion is set in the range of less than 615 cm ² or more 680 cm ^2. The length M of the shaft portion is set within the range of 0.216 times or more and 0.301 times or less of the total length L. The length Ma of the throat region is set within a range of 0.05 times or more and 0.118 times or less of the total length L. The minimum value of the out-of-plane width SWa in the pair of left and right throat portions constituting the throat region is 14 mm or more and 20 mm or less. The in-plane direction width SWb of the throat portion in the region showing the minimum value of the out-of-plane direction width SWa is set within the range of 0.788 times to 1.5 times the minimum value. A pair of left and right throat portions are connected to each other at the upper end side of the throat region, and a yoke portion constituting a part of the hitting ball portion has a narrow width portion where the width in the out-of-plane direction is the narrowest. The ratio of YWae to YWa (YWa), where YWa is the width in the out-of-plane direction at the narrow part of the yoke part, and YWae is the width in the out-of-plane direction at the end of the yoke part in the region where the yoke part is connected to the throat part. / YWae) is set in a range of 0.36 to 0.65.

A racket frame according to the present invention is a racket frame that includes a hitting ball portion, a shaft portion, and a grip portion, and has a throat region in which the shaft portion branches into a bifurcated shape. L is 680 mm or more and 710 mm or less. The area of the hit ball portion is set within a range of 680 cm ² or more and less than 745 cm ² . The length M of the shaft portion is set in a range of 0.193 times or more and 0.277 times or less of the total length L. The length Ma of the throat region is set within a range of 0.05 times or more and 0.103 times or less of the total length L. The minimum value of the out-of-plane width SWa in the pair of left and right throat portions constituting the throat region is 14 mm or more and 20 mm or less. The in-plane direction width SWb of the throat portion in the region showing the minimum value of the out-of-plane direction width SWa is set within the range of 0.788 times to 1.5 times the minimum value. A pair of left and right throat portions are connected to each other at the upper end side of the throat region, and a yoke portion constituting a part of the hitting ball portion has a narrow width portion where the width in the out-of-plane direction is the narrowest. The ratio of YWae to YWa (YWa), where YWa is the width in the out-of-plane direction at the narrow part of the yoke part, and YWae is the width in the out-of-plane direction at the end of the yoke part in the region where the yoke part is connected to the throat part. / YWae) is set in a range of 0.36 to 0.65.

  In the racket frame, even if the out-of-plane width YWa in the narrow portion of the yoke portion is set within a range of 0.5 to 0.88 times the in-plane width SWb in the throat portion. Good.

A racket frame according to the present invention is a racket frame that includes a hitting ball portion, a shaft portion, and a grip portion, and has a throat region in which the shaft portion branches into a bifurcated shape. L is 680 mm or more and 710 mm or less. The area of the hit ball portion is set within a range of 485 cm ² or more and less than 550 cm ² . The length M of the shaft portion is set in the range of 0.268 times or more and 0.352 times or less of the total length L. The length Ma of the throat region is set within a range of 0.05 times or more and 0.147 times or less of the total length L. The minimum value of the out-of-plane width SWa in the pair of left and right throat portions constituting the throat region is 12 mm or more and 18 mm or less. The in-plane direction width SWb of the throat portion in the region showing the minimum value of the out-of-plane direction width SWa is set within the range of 0.788 times to 1.5 times the minimum value. A pair of left and right throat portions are connected to each other at the upper end side of the throat region, and a yoke portion constituting a part of the hitting ball portion has a narrow width portion where the width in the out-of-plane direction is the narrowest. The out-of-plane direction width YWa in the narrow width part is set within a range of 0.5 to 0.88 times the in-plane direction width SWb in the throat part.

A racket frame according to the present invention is a racket frame that includes a hitting ball portion, a shaft portion, and a grip portion, and has a throat region in which the shaft portion branches into a bifurcated shape. L is 680 mm or more and 710 mm or less. The area of the hit ball portion is set within a range of 550 cm ² or more and less than 615 cm ² . The length M of the shaft portion is set within the range of 0.241 times or more and 0.327 times or less of the total length L. The length Ma of the throat region is set within a range of 0.05 times or more and 0.133 times or less of the total length L. The minimum value of the out-of-plane width SWa in the pair of left and right throat portions constituting the throat region is 12 mm or more and 18 mm or less. The in-plane direction width SWb of the throat portion in the region showing the minimum value of the out-of-plane direction width SWa is set within the range of 0.788 times to 1.5 times the minimum value. A pair of left and right throat portions are connected to each other at the upper end side of the throat region, and a yoke portion constituting a part of the hitting ball portion has a narrow width portion where the width in the out-of-plane direction is the narrowest. The out-of-plane direction width YWa in the narrow width part is set within a range of 0.5 to 0.88 times the in-plane direction width SWb in the throat part.

A racket frame according to the present invention is a racket frame that includes a hitting ball portion, a shaft portion, and a grip portion, and has a throat region in which the shaft portion branches in a bifurcated shape. The total length L is 680 mm or more and 710 mm or less. Area of the hitting portion is set in the range of less than 615 cm ² or more 680 cm ^2. The length M of the shaft portion is set within the range of 0.216 times or more and 0.301 times or less of the total length L. The length Ma of the throat region is set within a range of 0.05 times or more and 0.118 times or less of the total length L. The minimum value of the out-of-plane width SWa in the pair of left and right throat portions constituting the throat region is 14 mm or more and 20 mm or less. The in-plane direction width SWb of the throat portion in the region showing the minimum value of the out-of-plane direction width SWa is set within the range of 0.788 times to 1.5 times the minimum value. A pair of left and right throat portions are connected to each other at the upper end side of the throat region, and a yoke portion constituting a part of the hitting ball portion has a narrow width portion where the width in the out-of-plane direction is the narrowest. The out-of-plane direction width YWa in the narrow width part is set within a range of 0.5 to 0.88 times the in-plane direction width SWb in the throat part.

