JPH0335349Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] This invention relates to a racket frame that enables stringing protection and weight adjustment of the stringing part of a frame such as a tennis racket.

[Technical background of the invention and its problems]

Conventionally, in this type of racket frame,
When adjusting the elasticity of the strings strung on the frame stringing section, it is necessary to vary the overall tension of the strings in the vertical and horizontal directions, or to change the type of strings, or to add elastic material to the string U-turn section on the outer circumferential side of the frame stringing section. In order to further adjust the weight of the frame stringing section, a band-shaped substrate made of synthetic resin is attached to the outer circumferential side of the frame stringing section. Adjustments are being made.

However, with such conventional racket frame adjustment means, not only is it not possible to partially adjust the elasticity of the strings, but also it is not possible to adjust the elasticity of the strings and the weight of the stringed part of the frame at the same time. If this is not possible, and if a string receiving piece is interposed in the gut U-turn on the outer circumferential side of the frame stringing part, the elastic effect of the string will be insufficient, and moreover, the gut U-turn will protrude too much from the outer surface of the frame stringing part. There were inconveniences such as the lack of protection and the tendency to break.

[Purpose of invention]

This idea was made based on the above circumstances, and it is a racket frame that allows for simultaneous adjustment of local elasticity of the strings and partial weight balance adjustment of the stringing part of the frame. The purpose is to provide the following.

[Summary of the idea]

In order to achieve the above-mentioned object, this invention has a stringing part of the frame having a concave groove and a large number of stringing holes in the circumferential direction of the frame, and has stringing holes corresponding to each of the stringing holes on the outer circumferential side of the frame, which also serves as stringing protection. A weight adjustment member can be attached partially, and the weight adjustment member is formed of a band-shaped substrate having a width that straddles the groove, and a width direction between each of the mutually adjacent gut insertion holes of the band-shaped substrate. By alternately arranging plate-like elastic members and cutting grooves, the elasticity of the string and the weight balance can be partially adjusted.

[Example of idea]

This invention will be explained below based on illustrated embodiments.

As shown in Figures 1 to 3, 1 in the figure is a racket frame whose outer shell is made of FRP (fiber-reinforced plastics), for example, and the frame has an approximately oval stringing part 2, a yoke part 3, and a shaft part 4. A groove 5 is formed in the outer circumferential side 2a of the frame stringing part 2 along the circumferential direction of the frame, and guts 7 are folded and stretched vertically and horizontally at the bottom of the groove 5. A large number of gut holes 6 are penetrated and open. On the outer circumferential side surface 2a of the frame stringing section 2, a weight adjusting member 8 which also serves to protect the strings is attached to both the left and right shoulders of the top side excluding the top a in the long axis direction of the frame stringing and the right and left both sides b and b in the short axis direction. These weight adjustment members 8 are partially attached to the portions c, c and the left and right shoulder portions d, d of the yoke side, respectively.
has a configuration in which the stringer 7 is held and fixed from the outside by a U-turn portion 7a of a stringer 7 stretched between mutually adjacent stringer holes 6, 6 in a concave groove 5 formed on the outer peripheral side surface of the frame stringing portion 2.

That is, as shown in detail in FIG. 4, the weight adjustment member 8 described above is composed of a strip-shaped substrate 9 made of thermoplastic synthetic resin such as nylon, and the strip-shaped substrate 9 is attached to the outer circumferential side surface 2a of the frame stringing section 2. A cylindrical gut insertion hole that has a width sufficient to straddle the groove 5 formed in the frame and that can be inserted into the gut hole 6 that extends through the frame stringing section 2 in the longitudinal direction of the back surface thereof. 10 are integrally formed in a continuous manner so as to protrude from the back side of the strip-shaped substrate 9. Each of the cylindrical gut insertion holes 10 opens on the outer surface of the strip-shaped substrate 9, and has adjacent openings 10a, 10a corresponding to the U-turn portion 7a of the gut 7.
A protective groove 11 recessed deeper than the diameter of the gut 7 is formed in between, and the U-turn portion 7a of the gut 7 can be fitted into the protective groove 11.
Then, the tight U-turn portion 7a of the strip-shaped substrate 9
A plate-shaped elastic member 12 made of a plate spring is disposed between adjacent gut insertion holes 10 and 10 corresponding to . It is embedded in the width direction so as to be able to elastically support the gut U-turn portion 7a. In addition, 13 in the figure is the strip-shaped substrate 9.
Openings 10 on the surface side of adjacent gut insertion holes 10, 10 excluding the portion corresponding to the gut U-turn portion 7a of
A cutting groove having a V-shaped cross section cut in the width direction between a and 10a makes it possible to cut and separate the strip-like substrate 9 into appropriate lengths.

By the way, the length of the strip-shaped substrate 9 of the weight adjustment member 8 mentioned above is, for example, about 10 to 12 times the gap between the gut holes, and it is better to make the width as close as possible to the frame width of the frame stringing section 2 in the ball-hitting direction. It is preferable to increase the overall weight, and also when cutting the protective groove 11 on the surface of the strip-shaped substrate 9, the opening of the adjacent gut insertion holes 10, 10 corresponding to the gut U-turn portion 7a is preferable. It is preferable to mold discontinuously between 10a and 10a as a pair.

