RACKET FRAME AND RACKET

Abstract

A racket frame includes a frame main body having a loop shape. The frame main body is provided with a plurality of holes, a plurality of main strings extend in an up-down direction and are arranged in a right-left direction and a plurality of cross strings extend in the right-left direction and are arranged in the up-down direction. Through a common hole, out of the plurality of holes, any one of the plurality of main strings and any one of the plurality of cross strings are inserted. A shape of an inner opening of the common hole on an inner peripheral surface of the frame main body is formed such that an opening dimension in a circumferential direction of the frame main body is larger than an opening dimension in a thickness direction of the frame main body.

Claims

1. A racket frame comprising: a frame main body having a loop shape, wherein the frame main body is provided with a plurality of holes, a plurality of main strings extend in an up-down direction and are arranged in a right-left direction, and a plurality of cross strings extend in the right-left direction and are arranged in the up-down direction, the plurality of main strings and the plurality of cross strings arranged to be capable of being extended in a tensioned state inside the frame main body via the plurality of holes, wherein the hole, out of the plurality of holes, through which any one of the plurality of main strings and any one of the plurality of cross strings are inserted is a common hole, and wherein an inner opening shape of the common hole on an inner peripheral surface of the frame main body is formed such that an opening dimension in a circumferential direction of the frame main body is larger than an opening dimension in a thickness direction of the frame main body.

2. The racket frame according to claim 1, wherein any one of the cross string at an uppermost position and the cross string at a lowermost position and any one of the main string at a leftmost position and the main string at a rightmost position in the frame main body are inserted into the common hole.

3. The racket frame according to claim 1, wherein the inner opening shape is formed such that the opening dimension in the circumferential direction of the frame main body is smaller than an outer opening shape of the common hole on an outer peripheral surface of the frame main body.

4. The racket frame according to claim 1, wherein the main string and the cross string extended in the tensioned state cross each other at a position including an inside of the common hole.

5. The racket frame according to claim 1, wherein a common tubular portion through which the main string and the cross string extended in the tensioned state can be inserted passes through and is attached to the common hole.

6. The racket frame according to claim 5, wherein the common tubular portion includes a first folding wall on which the main string extended in the tensioned state is folded on a base end side, a second folding wall on which the cross string extended in the tensioned state is folded on a base end side, and a pair of side walls connecting the first folding wall and the second folding wall, and wherein, in an inside of the common tubular portion, the main string is capable of being extended in the tensioned state such that the main string is gradually away from the first folding wall from a base end toward a tip end of the first folding wall, and the cross string is capable of being extended in the tensioned state such that the cross string is gradually away from the second folding wall from a base end toward a tip end of the second folding wall.

7. The racket frame according to claim 6, wherein an inner peripheral surface of the tip end of the first folding wall is in contact with the cross string extended in the tensioned state, and wherein an inner peripheral surface of the tip end of the second folding wall is in contact with the main string extended in the tensioned state.

8. A racket comprising: the racket frame according to claim 1; and the plurality of main strings and the plurality of cross strings extended in the tensioned state inside the frame main body.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0010] FIG. 1 is a front view of a racket according to an embodiment.

[0011] FIG. 2 is an enlarged front cross-sectional view of portion A in FIG. 1.

[0012] FIG. 3 is a schematic perspective view of a common tubular portion according to the embodiment.

[0013] FIG. 4 is a B arrow view of FIG. 2 in which a string is omitted.

[0014] FIG. 5 is a C arrow view of FIG. 2 in which the string is omitted.

[0015] FIG. 6 is a view in which a grommet is omitted from FIG. 5.

[0016] FIG. 7 is a cross-sectional view, similar to FIG. 2, of a racket according to a first comparative structure.

[0017] FIG. 8 is a cross-sectional view, similar to FIG. 2, of a racket according to a second comparative structure.