A racket frame according to the present invention is a racket frame that includes a hitting ball portion, a shaft portion, and a grip portion, and has a throat region in which the shaft portion branches into a bifurcated shape. L is 680 mm or more and 710 mm or less. The area of the hit ball portion is set within a range of 680 cm ² or more and less than 745 cm ² . The length M of the shaft portion is set in a range of 0.193 times or more and 0.277 times or less of the total length L. The length Ma of the throat region is set within a range of 0.05 times or more and 0.103 times or less of the total length L. The minimum value of the out-of-plane width SWa in the pair of left and right throat portions constituting the throat region is 14 mm or more and 20 mm or less. The in-plane direction width SWb of the throat portion in the region showing the minimum value of the out-of-plane direction width SWa is set within the range of 0.788 times to 1.5 times the minimum value. A pair of left and right throat portions are connected to each other at the upper end side of the throat region, and a yoke portion constituting a part of the hitting ball portion has a narrow width portion where the width in the out-of-plane direction is the narrowest. The out-of-plane direction width YWa in the narrow width part is set within a range of 0.5 to 0.88 times the in-plane direction width SWb in the throat part.

  In this way, by setting the length of the throat area in the above-described range, the bending angle of the section that is bent at the time of hitting can be increased, the time for catching the ball by the hitting surface can be lengthened, and the yoke portion has the above-described length. By forming a narrow portion with an out-of-plane width as shown above, the degree of bending with the vertical axis of the racket frame (the axis extending in the in-plane direction and extending along the extending direction of the grip portion) as the center of rotation is reduced. By increasing the size, it is possible to improve the control performance when the ball is hit at the off-center position. Further, by defining the out-of-plane direction width SWa and the in-plane direction width SWb of the throat portion so as to satisfy the relationship as described above, the rigidity in the in-plane direction in the throat region is improved and the stability of the racket is improved. Can be increased.

  In the racket frame, the ratio of the primary natural frequency in the out-of-plane direction to the primary natural frequency in the in-plane direction may be set to 0.75 or more and 0.95 or less.

  In the racket frame, the primary natural frequency in the in-plane direction may be set within a range of 120 Hz to 150 Hz.

  In the racket frame, the radius of curvature formed by the outer peripheral edge of the throat region projected from the direction orthogonal to the ball striking surface may be set within a range of 30 mm to 210 mm.

  According to the present invention, a racket frame that exhibits sufficient control performance and stability can be realized.

It is a front schematic diagram which shows the racket frame by this invention. It is a cross-sectional schematic diagram in line segment II-II of FIG. It is a cross-sectional schematic diagram in line segment III-III of FIG. It is a cross-sectional schematic diagram which shows the modification of the racket frame shown in FIGS. It is a schematic diagram for demonstrating the bending behavior of the racket frame shown in FIGS. It is an expansion schematic diagram showing the throat area | region of the racket frame shown in FIGS. It is a schematic diagram which shows the structure of the measuring apparatus used for the measurement of the primary bending natural frequency of a racket frame. FIG. 8 is a schematic diagram showing a state of the racket frame when the primary bending natural frequency is measured in the in-plane direction of the racket frame in the measurement apparatus shown in FIG. 7. FIG. 8 is a schematic diagram showing a state of the racket frame when the primary bending natural frequency is measured in the out-of-plane direction of the racket frame in the measurement apparatus shown in FIG. 7. It is a front schematic diagram which shows the conventional racket frame. It is a front schematic diagram which shows the racket frame of the conventional "single shaft" structure. It is a front view which shows the other example of the conventional racket frame. It is a schematic diagram for demonstrating the bending behavior of the conventional racket frame.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following drawings, the same or corresponding parts are denoted by the same reference numerals, and description thereof will not be repeated.

An embodiment of a racket frame according to the present invention will be described with reference to FIGS.
Referring to FIGS. 1 to 3, the racket frame 1 includes a hitting ball portion 4 in which a gut 2 is stretched to form a hitting ball surface 3, and a throat region 5 branched into a bifurcated shape and connected to the hitting ball portion 4. The shaft portion 6 has a grip portion 7. The overall length L of the racket frame 1 and the length M of the shaft portion 6 are substantially the same as those of a conventional general racket frame. The overall length L is 680 mm or more and 710 mm or less, and the length M of the shaft portion 6 is The total length L is set within the range of 0.193 times or more and 0.352 times or less.

  And in the racket frame 1, the length Ma of the throat area | region 5 which comprises the shaft part 6 is comprised short, and the ratio of the length Ma of the throat area | region 5 which occupies for the full length L is designed smaller than the conventional racket frame. .

That is, the length M of the shaft portion 6 and the length Ma of the throat region 5 set in the racket frame 1 shown in FIGS. 1 to 3 are the area of the hitting portion 4 constituting the racket frame 1 as described above. Depending on the difference, the preferred length varies. Regarding the characteristic configuration of the racket frame 1 according to the embodiment of the present invention, such as the length M of the shaft portion 6 and the length Ma of the throat region 5, requirements such as a suitable size for each area of each hitting ball portion 4 When the area of the hit ball portion 4 is in the range of 485 cm ² or more and less than 550 cm ² , the length Ma of the throat region is set in the range of 0.05 to 0.147 times the full length L. . As shown in FIG. 2, the minimum value of the out-of-plane direction width SWa in the pair of left and right throat portions 6 constituting the throat region is 12 mm or more and 18 mm or less, more preferably 14 mm or more and 16 mm or less. The in-plane direction width SWb of the throat portion 6 in the region showing the minimum value of the out-of-plane direction width SWa is 0.788 times to 1.5 times, more preferably 0.83 times to 1. It is set within a range of 13 times or less. The yoke part 14 which connects a pair of left and right throat parts on the upper end side of the throat area 5 and constitutes a part of the hitting ball part 4 has a narrow width part where the width in the out-of-plane direction is the narrowest as shown in FIG. 17. When the width in the out-of-plane direction of the narrow width portion 17 of the yoke portion 14 is YWa and the width in the out-of-plane direction YWae (see FIG. 3) of the end portion of the yoke portion in the region where the yoke portion 14 is connected to the throat portion 6 The ratio of YWae to YWa (YWa / YWae) is set in the range of 0.36 to 0.65, more preferably 0.45 to 0.60. The out-of-plane width YWa (see FIG. 3) in the narrow width portion 17 of the yoke portion 14 is 0.5 to 0.88 times, more preferably 0.5 times, the in-plane width SWb of the throat region frame 15. It is set within the range of 0.63 times or less.

