JPS62148677A - Racket - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a racket frame structure.

More specifically, the present invention relates to a frame structure of a racket used for tennis, badminton, squash games, etc., in which guts are stretched over the head frame of the racket in the form of a net, and a ball or the like is hit on the net-like plane, that is, the gut surface.

[Prior Art] A conventional racket related to the present invention generally has a shaft with a handle at the tip connected to a head frame with a string through a throat. The frame structure of the conventional racket is A.
, B will be explained separately.

A-type frame structure: A-type is the most traditional frame structure, in which a large number of gutt holes are drilled through the head frame from the inner circumferential surface to the outer circumferential surface. . Two consecutive guts intersect with each other.
The threads are successively inserted back and forth through the gut holes so as to form groups of parallel lines (usually called vertical guts and horizontal guts), and finally a net-like plane is stretched by applying a predetermined tension.

Frame structure of type B: Type B is an improved version of the frame structure of type A, and the basic frame structure is the same, but as shown in Fig. 9, the outer peripheral surface of the head frame (6) is , concave grooves (
62) to prevent the sword from being exposed on the outer peripheral surface.Furthermore, this is inserted into the groove (B2) of each gut hole (61), And its tip (511) is attached to the head frame (6
) A hollow nipple (5
By fitting the band-shaped plastic member (5) provided with 1), the gut (7) is prevented from protruding from the outer circumferential surface of the head frame (6), and the As shown, the acute-angled contact point formed between the gut (7) and the head frame (6) ((
a) etc.), the elasticity of the nipple causes tightness (
7) to prevent breakage.

[Problems to be Solved by the Invention] First, in the A-type frame structure, when the guts are inserted back and forth through the guttholes and the net-like plane is stretched by applying a predetermined tension, the gutts The contact angle formed by the opening edge of each gut hole is 90 degrees depending on the location.
Since it has an acute angle of less than 100 degrees, vibration and friction occur in the gut when hitting a ball, etc., and stress is concentrated on the opening edge of the gut hole, which is a rigid body, making the gut easy to break.

Second, since a portion of the gut is exposed on the outer circumferential surface of the frame, there is a problem in that the top of the frame is easily rubbed by the coated surface, making it easy for the gut to break.

The B type frame structure was created to solve the problems of the A type frame as described in 1-1 above, and has the effect of alleviating stress concentration at the opening edge of the gut hole to some extent. Although there are still problems such as the following.

First, the gut (7) and the band-shaped plastic member (7), which were originally in contact with each other as shown in FIG.
5) means that as a result of repeated impact, the tip (511) of the nipple (51) may tear as shown in Fig. 12, or the outer opening edge of the gut hole (61) may break as shown in Fig. 13. There is a problem in that each gut (7) bites into the band-shaped plastic member (5) at the bending point of the gut (7) that abuts, and comes into direct contact with the opening edge of the gut hole (61). .

Secondly, a problem common to both types A and 8 is that the large number of gut holes (61) are provided, which prevents improvement in the strength of the head frame (6) (for example, Most of the cracks that occur occur along gut holes).

Thirdly, as a reference point common to both the <A and 8 types, there is a point that points toward the multiple gut holes (6I) or from the outer periphery of the head frame (6) to the inner periphery, and at the same time, the frame (6) Since the normal direction of the curved surface changes in accordance with the curvature of The work becomes complicated and time-consuming.

Furthermore, from the viewpoint of making rackets lighter in weight, which has been advocated in recent years, it has become popular to form rackets from tubular members. However, the frame of the pipe member is divided into an inner wall and an outer wall, and the tensile load of the gut is applied only to the outer wall where the gut comes into contact across the holes. Therefore, the load-bearing capacity of the frame must be strengthened through materials, dimensions, etc.

An object of the present invention is to provide a racket in which a shaft having a handle at the tip is connected to a head frame in which guts are stretched in a net shape through a throat, and to alleviate stress concentration at the gut contact portion 1 in the frame. Another object of the present invention is to provide a racket that reduces friction caused by vibrations at the contact portion caused by impact and extends the useful life of the stringer.