DESCRIPTION OF EMBODIMENTS

[0018] Hereinbelow, an embodiment of the present invention will specifically be described with reference to the drawings. Note that, in the following, an example in which the present invention is applied to a racket for tennis will be described, but the application target is not limited thereto and can be changed. For example, the present invention may be applied to a tennis racket for softball tennis, a racket for squash, a racket for badminton, and the like.

[0019] FIG. 1 is a front view of a racket according to an embodiment of the present invention. As illustrated in FIG. 1, a racket frame 10 constituting a racket 1 includes a frame main body 11 having a substantially elliptical loop shape, a grip 12 which is a portion gripped by a player, and a shaft 13 integrally connecting the frame main body 11 and the grip 12.

[0020] In the following description, as indicated by an arrow in FIG. 1, a longitudinal direction of the racket frame 10 is defined as an up-down direction, a side in the up-down direction on which the frame main body 11 is located is defined as an upper side, and a side on which the grip 12 is located is defined as a lower side. In addition, on a hitting surface 24 of the racket 1 (that is, on a plane along the hitting surface 24), a direction orthogonal to the up-down direction is defined as a right-left direction, and a direction orthogonal to the hitting surface 24 is defined as a thickness direction.

[0021] The shaft 13 includes a throat 15 bifurcating into two sides from the grip 12 toward the frame main body 11 when viewed from a front-back direction. A yoke 17 forming a part (lower side) of the frame main body 11 is formed between the left and right sides of the throat 15. Note that the shaft 13 is not limited thereto, and does not need to be bifurcated.

[0022] The racket 1 includes a string 20 extended in a tensioned state on the frame main body 11 as well as the racket frame 10. The string 20 is extended in the tensioned state inside the frame main body 11 in the up-down direction and the right-left direction. Here, the string 20 is extended in the tensioned state in a meandering manner as described below, thereby forming main strings 21 and cross strings 22 inside the frame main body 11. A plurality of main strings 21 extend in the up-down direction and are extended in a tensioned state to be arranged in the right-left direction. A plurality of cross strings 22 extend in the right-left direction and are extended in a tensioned state to be arranged in the up-down direction. The main strings 21 and cross strings 22 extended in the tensioned state form the hitting surfaces 24 on both surfaces in the thickness direction inside the frame main body 11.

[0023] The frame main body 11 is formed by molding a hollow cylindrical body made of, for example, a fiber-reinforced resin into an elliptical shape. Note that the frame main body 11 may be filled with a foam material instead of being hollow or made of wood or metal.

[0024] An outer peripheral surface 11a of the frame main body 11 is provided with a groove portion 11b in which a central portion in the thickness direction is recessed further than both side portions. The groove portion 11b is provided continuously along a circumferential direction of the frame main body 11. In addition, the frame main body 11 is provided with a plurality of holes 18 along the circumferential direction. The plurality of holes 18 are formed to penetrate from the bottom side of the groove portion 11b to an inner peripheral surface 11c of the frame main body 11, and are formed to have a cylindrical inner peripheral surface shape except for common holes 19 at four locations to be described below.

[0025] The frame main body 11 is provided with four grommets 31 to 34 from the outer peripheral side thereof, and the string 20 is extended in the tensioned state on the frame main body 11 via these grommets 31 to 34. In the present embodiment, the upper grommet 31 is provided from a position approximately in the direction of 10 o'clock to a position in the direction of 2 o'clock in a front view of the frame main body 11. The left and right grommets 32 and 33 are provided from the vicinity of the left and right ends of the upper grommet 31 to positions of reaching the lowermost holes 18 formed in the left and right side surfaces of the frame main body 11. The lower grommet 34 is provided on the yoke 17. Note that the length of each of the grommets 31 to 33 excluding the lower grommet 34 along the circumferential direction of the frame main body 11 may be changed according to various conditions. In addition, the number of the grommets mounted on the frame main body 11 is not limited to four, and may be a plurality of grommets other than four, for example, seven to nine grommets.