Further, when the area of the hitting ball portion 4 is in the range of 550 cm ² or more and less than 615 cm ² , the length Ma of the throat region is set in the range of 0.05 times or more and 0.133 times or less of the total length L. As shown in FIG. 2, the minimum value of the out-of-plane direction width SWa in the pair of left and right throat portions constituting the throat region is 12 mm or more and 18 mm or less, more preferably 14 mm or more and 16 mm or less. The in-plane direction width SWb of the throat portion in the region showing the minimum value of the out-of-plane direction width SWa is 0.788 times to 1.5 times, more preferably 0.83 times to 1.13 times the minimum value. It is set within the range of double or less. The yoke part 14 which connects a pair of left and right throat parts on the upper end side of the throat area 5 and constitutes a part of the hitting ball part 4 has a narrow width part where the width in the out-of-plane direction is the narrowest as shown in FIG. 17. When the width in the out-of-plane direction of the narrow width portion 17 of the yoke portion 14 is YWa and the width in the out-of-plane direction YWae (see FIG. 3) of the end portion of the yoke portion in the region where the yoke portion 14 is connected to the throat portion 6 The ratio of YWae to YWa (YWa / YWae) is set in the range of 0.36 to 0.65, more preferably in the range of 0.45 to 0.60. The out-of-plane width YWa (see FIG. 3) in the narrow width portion 17 of the yoke portion 14 is 0.5 to 0.88 times, more preferably 0.5 times, the in-plane width SWb of the throat region frame 15. It is set within the range of 0.63 times or less.

When the area of the hitting portion 4 is in the range of less than 615 cm ² or more 680 cm ^2, the length Ma of the throat region is set within 0.301 times the range 0.216 times the total length L. As shown in FIG. 2, the minimum value of the out-of-plane width SWa in the pair of left and right throat portions 6 constituting the throat region is 14 mm or more and 20 mm or less, more preferably 16 mm or more and 18 mm or less. The in-plane direction width SWb of the throat portion in the region showing the minimum value of the out-of-plane direction width SWa is 0.788 times to 1.5 times, more preferably 0.83 times to 1.13 times the minimum value. It is set within the range of double or less. The yoke part 14 which connects a pair of left and right throat parts on the upper end side of the throat area 5 and constitutes a part of the hitting ball part 4 has a narrow width part where the width in the out-of-plane direction is the narrowest as shown in FIG. 17. When the width in the out-of-plane direction of the narrow-width portion 17 of the yoke portion is YWa and the width in the out-of-plane direction YWae (see FIG. 2) of the end of the yoke portion in the region where the yoke portion 14 is connected to the throat portion is YWa. The ratio of YWae to YWae (YWa / YWae) is set in the range of 0.36 to 0.65, more preferably 0.45 to 0.60. The out-of-plane width YWa (see FIG. 3) in the narrow width portion 17 of the yoke portion 14 is 0.5 to 0.88 times, more preferably 0.5 times, the in-plane width SWb of the throat region frame 15. It is set within the range of 0.63 times or less.

When the area of the hitting ball portion 4 is in a range of 680 cm ² or more and less than 745 cm ² , the length Ma of the throat region is set in a range of 0.193 times or more and 0.277 times or less of the total length L. As shown in FIG. 2, the minimum value of the out-of-plane width SWa in the pair of left and right throat portions 6 constituting the throat region is 14 mm or more and 20 mm or less, more preferably 16 mm or more and 18 mm or less. The in-plane direction width SWb of the throat portion in the region showing the minimum value of the out-of-plane direction width SWa is 0.788 times to 1.5 times, more preferably 0.83 times to 1.13 times the minimum value. It is set within the range of double or less. The yoke part 14 which connects a pair of left and right throat parts on the upper end side of the throat area 5 and constitutes a part of the hitting ball part 4 has a narrow width part where the width in the out-of-plane direction is the narrowest as shown in FIG. 17. When the out-of-plane width in the narrow portion 17 of the yoke portion 14 is YWa, and the out-of-plane width YWae (see FIG. 2) of the end of the yoke portion in the region where the yoke portion 14 is connected to the throat portion, The ratio of YWae to YWa (YWa / YWae) is set in the range of 0.36 to 0.65, more preferably 0.45 to 0.60. The out-of-plane width YWa (see FIG. 3) in the narrow width portion 17 of the yoke portion 14 is 0.5 to 0.88 times, more preferably 0.5 times, the in-plane width SWb of the throat region frame 15. It is set within the range of 0.63 times or less.

  The length M of the shaft portion 6 in the racket frame 1 shown in FIGS. 1 to 3 is the upper end portion of the grip portion 7 from the boundary end portion 8 where the throat region 5 constituting the shaft portion 6 contacts the hitting ball portion 4. Say the length up to 9. Further, the length Ma of the throat region 5 refers to the length from the boundary end 8 to the position of the branch point 10 of the throat region 5 that branches into a bifurcated shape.

  Further, as shown in FIG. 3, the yoke portion 14 has a shape in which the width in the out-of-plane direction of the yoke portion gradually decreases from the end portion of the yoke portion 14 toward the narrow width portion 17 at the center portion (yoke portion 14 The width may gradually change from the out-of-plane direction width YWae at the end portion to the out-of-plane direction width YWa of the narrow-width portion 17, but other configurations may be employed. For example, as shown in FIG. 4, the width in the out-of-plane direction hardly changes from the end portion to the center portion in the yoke portion 14, and the width in the out-of-plane direction decreases relatively rapidly in the center portion, so that the narrow-width portion 17 is formed. It is good also as such a structure. Here, FIG. 4 is a schematic cross-sectional view showing a modification of the racket frame shown in FIGS. FIG. 4 corresponds to FIG.