A further object of the present invention is to provide a racket in which the tensile load applied to the strings is applied evenly to both the outer and inner surfaces of the frame.

Furthermore, the present invention facilitates the tensioning work, and
The purpose is to provide a frame structure with improved frame strength.

[Means for Solving the Problems] The racket of the present invention has a head frame in which guts are stretched in a net shape, and a shaft having a handle at its tip.
The racket is connected through a throat, and a number of rollers are provided in the head frame so as to be rotatable about an axis perpendicular to the gut surface, and the gut is engaged with each roller. It is characterized by a structure in which it is stretched in a mesh-like manner.

The head frame has a U-shaped cross section with a groove that opens on the inner circumference side, and a small hole that penetrates from the outer surface of one side wall of the frame to the outer surface of the other side wall through both side walls of the groove. Holes are formed around the entire circumference of the frame to correspond to the spacing between the meshes, and pins are inserted into each small hole, and the roller is rotatably supported around the pin in the groove. By sequentially stretching it across every other roller between two rollers,
Preferably, the material has a firm surface.

The head frame is composed of an upper frame and a lower frame that are arranged on three sides on both upper and lower sides with the gut surface as the boundary, and the upper and lower frames are maintained at a constant interval by placing a plurality of spacers between them. More preferably, the plurality of rollers are provided between the upper and lower frames excluding each spacer.

The roller is preferably drum-shaped, with a diameter at the center portion being slightly smaller than a diameter at the end portions.

[Function] In the racket of the present invention, the gut and the frame are not directly connected, but are connected via rollers.

Therefore, the gut does not have a bent portion with a bending radius smaller than the radius of the roller. Furthermore, even if a portion of the gut surface receives an impact, the entire gut, and thus the entire frame, will receive the impact.

Also, in cases where the frame is vertically arranged on three sides,
The wide hall makes tensioning work particularly easy and can effectively reduce wind resistance. Furthermore, since the narrow roller can be disposed within the hole, for example, by making the diameter of the roller approximately equal to the vertical and horizontal spacing between the guts, it is possible to hold two guts with one roller. Therefore, the number of small holes that need to be drilled in the frame can be reduced by approximately 1". Also, by using the narrow roller, the effect of buffering the impact force and frictional force generated in the gut is even more effective. Improved.

Furthermore, when a drum-shaped roller is used, derailment of the gut can be effectively prevented.

Next, embodiments of the racket of the present invention will be described based on the accompanying drawings, but the present invention is not limited to these embodiments.

[Example] Fig. 1 is a partial perspective view showing an embodiment of the racket of the present invention, Fig. 2 is an exploded perspective view including a cross section taken along line (11)-(II) in Fig. 1, and Fig. 3 is a partial perspective view showing an embodiment of the racket of the present invention. FIG. 1 is a sectional view taken along line (M)-(IIJ) when the frame of the racket shown in FIG. 1 is hollow, FIG. 4 is a sectional view taken along line N-N in FIG. 1, and FIG. Figure 6 is a perspective view of the main parts showing the
)-plane line sectional view, Fig. 7 is an exploded perspective view of the part marked with the symbol ■ in Fig. 5, Fig. 8 is a sectional view taken along the line ■-■ in Fig. 5, and Fig. 9 is a conventionally used racket. FIG. 10 is a partial sectional view of the racket shown in FIG. 9 near the gut hole before use, and FIG. 11 is a partial cross-sectional view of the racket shown in FIG. 9 near the gut hole before use. Fig. 12 is a partial sectional view of the part shown in Fig. 1o near the gut hole after use; Fig. 13 is a folded surface of the part near the gut hole after the other part of the racket shown in Fig. 11 has been used. It is a diagram.