[0026] Each of the grommets 31 to 34 may be a molded body formed by injection-molding a thermoplastic resin. Each of the grommets 31 to 34 includes a strip-like portion 36 extending in the circumferential direction of the frame main body 11 and a plurality of tubular portions 37 protruding from a back surface which is one surface of the strip-like portion 36. The tubular portion 37 is formed to have a substantially cylindrical shape except for common tubular portions 39 formed at four locations described below.

[0027] The thickness of the strip-like portion 36 in the left and right grommets 32 and 33 is formed to be smaller than the thickness of the frame main body 11. In the upper grommet 31, the thickness of the strip-like portion 36 is formed to be substantially the same as the thickness of the frame main body 11 to cover the outer peripheral surface 11a on the upper side of the frame main body 11. Note that, in the strip-like portion 36 of the upper grommet 31, the region covering the outer peripheral surface 11a of the frame main body 11 and the region continuous with the tubular portion 37 may be integrated, or may be formed separately and combined.

[0028] The tubular portion 37 has a base end on the side provided with the strip-like portion 36, and a tip end side opposite to the base end passes through the hole 18 from the outside of the frame main body 11. The grommets 31 to 34 are attached to the frame main body 11 by this passing, and in this state, the tip end side of the tubular portion 37 is disposed so as to protrude inward from the inner peripheral surface 11c of the frame main body 11.

[0029] In a case where the string 20 is extended in the tensioned state on the frame main body 11, a procedure of inserting the string 20 into the tubular portion 37 from the inside of the frame main body 11, pulling the string 20 to the outside of the frame main body 11, folding back the string 20 at the base portion of the tubular portion 37, and inserting the string 20 into the next tubular portion 37 is repeatedly performed. Therefore, the main string 21 is extended in the tensioned state in the stringing direction of proceeding in the right-left direction by extending in the up-down direction inside the frame main body 11 and meandering by insertion and folding in the plurality of tubular portions 37. Also, the cross string 22 is extended in a tensioned state in the stringing direction of proceeding in the up-down direction by extending in the right-left direction inside the frame main body 11 and meandering by insertion and folding in the plurality of tubular portions 37.

[0030] Next, the common hole 19 and the common tubular portion 39 according to the present embodiment will be described with reference to FIGS. 2 to 6 in addition to FIG. 1. FIG. 2 is an enlarged front cross-sectional view of portion A in FIG. 1. FIG. 3 is a schematic perspective view of the common tubular portion according to the embodiment. FIG. 4 is a B arrow view of FIG. 2 in which the string is omitted. FIG. 5 is a C arrow view of FIG. 2 in which the string is omitted. FIG. 6 is a view in which the grommet is omitted from FIG. 5.

[0031] Among the plurality of holes 18 formed in the frame main body 11, the common holes 19 having a different shape from a shape of other portions are formed at four locations of an upper right portion, an upper left portion, a lower left portion, and a lower right portion of the frame main body 11 (illustrated by dotted lines in FIG. 1). In addition, among the plurality of tubular portions 37 formed, the tubular portions 37 that pass through and are attached to the four common holes 19 are the common tubular portions 39 (illustrated by dotted lines in FIG. 1).

[0032] The rightmost main string 21 and the uppermost cross string 22 are inserted through the common hole 19 and the common tubular portion 39 in the upper right portion of the frame main body 11. The leftmost main string 21 and the uppermost cross string 22 are inserted through the common hole 19 and the common tubular portion 39 in the upper left portion of the frame main body 11. The leftmost main string 21 and the lowermost cross string 22 are inserted through the common hole 19 and the common tubular portion 39 in the lower left portion of the frame main body 11. The rightmost main string 21 and the lowermost cross string 22 are inserted through the common hole 19 and the common tubular portion 39 in the lower right portion of the frame main body 11.