Therefore, in order to adjust the weight of the racket frame 1 using the above-mentioned weight adjustment member 8, first cut the band-shaped substrate 9 to an appropriate length from the cutting groove 13, and then attach the member itself to the frame. Adjust the weight to each part c, c and d, d of the stringing section 2 to the desired weight. This weight adjustment is carried out by temporarily fixing each cutting member 8 to each part of the frame stringing section 2 with adhesive tape, etc. before stringing the strings, actually swinging the racket frame, and gradually changing the length of each member 8. This is done while varying the Then, when the weight of each member 8 is set, the stringer 7 is strung on the frame stringing section 2 by a normal means with each member 8 attached, and the U-turn section 7a of the stringer 7 is used to tighten the stringer 7. Each of the members 8 can be held and fixed. As a result, if the weight adjustment member 8 is attached to the left and right shoulders c, c on the top side of the frame stringing section 2 and the left and right shoulders d, d on the yoke side, the tight U-turn portions 7a of each part can be recessed. Since it is elastically supported by a leaf spring 12 embedded in the strip-shaped substrate 9 floating above the groove bottom 5a of the groove 5, the elasticity of the vertical and horizontal guts 7 can be partially adjusted at the same time as partially adjusting the weight balance. This makes it possible to expand the sweet spot portion by making the rigidity distribution of the ball hitting surface uniform, and the tight U-turn portion 7a is buried in the protective groove 11 so that it is not exposed on the surface. , there will be no loss of strength.

Note that this invention is not limited to the above-mentioned embodiment, and if the weight adjustment member 8 is attached to the frame stringing section 2 at the top a and the left and right sides b, b, the effect of expanding the gut span can be obtained. This also makes it possible to emphasize the sweet spot. Moreover, the cutting groove 13 of the weight adjustment member 8
Although cut out on the front side of the strip-shaped substrate 9, it is of course possible to cut it on the back side.

[Effect of idea]

As explained above, according to this invention, the weight adjustment member can be partially attached to the outer circumferential side of the frame stringing part, and is held and fixed by tensioning the stringer.
In addition, since the string U-turn part is configured to be elastically supported by an elastic member provided on the weight adjustment member, the user can adjust the weight balance of the racket frame when tensioning the string, reducing individual differences. It is possible to fine-tune the stability of the ball-hitting surface and the moment of inertia in the swing direction, and at the same time, it is possible to partially adjust the elasticity of the gut, so the sweet spot can be enlarged or emphasized according to the user's preference. It has excellent practical effects.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing an embodiment of the racket frame according to this invention, FIG. 2 is an enlarged cross-sectional perspective view of the main part seen from the direction of the line arrow in FIG. 1, and FIG. FIG. 4 is an enlarged sectional view of a main part, and FIG. 4 is a partially enlarged perspective view of the weight adjustment member. DESCRIPTION OF SYMBOLS 1... Racket frame, 2... Frame stringing part, 2a... Outer peripheral side surface, 5... Concave groove, 6... Gut hole, 7... Gut, 7a... U-turn part, 8...
... Weight adjustment member, 9 ... Band-shaped substrate, 10 ... Gut insertion hole, 10a ... Opening, 11 ... Protection groove,
12... Elastic member, 13... Cutting groove, a... Top of frame stringing part, b... Side part of frame stringing part,
c...Shoulder on the top side of the frame stringing section, d...Shoulder on the yoke side of the frame stringing section.

Claims (1)

[Claims for Utility Model Registration] (1) A weight device that also serves as string protector and has string insertion holes corresponding to each of the string holes on the outer circumferential side of the stringing part of the frame, which has grooves and numerous string holes in the circumferential direction of the frame. The adjustment member can be attached partially, and the weight adjustment member is formed of a band-shaped substrate with a width that straddles the groove, and the band-shaped substrate has elasticity in the width direction between adjacent gut insertion holes. A racket frame with alternating parts and cutting grooves. (2) In the racket frame according to claim 1 of the utility model registration, the weight adjusting member is arranged between adjacent strings on the outer surface corresponding to string U-turn portions of the belt-shaped base material on which the strings are stretched. A racket frame characterized by having a protective groove between insertion holes. (3) In the racket frame according to claim 2 of the utility model registration claim, the elastic member is disposed between the gut insertion holes corresponding to the gut U-turn portion, and is arranged so as to straddle the protective groove. A racket frame characterized in that a racket frame is embedded in the back side of a strip-shaped substrate. (4) In the racket frame according to any one of claims 1 to 3 of the claims for utility model registration, the gut insertion hole is formed to protrude in a cylindrical shape from the back side of the band-shaped substrate. A racket frame featuring (5) In the racket frame according to any one of claims 1 to 4 of the claims for utility model registration, the weight adjustment member is attached to both the left and right shoulders on the top side of the outer peripheral surface of the stringing part of the frame, and to the left and right shoulders on the yoke side. A racket frame characterized by being attached to both shoulders. (6) In the racket frame described in any one of claims 1 to 4 of the claims for utility model registration, the weight adjustment member is attached to the top of the outer peripheral side surface of the stringing part of the frame and to the left and right sides. A racket frame featuring