In FIG. 1, (1) is a head frame of a tennis racket. The outer peripheral surface (l) of the head frame +1)
A) has a flat curved surface. Furthermore, on the inner peripheral surface (lb), as shown in the cross-sectional view in FIG.
) has a U-shaped cross section with opposing side walls (Id) and (ld) on both sides. Head frame (1)
may be hollow as shown in FIG. 3, or solid as shown in FIG. Note that the material of the solid portion may be different between the outer portion of the head frame (1) and the solid portion as shown in FIG. 2, or may be formed integrally with the same material. The frame (1) has side walls (ld), (ld) across the groove (1c) corresponding to the spacing of the gut mesh.
A small hole 04) is drilled vertically through the hole. A pin (3) having a length approximately equal to the length from one outer surface to the other outer surface of the side walls (1d) and (ld) can be fitted and fixed into this small hole a4). The pin (3) rotatably supports the roller (2) at the part that crosses the groove (lc) by inserting it into its center hole (2D). It is preferable that it has a drum-like shape.The diameter of the pin should be determined by taking into consideration the position of the small hole 04) for fixing the pin (3), and whether it should be recessed into the groove (LC) or the groove (IC). It is desirable that the edge of the roller (2) coincides with the outer peripheral surface of the roller.The height of the roller (2) is desirably equal to the width of the groove (IC) as much as possible without interfering with the rotation of the roller. The pin (3) is preferably made of a strong material, such as steel, so that its diameter is as small as possible.

In the frame (1), the guts +4) are stretched as follows. That is, the bottom of the groove (1c) (+41
) side, turn each roller (2) from the bottom (141) side of the rollers (2), (2) adjacent to each other,
(2) and bent at each contact portion. Further, both end portions of the gut (4) are brought into contact with the corresponding rollers (2) on the opposite side in parallel and in opposite directions. By repeating this process, the gut (4) is stretched over the frame (1).

By configuring as shown in Figure 1, when the gut (4) is stretched, its bent portion comes into contact with the outer circumferential curved surface of the roller (2), so it is possible to reduce the friction caused by the vibration caused by the impact of the ball. This makes the gut (4) difficult to break and extends its useful life. Furthermore, since the roller (2) is rotatably supported by the pin (3), the friction caused by the displacement of the gut (4) in the direction of the force of the arm is also reduced.
The cut of Guttu (4) is further prevented from rolling. Furthermore, when tensioning in a net shape, even if the tension force is not balanced, the guts (4) can be easily displaced by the rotatable rollers, so the tension is naturally adjusted (beta-plane state). Therefore, the work of stretching the guttet mesh becomes easier, and the unevenness of the mesh due to the biased guttation is reduced, which solves one of the main causes of poor batted ball control.

This one is further added to Gut (4) in frame (1).
) are all locked in the grooves on the inner circumferential surface, so the conventional band-shaped plastic member can be omitted, and it is possible to prevent the gut from breaking due to exposure on the outer circumferential surface. I can do it. Furthermore, the drilling work for the frame (1) only requires drilling a small hole 04) into which the pin (3) extending perpendicularly to the frame surface is inserted, so a simple device can drill the entire frame. It is also possible to make holes all at once around the circumference.

On the other hand, the diameter of the hole to be drilled can be made very small since a very thin, high-strength steel pin can be used, as opposed to inserting a nipple part of a gut or strip-shaped plastic member. At the same time, the tensile force from the gut is evenly distributed and applied to the outer and inner peripheries of the frame via the pins, making it possible to use frames made of relatively inexpensive materials or frames with small cross-sectional dimensions, reducing costs and reducing weight. It also has the effect of

By making the roller (3) shaped like a drum, the gut that comes into contact with it will not be biased toward one end of the roller, but will always be in the center of the roller.

Next, a more preferred embodiment of the present invention will be described with reference to FIGS. 5 to 8.