  In such a racket frame 1, since the overall length L of the racket frame 1 and the length M of the shaft portion 6 are set to substantially the same dimensions as those of a conventional general racket frame, the swing-out performance is deteriorated. There is no problem, and there is no problem that the user feels uncomfortable at the time of use. Furthermore, since the distance from the rotation center of the racket (the grip portion gripped by the player's hand) to the sweet spot does not change, the meet rate of catching the ball at the sweet spot at the time of hitting does not decrease. Therefore, it is easy to handle in actual play with high speed, and stable hitting can be performed.

  In addition, since the ratio of the length Ma of the throat region 5 to the entire length L is designed to be smaller than the conventional racket frame, as shown in FIG. Moves to the hitting ball portion 4 side, and the length of the section S2 which is bent starting from the position of the branch point 10 when the ball is hit is configured to be short. As a result, since the bending angle θ of the section S2 that is bent at the time of hitting can be increased, the time for catching the ball 11 by the hitting surface 3 (contact time between the ball 11 and the hitting surface 3) can be increased, Good control performance and feel at impact can be obtained upon impact. Here, FIG. 5 is a schematic diagram for explaining the bending behavior of the racket frame shown in FIGS.

  Further, as shown in FIGS. 1 and 2, the cross-sectional shape of the throat region frame 15 in the throat region is larger than the conventional one in the ratio of the in-plane direction width SWb to the out-of-plane direction width SWa (the cross-sectional shape of the throat region frame 15). Is made thicker in the in-plane direction), the rigidity in the in-plane direction (the direction indicated by the arrow 16 in FIG. 2) in the throat region 5 of the racket frame 1 is enhanced. For this reason, the stability of the racket can be improved even when the ball is hit at a high hitting point.

  Further, as shown in FIG. 1 and FIG. 3, by forming a narrow portion 17 having a relatively narrow out-of-plane width YWa at the central portion of the yoke portion 14, the vertical axis ( It is easy to generate | occur | produce the bending centering on the rotation center in the in-plane direction and the axis | shaft extended along the extension direction of the grip part 7. FIG. As a result, as shown in FIG. 5, even when the ball 11 a is hit at the off-center position in the hit ball portion 4, the hit ball portion 4 bends with the vertical axis as the rotation center, so that the ball 11 a and the hit ball 3 have a gut. The contact time can be made relatively long, and the control performance of the ball can be improved.

In racquet frame 1 described above, as the upper limit of the length M of the shaft portion 6 above 0.352 times the total length L in the case where the area of the hitting portion 4 is less than 485cm ² or more 550 cm ^2, 550 cm ² or more 615cm 0.327 times of less than ^2, 0.301 times of less than 615 cm ² or more 680 cm ^2, was set to 0.277 times of less than 680 cm ² or more 745Cm ^2, when greater than this, the grip portion This is because 7 becomes too short and uncomfortable when used. The lower limit to the length M of the shaft portion 6 as described above, 0.268 times the total length L in the case where the area of the hitting portion 4 is less than 485cm ² or more 550 cm ^2, in the case of less than 550 cm ² or more 615 cm ² 0.241-fold, 0.216-fold in the case of less than 615 cm ² or more 680 cm ^2, was set to 0.193 times of less than 680 cm ² or more 745Cm ^2, when smaller than this, too grip portion 7 is long This is because the user feels uncomfortable during use.

Further, in the racket frame 1 described above, 0.147 times the total length L of the upper limit of the length Ma of the throat region 5 as described above, the area of the hitting portion 4 is in the case of less than 485cm ² or more 550 cm ^2, 550 cm ² 0.133 times in the case of less than 615 cm ^2, 0.118 times of less than 615 cm ² or more 680 cm ^2, was set to 0.103 times of less than 680 cm ² or more 745Cm ^2, when greater than this, This is because it is difficult to control the hitting ball because the time when the ball 11 is caught by the hitting surface 3 (the contact time of the ball 11 and the hitting surface 3) is shortened because a good deflection angle θ is not obtained at the time of hitting. is there. The lower limit to the length Ma of the throat region 5 as described above, when the area of the hitting portion 4 is less than 485cm ² or more 550 cm ^2, of less than 550 cm ² or more 615 cm ^2, of less than 615 cm ² or more 680 cm ² In the case of 680 cm ² or more and less than 745 cm ² , 0.05 times is set because if it is smaller than this, the hitting ball part 4 is excessively twisted and stable hitting cannot be performed.

Moreover, in the racket frame 1 described above, when the area of the hit ball portion 4 is not less than 485 cm ^{2 and} less than 550 cm ² as described above, the upper limit value of the minimum value of the out-of-plane width SWa in the throat portion (throat region frame 15), and 550 cm ² or more 615 cm ² less 18mm in case, if less than 615 cm ² or more 680 cm ^2, and was set to 20mm in the case of less than 680 cm ² or more 745Cm ^2, if larger than this, good flexure angle when hit This is because the expression of θ cannot be obtained, and the time for catching the ball 11 by the hitting surface 3 (contact time between the ball 11 and the hitting surface 3) is shortened, making it difficult to control the hit ball. The lower limit to the minimum value as described above, when the area of the hitting portion 4 is less than 485cm ² or more 550 cm ^2, and 550 cm ² or more 615 cm ² less 12mm in case, if less than 615 cm ² or more 680 cm ^2, In the case of 680 cm ² or more and less than 745 cm ² , it is set to 14 mm because if it is smaller than this, it is difficult to ensure the durability required for the racket frame (strength required for actual use).