[0033] The common hole 19 and the common tubular portion 39 in the upper right portion of the frame main body 11 are substantially symmetrical in the right-left direction with the common hole 19 and the common tubular portion 39 in the upper left portion of the frame main body 11. The common holes 19 and the common tubular portions 39 in the upper right portion and the upper left portion of the frame main body 11 are substantially symmetrical in the up-down direction with the common holes 19 and the common tubular portions 39 in the lower right portion and the lower left portion of the frame main body 11. Therefore, in the following description, the common hole 19 and the common tubular portion 39 in the upper right portion of the frame main body 11 surrounded by a two-dot chain line circle indicated by reference sign A in FIG. 1 will be illustrated and described, and detailed description and the like of the common holes 19 and the common tubular portions 39 other than those will be omitted.

[0034] As illustrated in FIG. 2, the common hole 19 in the upper right portion of the frame main body 11 is formed to have an inner peripheral shape along the outer peripheral surface of the common tubular portion 39 passing therethrough. The common tubular portion 39 will be described first. The common tubular portion 39 includes a first folding wall 41 on which the main string 21 is folded on the base end side (the side provided with the strip-like portion 36) and a second folding wall 42 on which the cross string 22 is folded on the base end side. In addition, the common tubular portion 39 includes a pair of side walls 43 (see FIG. 3, one is not illustrated in FIG. 2) connecting the first folding wall 41 and the second folding wall 42 on both sides in the thickness direction. The common tubular portion 39 forms a tip end side opening 45 and a base end side opening 46. The tip end side opening 45 and the base end side opening 46 are formed to have an elongated hole shape or an elliptical shape in which the opening dimension in the circumferential direction of the frame main body 11 is larger than the opening dimension in the thickness direction of the frame main body 11 (see FIGS. 4 and 5). The tip end side opening 45 has a larger opening dimension in the circumferential direction of the frame main body 11 than the base end side opening 46.

[0035] The first folding wall 41 and the second folding wall 42 each extend in a direction inclined with respect to the normal direction of the frame main body 11. The first folding wall 41 and the second folding wall 42 face in directions of approaching each other from the base ends toward the tip ends. The main string 21 inserted into the common tubular portion 39 is gradually away from the first folding wall 41 from the base end toward the tip end, and is in point or local contact with the inner peripheral surface of the first folding wall 41 on the base end side, which is a folded position. The cross string 22 inserted into the common tubular portion 39 is gradually away from the second folding wall 42 from the base end toward the tip end, and is in point or local contact with the inner peripheral surface of the second folding wall 42 on the base end side, which is a folded position (in a similar manner). Note that the directions of the first folding wall 41 and the second folding wall 42 with respect to the normal direction of the frame main body 11 are not limited to the above-described directions, and various changes can be made. For example, at least one of the first folding wall 41 and the second folding wall 42 may extend in a direction parallel to the normal direction of the frame main body 11, or the first folding wall 41 and the second folding wall 42 may face in directions of being away from each other from the base end toward the tip end.

[0036] Inside the common tubular portion 39, the main string 21 and the cross string 22 to be inserted cross each other. Therefore, the main string 21 and the cross string 22 cross each other at a position including the inside of the common hole 19 such that the main string 21 and the cross string 22 fit inside the common hole 19 through which the common tubular portion 39 passes, or straddle the inside and the outside of the common hole 19.

[0037] The common hole 19 forms an inner opening 19a in the inner peripheral surface 11c of the frame main body 11, and forms an outer opening 19b in the groove portion 11b in the outer peripheral surface 11a of the frame main body 11 (see FIG. 6). As described above, the common hole 19 is formed to have the inner peripheral surface shape along the outer peripheral surface of the common tubular portion 39. Therefore, the inner opening 19a and the outer opening 19b are formed to have an elongated hole shape or an elliptical shape in which the opening dimension in the circumferential direction of the frame main body 11 is larger than the opening dimension in the thickness direction of the frame main body 11. The inner opening 19a is formed to have a larger opening dimension in the circumferential direction of the frame main body 11 than the outer opening 19b.