In Figures 5 to 8, the head frame +1) is divided into an upper frame (old) and a lower frame 02), extending from the upper end of the old throat to the frame top (B), with the mesh plane formed by the gut (4) as the boundary. In addition, a plurality of spacers Oa are integrally interposed between the upper frame 02) and the lower frame 02). In this embodiment, seven spacers Og are arranged between the upper F frames (11) and 02) excluding the throat region.

Since the upper and upper frames Cl11 and (121) are kept at a constant distance from each other by the spacer aa, the inside of the frame (1) except for the throat and the spacer Oa is a hollow hole that communicates with the inside and outside of the frame (1). (It forms 131.

In this embodiment, the hole f131 extends to the upper end of the throat, but it should be understood that the installation range of the hole aa may vary somewhat depending on the manufacturing process.

Inside each hole n, a small hole Q4) is bored in the vertical direction across the J-lower frame Of) and the screen side, and a pin (3) with sufficient strength made of steel etc. is L
The pins (3) are inserted from the upper surface of the frame (old) to the lower surface of the lower frame (02), but at the same time as the frame (1) is inserted, each pin (3) is smaller than the radius of the center part of the circumferential side or the radius of the upper and lower planes. A roller with a drum-like shape (2
), and freely passes through the center hole (21) to rotatably support each roller (2).

The diameter of the roller (2) is determined according to the width of the gutts (the distance between the gutts) on the reticular plane, and
Since the tip of the string (4) passes through the hole f13 which has sufficient space for string tensioning work, it can be easily stretched over the narrow part of each roller (2). The constriction prevents derailment.

The cover groove (161 is the upper frame (II) shown in FIG.
), or each of the upper and lower surfaces of the upper and lower frames 01) and 02), and the frame (1)
It extends all the way around the area. The pin (3) has a small hole (141
After being fitted into the head frame (1), the upper and lower ends of the pin (3) are compressed in the vertical direction, and the pin is rolled to expand in the radial direction, thereby fixing it to the head frame (1).

Next, the cover shown in FIG. 5 is inserted into the cover groove OCj. In addition, the cover groove O
12) The lower surface is preferably a flat surface with almost no irregularities.

In this embodiment, the diameters of the rollers (2) are all the same, but rollers (2) of different diameters may be used depending on the shape of the head frame (1), the method of tensioning the strings, the spacing between the strings, etc. It is also preferable to use Furthermore, it is desirable that the installation interval of the rollers (2) be determined in consideration of practical needs such as the shape of the head frame.

Figure 8 is a sectional view taken along the line ■-■ in Figure 5, in which rollers (2) are placed at appropriate intervals in each hole (03).
) is stopped. The procedure for tensioning the gut (4) will be briefly explained based on FIG.

The tip of the gut (4) is inserted into the hole 03) from the left side near the frame I and the knob (B), and is passed over the roller (2a) located opposite to the roller (2b) located one position below. After that, it is passed again over the roller (2C) on the gut insertion side. Thereafter, the guts (4) are not passed alternately across the rollers (2), but are passed continuously up to the 20th roller (2d) on the right side in the figure, and then the 21st roller (2d) on the right side. 2e) and reaches the roller (2r) at the 21st exit on the left side in the figure. After that, the strings are stretched on each roller (2) at right angles to a group of strings in the horizontal direction that have been strung together, with the contact points of the strings alternating upward and downward. The leading end of the string (4) is placed on the roller (2o) at the 21st opening on the right side in the figure, and then tied to the string already stretched in the vicinity. Appropriate tension is applied to the outermost end of the string (4) to give appropriate tension to the net-like plane, and then it is tied and fixed to the strings in the vicinity, and the tensioning work is completed. However, it should be understood that the above-described tightening procedure is merely an example, and that other methods or procedures may be used.

In the rackets shown in FIGS. 5 to 8, the first to
In addition to having almost the same effect as the embodiment shown in Figure 4,
Furthermore, it produces the following effects.