Further, in the racket frame 1 described above, in the plane direction width SWb of the throat area frame 15 the upper limit as described above, the area of the hitting portion 4 of less than 485Cm ² or 550 cm ^2, 550 cm ² or more 615cm less than ² If, in the case of less than 615 cm ² or more 680 cm ^2, was set to 1.5-fold, respectively in the case of less than 680 cm ² or more 745Cm ^2, when greater than this, can not be obtained expression of good flexure angle θ when hit This is because the time for catching the ball 11 by the hitting surface 3 (contact time between the ball 11 and the hitting surface 3) is shortened, and it becomes difficult to control the hitting ball. The lower limit of the in-plane width SWb as described above, when the area of the hitting portion 4 is less than 485cm ² or more 550 cm ^2, of less than 550 cm ² or more 615 cm ^2, of less than 615 cm ² or more 680 cm ^2, 680 cm ^In the case of ² or more and less than 745 cm ^{2, the} ratio is set to 0.788 times, and if it is smaller than this, it is difficult to secure the durability required for the racket frame (strength required for actual use), and the desired surface It becomes difficult to develop inward rigidity and out-of-plane rigidity.

Further, in the racket frame 1 described above, the width in the out-of-plane direction at the narrow width portion 17 of the yoke portion 14 is YWa, and the width in the out-of-plane direction YWae at the end of the yoke portion in the region where the yoke portion 14 is connected to the throat portion. The ratio of YWae to YWa (YWa / YWae
The upper limit of the) as described above, the area of the hitting portion 4 of less than 485cm ² or more 550 cm ^2, of less than 550 cm ² or more 615 cm ^2, of less than 615 cm ² or more 680 cm ^2, 680 cm ² or more 745Cm ² less In each case, the value set to 0.65 is larger than this, and if it is larger than this, it is not possible to obtain a satisfactory deflection angle θ, and the vertical axis of the racket frame at the time of off-center strike (in-plane direction) Since the bend about the rotation center (the axis extending along the extending direction of the grip portion 107) becomes too small, the time for catching the ball 11 by the hitting surface 3 (contact time between the ball 11 and the hitting surface 3) is shortened. This is because it becomes difficult to control the hit ball. The lower limit of the above ratio (YWa / YWae) as described above, the area of the hitting portion 4 of less than 485cm ² or more 550 cm ^2, of less than 550 cm ² or more 615 cm ^2, 615 cm ² or more 680 cm ² less than the In some cases, the reason why the ball hitting portion 4 is set to 0.36 in the case of 680 cm ² or more and less than 745 cm ² is that if it is smaller than this, the hit ball portion 4 is twisted more than necessary, and the surface stability of the hit ball portion is lowered.

  In the racket frame 1 described above, the upper limit of the out-of-plane width YWa of the narrow portion 17 in the yoke portion 14 is 0.88 times the minimum value of the in-plane direction width SWb in the throat region frame 15 as described above. If it is larger than this, it will not be possible to obtain a satisfactory deflection angle θ at the time of hitting, and the vertical axis of the racket frame at the time of off-center hitting (in-plane direction and extension of the grip portion 107) (Axis extending along the direction) becomes the center of rotation and the bending becomes too small. Therefore, the time for catching the ball 11 by the hitting surface 3 (contact time between the ball 11 and the hitting surface 3) is shortened and it is difficult to control the hitting ball. Because it becomes. In addition, the lower limit is set to 0.5 times as described above. If it is smaller than this, it is difficult to secure the strength required for actual use, and the required characteristics (ball feeling, bending, flying, etc.) This is because it is difficult to achieve the above.

  In addition to the above-described configuration, the racket frame 1 shown in FIGS. 1 to 3 is formed with an outer peripheral edge 12 of the throat area 5 projected from a direction orthogonal to the ball striking face 3 as shown in FIG. The radius of curvature R to be set is set in a range of 30 mm or more and 210 m or less, which is smaller than a conventional general racket frame. Thus, when the curvature radius R of the throat region 5 is designed to be small, the flexibility of the throat region 5 is increased, and a good bend can be obtained at the time of hitting, so that a soft shot feeling can be expressed. The radius of curvature R of the throat region 5 is an appropriate range when the length Ma of the throat region 5 is set within the above range, and the upper limit value of the radius of curvature R is set to 210 mm. This is because the flexibility of the throat region 5 becomes poor, and the shot feeling at the time of hitting becomes hard. Further, the lower limit is set to 30 mm because if it is smaller than this, the hitting ball part 4 is more easily twisted than necessary at the time of hitting, and it becomes difficult to perform stable hitting.

  In addition to the above-described configuration, the racket frame 1 shown in FIGS. 1 to 3 has a ratio of the primary natural frequency in the out-of-plane direction to the primary natural frequency in the in-plane direction (primary bending natural frequency). (Primary natural frequency in out-of-plane direction / primary natural frequency in in-plane direction) is set to 0.75 or more and 0.95 or less. If the ratio exceeds 0.95, the dynamic bending rigidity in the out-of-plane direction becomes too high, and the shot feeling at the time of hitting becomes hard. Further, when the ratio is less than 0.75, the dynamic bending rigidity in the out-of-plane direction becomes too low, and the adverse effect that the flying distance of the hit ball becomes short or stable hitting operation becomes difficult is remarkable. Become. The ratio is preferably 0.80 or more and 0.93 or less, more preferably 0.84 or more and 0.88 or less, and further preferably 0.85 or more and 0.87 or less.

  Moreover, in the racket frame 1 shown in FIGS. 1 to 3, in addition to the above-described configuration, the primary natural frequency (primary bending natural frequency) in the in-plane direction is set within a range of 120 Hz to 150 Hz. is doing. In addition, by setting the primary natural frequency in the in-plane direction within the above range, stable performance suitable as a racket frame is provided. The primary natural frequency in the in-plane direction is particularly preferably set in the range of 125 Hz to 145 Hz, more preferably in the range of 125 Hz to 140 Hz.

  The racket frame of the present invention is preferably composed of a fiber reinforced resin material or a light metal material, and particularly preferably composed of a fiber reinforced resin material. Moreover, when manufacturing the racket flame | frame 1 shown in FIGS. 1-3, for example using fiber reinforced resin, the following processes can be used. For example, first, a plurality of prepreg sheets for forming a racket frame are laminated around a tube for forming an internal pressure. Thereafter, the tube on which the prepreg sheet is laminated is placed in a cavity having a frame shape of a mold. Then, compressed air or the like is injected into the tube and the mold is heated. Thus, the racket frame 1 shown in FIGS. 1 to 3 can be manufactured by a normal manufacturing method of a fiber reinforced resin racket frame.