[0038] In the above-described embodiment, the inner opening 19a of the common hole 19 and the tip end side opening 45 of the common tubular portion 39 have shapes of extending in the circumferential direction of the frame main body 11. Due to such shapes, both the main string 21 and the cross string 22 can be inserted into the single common hole 19 (single common tubular portion 39), and the main string 21 can be directed substantially in the up-down direction and the cross string 22 can be directed substantially in the right-left direction in the common hole 19 (common tubular portion 39). Therefore, the main string 21 and the cross string 22 can be brought into a state of not being fixed in the vicinity of the tip end side opening 45 of the common tubular portion 39.

[0039] In the main string 21 and the cross string 22, in a case where a range of flexural deformation of the string by hitting a ball on the hitting surface 24 (see FIG. 1) is referred to as an effective length, an end portion of an effective length L1 of the main string 21 is on the base end inner peripheral side of the first folding wall 41 indicated by reference sign P1 in FIG. 2. An end portion of an effective length L2 of the cross string 22 is on the base end inner peripheral side of the second folding wall 42 indicated by reference sign P2 in FIG. 2. As a result, the end portions P1 and P2 of the effective lengths L1 and L2 can be disposed closer to the outer peripheral surface 11a of the frame main body 11, so that the effective lengths L1 and L2 of the main string 21 and the cross string 22 can be made to be long.

[0040] As described above, the common holes 19 and the common tubular portions 39 are provided at four locations of the upper right portion, the upper left portion, the lower left portion, and the lower right portion of the frame main body 11. Therefore, the effective lengths L1 and L2 of the rightmost and leftmost main strings 21 and the uppermost and lowermost cross strings 22 in the frame main body 11 can be made to be long. The main string 21 and the cross string 22 in which the effective lengths L1 and L2 are made to be long in this manner are easily flexed at the time of hitting a ball, and a so-called sweet area of the hitting surface 24 can be expanded. As a result, the impact transmitted to the player at the time of hitting the ball can be alleviated to improve the hitting feeling, and the control performance and the repulsive-performance of the racket 1 can be improved.

[0041] Furthermore, in the above-described embodiment, the inner opening 19a of the common hole 19 is formed to have a smaller opening dimension in the circumferential direction of the frame main body 11 than the outer opening 19b. As a result, while the effective lengths L1 and L2 are made to be long as described above, the inner opening 19a of the common hole 19 and the tip end side opening 45 of the common tubular portion 39 can be brought into a state of being close to the main string 21 and the cross string 22 without being significantly away from the main string 21 and the cross string 22 in the circumferential direction.

[0042] Further, in the above-described embodiment, the main string 21 and the cross string 22 cross each other at a position including the inside of the common hole 19. Accordingly, it is possible to easily adopt a string pattern in which the stringing range of the main string 21 is enlarged in the right-left direction inside the frame main body 11 and the stringing range of the cross string 22 is enlarged in the up-down direction inside the frame main body 11.

[0043] Here, in order to describe the effects of the common hole 19 and the common tubular portion 39 of the above-described embodiment, first and second comparative structures will be described below with reference to FIGS. 7 and 8. FIG. 7 is a cross-sectional view, similar to FIG. 2, of a racket according to the first comparative structure. FIG. 8 is a cross-sectional view, similar to FIG. 2, of a racket according to the second comparative structure. In description of each comparative structure, similar components to those in the above-described embodiment are labeled with the same reference signs.

[0044] The first comparative structure in FIG. 7 has a configuration in which the main string 21 and the cross string 22 inserted through the common tubular portion 39 in the above-described embodiment are inserted through two cylindrical tubular portions 81 and 82. In the first comparative structure, the two cylindrical tubular portions 81 and 82 are formed similarly to the tubular portion 37 in the above-described embodiment, and the direction of penetrating the frame main body 11 faces in the normal direction of the frame main body 11. In other words, the frame main body 11 has two holes 83 through which the cylindrical tubular portions 81 and 82 pass, and the directions of the central axes of the two holes 83 face in the normal direction of the frame main body 11.