Since the head frame (1) is arranged on three sides of the upper and lower frames, and the spacer OF3 is interposed, the efficiency of work such as engaging the strings with the rollers is improved, and the string tensioning work can be performed more easily. . Moreover, since a large hole is formed between the upper and lower frames, excluding the integrally disposed spacer portion, a large roller can be used. Therefore, by using rollers with the same diameter as the string spacing, the number of rollers and, in turn, the number of small holes can be reduced, which improves the strength of the frame and facilitates the string tensioning work. An important advantage is that wind resistance is low due to the holes provided for sufficient air circulation. That is, when trying to hit a ball or the like with a racket, the net-like plane of the head frame (1) is moved almost parallel to the direction of the stroke, so the holes between the upper and lower frames of the head frame (1) allow air to pass through well. Less air resistance.

Therefore, deceleration of the stroke speed due to air resistance and blurring in the stroke direction are less likely to occur, which has the advantage of effectively preventing shot errors.

This effect is particularly noticeable in the case of tennis, when performing an over rad serve or backhand volley with a high stroke speed.

[Effects of the Invention] In the racket of the present invention, since the racket is tensioned while changing the lj direction using gutters or rollers, the tension can be easily adjusted and a uniform tension can be applied to the entire racket. Furthermore, the roller part can buffer the impact and frictional force that occurs on the guts, improving the durability of the guts and head frame, and is also effective in preventing injuries such as tennis elbows, which have become a problem in recent years. It is something.

[Brief explanation of drawings]

Fig. 1 is a partial perspective view showing an embodiment of the racket of the present invention, Fig. 2 is an exploded perspective view including a cross section taken along line (II)-[11] in Fig. 1, and Fig. 3 is shown in Fig. 1. (It)-[II) line sectional view when the frame of the racket is hollow, No. 4
The figure is a cross-sectional view taken along the line ■-(to) in FIG. 1, FIG. 5 is a perspective view of main parts showing another embodiment of the racket of the present invention, and FIG. 6 is a cross-sectional view taken from (vI) to (IJI) in FIG. Line sectional view, Figure 7 is the same as Figure 5? ] Figure 8 is an exploded perspective view of the part numbered ■ - ■ in Figure 5.
9 is a perspective view showing the head frame of a conventionally used racket, FIG. 1O is a partial sectional view of the racket shown in FIG. 9 near the gut hole before use, and FIG. Figure 12 is a partial cross-sectional view of the other part of the racket near the Gantt hole before use; Figure 12 is a partial cross-sectional view of the part shown in Figure 10 near the Gantt hole after use;
FIG. 3 is a partial sectional view of the other part of the racket shown in FIG. 11 in the vicinity of the gut hole after use. (Main symbols in the drawing) (1): Head frame (2): Roller (3): Pin (4): Gut (LC): Groove (13), Hole A4): Small ~ 8 years old 9 years old 7 years old

Claims (1)

[Scope of Claims] 1. A racket in which a head frame having a net-like string stretched thereon and a shaft having a handle at its tip are connected via a throat, the head frame having a large number of rollers. A racket that is rotatably provided around an axis perpendicular to a string surface, and the string is stretched in a mesh shape by being engaged with each roller. 2. The head frame has a U-shaped cross section with a groove that opens toward the inner circumference, and a small hole that penetrates from the outer surface of one side wall of the frame to the outer surface of the other side wall through both side walls of the groove is formed in a mesh of the gut. A pin is inserted into each small hole, and the roller is rotatably supported around the pin in the groove, and the gut is sequentially every other 2
The racket according to claim 1, wherein the string surface is formed by stretching the racket between two rollers. 3. The head frame is composed of an upper frame and a lower frame that are divided into upper and lower sides with a gut surface as a boundary,
Further, the upper and lower frames are maintained at a constant interval by arranging a plurality of spacers, and the plurality of rollers are provided between the upper and lower frames excluding each spacer, according to claim 1. racket. 4. The racket according to claim 1, wherein the roller is drum-shaped, with a diameter at the center being slightly smaller than a diameter at the ends.