  Further, as the main reinforcing fiber constituting the racket frame 1 made of fiber reinforced resin, various fibers such as carbon fiber, glass fiber, boron fiber, and aromatic polyamide fiber can be used. However, in terms of strength, rigidity, mass, and cost. Also, it is preferable to use carbon fiber. Moreover, as a matrix resin, although an epoxy resin, a nylon resin, etc. can be used, it is preferable to use an epoxy resin at the point of intensity | strength and durability.

  Further, the mass of the racket frame 1 before the gut is preferably set to 170 g or more and 280 g or less, and particularly preferably 230 g or more and 280 g or less in the case of a racket frame for middle and advanced players. Further, in the case of a racket frame for beginners or less powerful players, it is more preferable that the mass of the racket frame 1 before gut extension is 170 g or more and 230 g or less.

In consideration of the swing-out property, the moment of inertia in the swing direction with the rotation axis at a position 80 mm from the grip end portion 13 of the racket frame 1 is 23.0 g · m in the case of the racket frame 1 for intermediate and advanced players. ² or 29.0 g · ^{m 2} or less, beginner or it is preferable to 21.5 g · ^{m 2} or more 26.0 g · ^{m 2} or less in the case of the racket frame for powerless player.

Example 1
In order to confirm the effect of the present invention, the following actual hit test was conducted.

(sample)
Samples of racket frames of Examples 1 to 5 and Comparative Examples 1 to 14 as shown in Table 1 were prepared. In Examples 1 to 5, the basic configuration is the racket frame configuration shown in FIGS.

(test)
For these racket frames, the primary bending natural frequency (also referred to as primary natural frequency) in the out-of-plane direction and in-plane direction was measured. As a method for measuring the primary bending natural frequency, the following method was specifically used by using the apparatus configuration shown in FIG. With reference to FIG. 7, the measuring method of a primary bending natural frequency is demonstrated.

  As shown in FIG. 7, the apparatus used for the measurement (vibration attenuation measuring apparatus) is a racket frame suspension base 44, a chemical fiber string 45, an impulse hammer 43, an accelerometer 46, and a signal conditioner. 42, an FFT (Fast Fourier Transform) analyzer 41, and a computer 40 as a control device.

  In such an apparatus configuration, the racket frame 1 is first suspended using a string 45 on a racket frame suspension base 44. The string 45 is connected to the grip portion side of the racket frame 1. As a result, the movement of the racket frame 1 in the axial direction (vertical direction in FIG. 7) is mainly restricted, and the racket frame 1 can be moved and rotated almost freely in the other directions. The accelerometer 46 was installed at a position 200 mm from the grip side end of the racket frame 1. The accelerometer 46 is connected to the signal conditioner 42. An impulse hammer 43 for hitting the racket frame 1 is also connected to the signal conditioner 42. The signal conditioner 42 is connected to the computer 40 via the FFT analyzer 41.

  Further, when measuring the primary bending natural frequency in the in-plane direction, as shown in FIG. 8, the direction perpendicular to the grip axis and parallel to the racket surface is applied to the surface of the racket frame 1. An accelerometer 46 is installed. Further, the impact hammer 43 is also struck in the direction indicated by the arrows 47 and 48 in FIG. 8 (the direction perpendicular to the grip axis and parallel to the racket surface). A plurality of hitting positions by the impulse hammer 43 are provided in the axial direction of the racket frame 1.

  When measuring the primary bending natural frequency in the out-of-plane direction, as shown in FIG. 9, the direction perpendicular to the grip axis and from the direction perpendicular to the racket surface is applied to the surface of the racket frame 1. An accelerometer 46 is installed. Further, the impact hammer 43 is also struck from the direction indicated by the arrow 49 in FIG. 9 (the direction perpendicular to the grip axis and perpendicular to the racket surface). In addition, the impact position by the impulse hammer 43 is provided at a plurality of positions in the axial direction of the racket frame 1 as in the case shown in FIG. In any case, no hitting position is provided in the grip portion.

In such an apparatus configuration, the measurement was performed as follows.
First, a predetermined hitting position of the racket frame 1 is hit by the impulse hammer 43. Then, the time-dependent change in vibration (deformation) of the racket frame 1 due to this impact is measured by the accelerometer 46 as time-series data. Then, the natural frequency was measured by analyzing the measurement result with the FFT analyzer 41. The measurement result is displayed / recorded on the computer 40.

  Here, for the impulse hammer 43, the accelerometer 46, the signal conditioner 42, and the TFT analyzer 41, PCB PIEZOTRICS. INC. 208A04, PCB PIEZOTRONICS. INC. Model 352A21, PCB PIEZOTRONICS. INC. No. Model 483A and Ono Sokki Co., Ltd. Model DS-9110 were used.

  Further, an actual hitting test was performed on the racket frame. In this actual hit test, a plurality of (20 players) middle / advanced players (high school, university, member of society) are actually used in actual battles using the racket frames of Examples 1 to 5 and Comparative Examples 1 to 14. The game-style batting practice was conducted according to the above, and the controllability, surface stability, feel at impact, etc. experienced by the players were evaluated. In particular, the control performance at the time of hitting at an off-center position and the stability of the racket at the time of hitting a ball at a high hitting point were evaluated as independent items. The results of the test described above are shown in the following table.

  (result)

  Table 2 is a table showing the measurement result of the primary bending natural frequency and the calculation result of the frequency ratio (primary bending natural frequency in the out-of-plane direction / primary bending natural frequency in the in-plane direction) described above. As can be seen from Table 2, in Examples 1 to 5, the frequency ratio is within the numerical range of 0.84 to 0.93, and the primary bending natural frequency in the in-plane direction is 124 Hz to 130 Hz. It is in the following numerical range. On the other hand, in the samples of Comparative Examples 1 to 14, the frequency ratio is almost a value of 1, and the primary bending natural frequency in the in-plane direction is almost 120 Hz or less.