[0045] In the first comparative structure, the main string 21 and the cross string 22 located in the cylindrical tubular portions 81 and 82 are inserted in a direction inclined at about 45 with respect to the up-down direction and the right-left direction. Therefore, the main string 21 and the cross string 22 inserted into the cylindrical tubular portions 81 and 82 have shapes bent at a large angle at the tip ends of the cylindrical tubular portions 81 and 82.

[0046] The main string 21 and the cross string 22 are fixed at the bending positions at the tip ends of the cylindrical tubular portions 81 and 82. In this state, the bending positions are at the end portions P1 and P2 of the effective lengths L1 and L2 of the main string 21 and the cross string 22, and the end portions Pl and P2 are located near the inner peripheral surface 11c of the frame main body 11. Therefore, in the first comparative structure, the effective lengths L1 and L2 are shorter than those in the above-described embodiment. In other words, by providing the common hole 19 and the common tubular portion 39 of the above-described embodiment, it is possible to provide the longer effective lengths L1 and L2 of the main string 21 and the cross string 22 extended in the tensioned state than in the first comparative structure.

[0047] Moreover, in the first comparative structure, the two cylindrical tubular portions 81 and 82 and the two holes 83 are extremely close to each other. This makes it difficult to insert the string 20 through the cylindrical tubular portions 81 and 82 when stringing the string 20.

[0048] In this regard, by providing the common hole 19 and the common tubular portion 39 of the above-described embodiment, it is possible to avoid a state in which the two tubular portions 37 are close to each other, and it is possible to improve workability by eliminating the difficult stringing work as in the first comparative structure. Furthermore, in the above-described embodiment, since the common hole 19 and the common tubular portion 39 have long shapes in the circumferential direction of the frame main body 11, the work of inserting the string 20 into the common tubular portion 39 can be facilitated.

[0049] In addition, the first comparative structure needs to have a layout in which the two cylindrical tubular portions 81 and 82 do not overlap and are away from each other by a predetermined distance. For this reason, the first comparative structure has restrictions in terms of a pattern or an interval of each of the strings 21 and 22, or has restrictions of reducing the number of the strings 21 and 22 to be extended in the tensioned state.

[0050] In this regard, in the above-described embodiment, by inserting both the main string 21 and the cross string 22 into the single common tubular portion 39 (single common hole 19), the degree of freedom in the position and shape of the common hole 19 and the common tubular portion 39 can be increased. As a result, in the above-described embodiment, the degree of freedom of the pattern, the interval, and the number of the strings 21 and 22 to be extended in the tensioned state can be improved further than in the first comparative structure.

[0051] The second comparative structure in FIG. 8 has a configuration in which the main string 21 and the cross string 22 inserted through the common tubular portion 39 in the above-described embodiment are inserted through two cylindrical tubular portions 85 and 86. In the second comparative structure, the two cylindrical tubular portions 85 and 86 are formed similarly to the tubular portion 37 in the above-described embodiment. The cylindrical tubular portion 85 through which the main string 21 is inserted and a hole 87 of the frame main body 11 through which the cylindrical tubular portion 85 passes are parallel to the up-down direction. The cylindrical tubular portion 86 through which the cross string 22 is inserted and a hole 88 of the frame main body 11 through which the cylindrical tubular portion 86 passes are parallel to the right-left direction. Therefore, the effective lengths (not illustrated) of the main string 21 and the cross string 22 in the second comparative structure approximate to the effective lengths L1 and L2 of the above-described embodiment.

[0052] In the second comparative structure, the directions of the central axes of the holes 87 and 88 greatly differ from the normal direction of the frame main body 11 in angle, and are similar to the tangential direction of the frame main body 11. For this reason, the tip end of the drill blade for processing the holes 87 and 88 easily slides at the groove portion 11b and the inner peripheral surface 11c of the frame main body 11, and it becomes difficult to form the holes 87 and 88.

[0053] In this regard, in the above-described embodiment, the common hole 19 and the common tubular portion 39 have long shapes in the circumferential direction of the frame main body 11. Accordingly, even in a case where the direction of the surface on which the common hole 19 is formed is similar to the normal direction of the frame main body 11, the effective lengths L1 and L2 can be made to be long. Therefore, the above-described embodiment can achieve both facilitation of processing of the common hole 19 and obtaining of the long effective lengths L1 and L2.

[0054] Moreover, in the second comparative structure, the two cylindrical tubular portions 85 and 86 and the two holes 87 and 88 are extremely close to each other on the side of the frame main body 11 provided with the inner peripheral surface 11c. Therefore, in a case where the second comparative structure is compared with the above-described embodiment, the above-described embodiment is more advantageous for a similar reason to that described in the comparison between the first comparative structure and the above-described embodiment.

[0055] The present invention is not limited to the above-described embodiment, and various modifications can be made. In the above-described embodiment, the size, shape, direction, and the like are not limited to those illustrated in the accompanying drawings, and can appropriately be changed within the scope of bringing about the effects of the present invention. In addition, the present invention can appropriately be modified and carried out without departing from the scope of the object of the present invention.

[0056] For example, in the above-described embodiment, the configuration in which the grommets 31 to 34 are mounted to the frame main body 11 and the tubular portions 37 (including the common tubular portions 39) are mounted to the plurality of holes 18 (including the common holes 19) has been described, but the present invention is not limited thereto. In the above-described embodiment, the tubular portion 37 may be omitted by performing predetermined processing or inner peripheral surface processing on the hole 18. In this configuration, the inner peripheral surface shape of the common tubular portion 39 in the above-described embodiment is formed as the inner peripheral surface shape of the common hole 19.

[0057] The main string 21 and the cross string 22 passing through the common hole 19 and the common tubular portion 39 are not limited to those in the above-described embodiment. As an example, through the common hole 19 and the common tubular portion 39, the second or subsequent cross string 22 from the uppermost or lowermost cross string 22 may be inserted, or the second or subsequent main string 21 from the rightmost or leftmost main string 21 may be inserted.

[0058] In addition, the locations of the common holes 19 and the common tubular portions 39 are not limited to the above-described four locations of the frame main body 11, and the two upper locations or the two lower locations out of the four locations may be omitted. Furthermore, at each of the above-described four locations, the number of each of the common hole 19 and the common tubular portion 39 is not limited to one, and two or more common holes 19 and two or more common tubular portions 39 may be formed.

[0059] Although the main string 21 and the cross string 22 cross inside the common hole 19 and the common tubular portion 39 in the above-described embodiment, the crossing position may be inside the inner peripheral surface 11c of the frame main body 11 (closer to the center of the hitting surface 24).

[0060] Further, the plurality of holes 18 may be formed at the center positions in the thickness direction, or may be formed in a staggered manner so as to be positioned alternately with respect to the center position. In the configuration in which the plurality of holes 18 are arranged in the staggered manner, a hole through which the main string 21 is inserted and a hole through which the cross string 22 is inserted, which are arranged in a staggered manner similarly to the plurality of other holes 18, are formed instead of the common hole 19 and the common tubular portion 39 in the configuration illustrated in the above-described embodiment. The hole through which the main string 21 is inserted faces parallel to the up-down direction, and the hole through which cross string 22 is inserted faces parallel to the right-left direction. The main string 21 and the cross string 22 inserted into these holes cross each other inside the frame main body 11 when viewed from the thickness direction. Therefore, the effective lengths of the main string 21 and the cross string 22 approximate to the effective lengths L1 and L2 of the above-described embodiment.

[0061] In the above-described embodiment, as the configuration of the present invention, the racket 1 in which the string 20 is extended in the tensioned state inside the frame main body 11 is used as an example, but the present invention is not limited thereto, and the present invention can also be applied to the racket frame 10 in which the string 20 is not extended in the tensioned state.

INDUSTRIAL APPLICABILITY

[0062] The present invention relates to a racket frame and a racket capable of making the effective lengths of a main string and a cross string long.

[0063] The present application is based on Japanese Patent Application No. 2023-002763 filed on Jan. 12, 2023. All the contents of the application are incorporated herein.