  Table 3 is a table that closes the results of the actual hit test described above. As can be seen from Table 3, each of Examples 1 to 5 obtained good evaluation in each item. On the other hand, as for Comparative Examples 1 to 14, some of the individual items obtained partially good evaluation, but particularly when the ball was hit at a high hitting point and the control performance at the time of hitting at an off-center position. The stability of the racket was low.

  It should be understood that the embodiments and examples disclosed herein are illustrative and non-restrictive in every respect. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  The present invention is advantageously applied to a racket frame for soft tennis having a double shaft structure.

  1,101 racket frame, 2 guts, 3,103 hitting ball surface, 4,104 hitting ball part, 5,105 throat area, 6,106 shaft part, 7,107 grip part, 8 boundary edge part, 9 upper edge part, 10, 110 branch point, 11, 11a, 111 ball, 12 outer periphery, 13, 113 grip end part, 14 yoke part, 15 throat area frame, 16, 47-49 arrow, 17 narrow part, 40 computer, 41 FFT analyzer, 42 Signal conditioner, 43 Impulse hammer, 44 Suspension stand, 45 strings, 46 Accelerometer.

Claims (12)

In the racket frame configured by a hitting ball portion, a shaft portion, and a grip portion, and having a throat region where the shaft portion branches in a bifurcated shape,
The overall length L of the racket frame is 680 mm or more and 710 mm or less,
The area of the hitting ball portion is set within a range of 485 cm ² or more and less than 550 cm ² ;
The length M of the shaft portion is set within a range of 0.268 times or more and 0.352 times or less of the total length L,
The length Ma of the throat region is set within a range of 0.05 times or more and 0.147 times or less of the total length L,
The minimum value of the out-of-plane direction width SWa in the pair of left and right throat portions constituting the throat region is in the range of 12 mm or more and 18 mm or less,
The in-plane direction width SWb of the throat portion in the region indicating the minimum value of the out-of-plane direction width SWa is set to be not less than 0.788 times and not more than 1.5 times the minimum value,
The yoke part that connects the pair of left and right throat parts on the upper end side of the throat region and constitutes a part of the hitting ball part has a narrow part in which the width in the out-of-plane direction is the narrowest,
The ratio of YWae to YWa (YWa), where YWa is the width in the out-of-plane direction at the narrow part of the yoke part, and YWae is the width in the out-of-plane direction at the end of the yoke part in the region where the yoke part is connected to the throat part. / YWae) is a racket frame set in a range of 0.36 to 0.65. In the racket frame configured by a hitting ball portion, a shaft portion, and a grip portion, and having a throat region where the shaft portion branches in a bifurcated shape,
The overall length L of the racket frame is 680 mm or more and 710 mm or less,
The area of the hitting portion is set in the range of less than 550 cm ² or more 615 cm ^2,
The length M of the shaft portion is set within a range of 0.241 times or more and 0.327 times or less of the total length L,
The length Ma of the throat region is set within a range of 0.05 times or more and 0.133 times or less of the total length L,
The minimum value of the out-of-plane direction width SWa in the pair of left and right throat portions constituting the throat region is in the range of 12 mm or more and 18 mm or less,
The in-plane direction width SWb of the throat portion in the region indicating the minimum value of the out-of-plane direction width SWa is set to be not less than 0.788 times and not more than 1.5 times the minimum value,
The yoke part that connects the pair of left and right throat parts on the upper end side of the throat region and constitutes a part of the hitting ball part has a narrow part in which the width in the out-of-plane direction is the narrowest,
The ratio of YWae to YWa (YWa), where YWa is the width in the out-of-plane direction at the narrow part of the yoke part, and YWae is the width in the out-of-plane direction at the end of the yoke part in the region where the yoke part is connected to the throat part. / YWae) is a racket frame set in a range of 0.36 to 0.65. In the racket frame configured by a hitting ball portion, a shaft portion, and a grip portion, and having a throat region where the shaft portion branches in a bifurcated shape,
The overall length L of the racket frame is 680 mm or more and 710 mm or less,
The area of the hitting portion is set in the range of less than 615 cm ² or more 680 cm ^2,
The length M of the shaft portion is set within a range of 0.216 times to 0.301 times the total length L,
The length Ma of the throat region is set within a range of 0.05 times or more and 0.118 times or less of the total length L,
The minimum value of the out-of-plane direction width SWa in the pair of left and right throat portions constituting the throat region is in the range of 14 mm or more and 20 mm or less,
The in-plane direction width SWb of the throat portion in the region indicating the minimum value of the out-of-plane direction width SWa is set to be not less than 0.788 times and not more than 1.5 times the minimum value,
The yoke part that connects the pair of left and right throat parts on the upper end side of the throat region and constitutes a part of the hitting ball part has a narrow part in which the width in the out-of-plane direction is the narrowest,
The ratio of YWae to YWa (YWa), where YWa is the width in the out-of-plane direction at the narrow part of the yoke part, and YWae is the width in the out-of-plane direction at the end of the yoke part in the region where the yoke part is connected to the throat part. / YWae) is a racket frame set in a range of 0.36 to 0.65. In the racket frame configured by a hitting ball portion, a shaft portion, and a grip portion, and having a throat region where the shaft portion branches in a bifurcated shape,
The overall length L of the racket frame is 680 mm or more and 710 mm or less,
The area of the hit ball portion is set within a range of 680 cm ² or more and less than 745 cm ² ,
The length M of the shaft portion is set within a range of 0.193 times or more and 0.277 times or less of the total length L,
The length Ma of the throat region is set within a range of 0.05 times or more and 0.103 times or less of the total length L,
The minimum value of the out-of-plane direction width SWa in the pair of left and right throat portions constituting the throat region is in the range of 14 mm or more and 20 mm or less,
The in-plane direction width SWb of the throat portion in the region indicating the minimum value of the out-of-plane direction width SWa is set to be not less than 0.788 times and not more than 1.5 times the minimum value,
The yoke part that connects the pair of left and right throat parts on the upper end side of the throat region and constitutes a part of the hitting ball part has a narrow part in which the width in the out-of-plane direction is the narrowest,
The ratio of YWae to YWa (YWa), where YWa is the width in the out-of-plane direction at the narrow part of the yoke part, and YWae is the width in the out-of-plane direction at the end of the yoke part in the region where the yoke part is connected to the throat part. / YWae) is a racket frame set in a range of 0.36 to 0.65.   The out-of-plane direction width YWa in the narrow part of the yoke part is set within a range of 0.5 to 0.88 times the in-plane direction width SWb in the throat part. The racket frame of any one of Claims 1-4. In the racket frame configured by a hitting ball portion, a shaft portion, and a grip portion, and having a throat region where the shaft portion branches in a bifurcated shape,
The overall length L of the racket frame is 680 mm or more and 710 mm or less,
The area of the hitting ball portion is set within a range of 485 cm ² or more and less than 550 cm ² ;
The length M of the shaft portion is set within a range of 0.268 times or more and 0.352 times or less of the total length L,
The length Ma of the throat region is set within a range of 0.05 times or more and 0.147 times or less of the total length L,
The minimum value of the out-of-plane direction width SWa in the pair of left and right throat portions constituting the throat region is in the range of 12 mm or more and 18 mm or less,
The in-plane direction width SWb of the throat portion in the region indicating the minimum value of the out-of-plane direction width SWa is set to be not less than 0.788 times and not more than 1.5 times the minimum value,
The yoke part that connects the pair of left and right throat parts on the upper end side of the throat region and constitutes a part of the hitting ball part has a narrow part in which the width in the out-of-plane direction is the narrowest,
The racket frame in which the out-of-plane direction width YWa in the narrow width part is set within a range of 0.5 to 0.88 times the in-plane direction width SWb in the throat part. In the racket frame configured by a hitting ball portion, a shaft portion, and a grip portion, and having a throat region where the shaft portion branches in a bifurcated shape,
The overall length L of the racket frame is 680 mm or more and 710 mm or less,
The area of the hitting portion is set in the range of less than 550 cm ² or more 615 cm ^2,
The length M of the shaft portion is set within a range of 0.241 times or more and 0.327 times or less of the total length L,
The length Ma of the throat region is set within a range of 0.05 times or more and 0.133 times or less of the total length L,
The minimum value of the out-of-plane direction width SWa in the pair of left and right throat portions constituting the throat region is in the range of 12 mm or more and 18 mm or less,
The in-plane direction width SWb of the throat portion in the region indicating the minimum value of the out-of-plane direction width SWa is set to be not less than 0.788 times and not more than 1.5 times the minimum value,
The yoke part that connects the pair of left and right throat parts on the upper end side of the throat region and constitutes a part of the hitting ball part has a narrow part in which the width in the out-of-plane direction is the narrowest,
The racket frame in which the out-of-plane direction width YWa in the narrow width part is set within a range of 0.5 to 0.88 times the in-plane direction width SWb in the throat part. In the racket frame configured by a hitting ball portion, a shaft portion, and a grip portion, and having a throat region where the shaft portion branches in a bifurcated shape,
The overall length L of the racket frame is 680 mm or more and 710 mm or less,
The area of the hitting portion is set in the range of less than 615 cm ² or more 680 cm ^2,
The length M of the shaft portion is set within a range of 0.216 times to 0.301 times the total length L,
The length Ma of the throat region is set within a range of 0.05 times or more and 0.118 times or less of the total length L,
The minimum value of the out-of-plane direction width SWa in the pair of left and right throat portions constituting the throat region is in the range of 14 mm or more and 20 mm or less,
The in-plane direction width SWb of the throat portion in the region indicating the minimum value of the out-of-plane direction width SWa is set to be not less than 0.788 times and not more than 1.5 times the minimum value,
The yoke part that connects the pair of left and right throat parts on the upper end side of the throat region and constitutes a part of the hitting ball part has a narrow part in which the width in the out-of-plane direction is the narrowest,
The racket frame in which the out-of-plane direction width YWa in the narrow width part is set within a range of 0.5 to 0.88 times the in-plane direction width SWb in the throat part. In the racket frame configured by a hitting ball portion, a shaft portion, and a grip portion, and having a throat region where the shaft portion branches in a bifurcated shape,
The overall length L of the racket frame is 680 mm or more and 710 mm or less,
The area of the hit ball portion is set within a range of 680 cm ² or more and less than 745 cm ² ,
The length M of the shaft portion is set within a range of 0.193 times or more and 0.277 times or less of the total length L,
The length Ma of the throat region is set within a range of 0.05 times or more and 0.103 times or less of the total length L,
The minimum value of the out-of-plane direction width SWa in the pair of left and right throat portions constituting the throat region is in the range of 14 mm or more and 20 mm or less,
The in-plane direction width SWb of the throat portion in the region indicating the minimum value of the out-of-plane direction width SWa is set to be not less than 0.788 times and not more than 1.5 times the minimum value,
The yoke part that connects the pair of left and right throat parts on the upper end side of the throat region and constitutes a part of the hitting ball part has a narrow part in which the width in the out-of-plane direction is the narrowest,
The racket frame in which the out-of-plane direction width YWa in the narrow width part is set within a range of 0.5 to 0.88 times the in-plane direction width SWb in the throat part.   10. The ratio of the primary natural frequency in the out-of-plane direction to the primary natural frequency in the in-plane direction is set to 0.75 or more and 0.95 or less, according to claim 1. Racket frame.   The racket frame according to claim 10, wherein the primary natural frequency in the in-plane direction is set in a range of 120 Hz to 150 Hz.   The radius of curvature formed by the outer peripheral edge of the throat region projected from a direction orthogonal to the ball striking surface is set in a range of 30 mm or more and 210 mm or less. Racket frame.

Images