JPH09215781A - Sports racket - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sports racket with which the control of a ball has been improved. SOLUTION: Concerning the sports racket having a grip part and a frame provided with a string network having longitudinal string segments 62 and 63 and lateral string segments 61 and 64, an improved product has the odd number of longitudinal strings and a longitudinal center string 41 matched with a central axis 8 of the racket and since the arrangement of string segments, fixture to the frame, the arrangement of accessories and the attachment of the frame become a mirror image to the axis of the frame, the balance, power and handling of the racket are improved in symmetrical and well- balanced configuration.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to, for example, tennis,
The present invention relates to an innovative gut tension and frame structure for gut tension of sports rackets such as racket balls and badminton squash.

[0002]

BACKGROUND OF THE INVENTION A conventional string network has an even number of vertical string segment systems that are substantially parallel to the axis of the frame and a transverse string system that is substantially perpendicular to the vertical string system. In the case of a tennis racket, the structure of the frame is symmetrical about the axis of the racket, usually having 16 to 20 vertical string segments, which are evenly distributed on either side of the longitudinal axis without strings. A conventional racket is shown in FIG. 1, where frame 10 is top portion 1, side frame 2, throat 3 opposite the top,
It has a shank 4 and a handle (grip) 5. The string network 6 has a longitudinal string system 7 and a transverse string system 9 substantially parallel to the axis 8 of the frame. In most racket designs, the strings are secured around the frame by string holes drilled in the center plane of the frame shown by plane M in FIGS. 4 and 5. Thus, the string exhibits a reaction force component normal to the central plane M of the string network, such that the string returns the ball only when it is recessed deep enough to create a sufficient tilt angle with respect to the central plane. For strings 12 near the border of the frame, the vertical deflection is always small and the string network in the border zone is weakly tensioned and ineffective.

The features of the present invention are shown in the tennis racket of FIG. In FIG. 2 there is a vertical string segment 21 on the center line 8 of the frame, the remaining vertical string segments being distributed as mirror images on both sides of the central vertical string 21 and connected to each other. The transverse string segments woven above and below the corresponding longitudinal string segments are also arranged as mirror images of this centerline. Therefore, the string pattern and stress on the frame are symmetrical and balanced with respect to the central axis of the racket. The present invention, which deviates from the typical gut-tensioning pattern of a sports racquet, improves the performance of the racquet, but proves to be difficult to gut properly. The problem with gut-tensioning has been the long-standing consensus that there are no rackets with vertical strings in the centerline of the frame, so almost all existing commercial gutt-tensioning machines gutt rackets with strings in the centerline of the frame. It is mechanically difficult to stretch. This fact shows that the present invention is not obvious and was not expected.

[0004]

According to a first aspect of the present invention, a sports racket has a handle and a frame, and the frame has a vertical axis which is a central axis of the racket. , The frame has a top portion, two sides and a throat, and more generally defines a region hit by the ball, has a central plane that evenly divides the thickness of the frame, and a plane of symmetry perpendicular to the central plane. A central axis and having an odd number of vertical string segments extending substantially parallel to the longitudinal axis of the frame and extending from the top portion of the frame toward a handle, the vertical string segments being respectively a top portion and an opposite Has two ends fixed by a side frame, and the odd number of string segments are at least substantially aligned with the central axis of the racket. The vertical string segment has a ring segment and a plurality of horizontal string segments at an angle with the vertical string segment, the horizontal string segment having two ends separately fixed on both sides of the frame. And transverse string segments are woven in a substantially planar string network in the central plane, the plurality of string segments form a plurality of string loops to secure the plurality of string segments to a frame, and the plurality of string segments and the The string loop is arranged as a mirror image of the plane of symmetry.

According to a second aspect of the present invention, in the first aspect, most of the plurality of vertical string segments are joined together by a fork device so that the mirror image gut pattern is possible. Contains at least two strings.

According to a third aspect of the present invention, in the aspect of the second aspect, the fork device is arranged substantially along a central axis of the frame.

According to a fourth aspect of the present invention, in accordance with the second aspect, the at least two strings include string segments and loops for the cross string system.

According to a fifth aspect of the present invention, in the fourth aspect, three strings are used to provide the string segments and loops of the racket.

According to a sixth aspect of the present invention, in the first aspect, the ends of the plurality of string segments measured from the center plane to the ends are different from each other in a direction perpendicular to the center plane, and The value of is from zero to the maximum value.

According to a seventh aspect of the present invention, in the sixth aspect, the ends of adjacent segments of the plurality of transverse string segments are arranged in opposite directions from the center plane of the frame.

According to an eighth aspect of the present invention, in the seventh aspect, the ends of adjacent segments of the plurality of transverse string segments are arranged along a substantially straight line parallel to the center plane of the frame.

According to a ninth aspect of the present invention, in the sixth aspect, the plurality of end portions of the plurality of string segments are supported by being wound around the frame instead of passing through an opening formed inside the frame. To be done.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention is applied to a general sports racket having a string network. A tennis racket is shown as an example to illustrate the invention.

FIG. 1 shows a prior art racket frame 10 having a string network. FIG. 2 illustrates a feature of the invention in which a frame 20 has vertical string segments 21 that coincide with the vertical centerline 8 of the frame and are symmetrically distributed as mirror images on either side of the central string. It has an odd number of vertical string segments. A segment is defined as an end-to-end string within the frame boundaries. The ends of the segments are connected via loops 24 and 25 to form a single string. The lateral string segments are supported by the vertical string segments. The merits of the mirror image pattern are clear from FIGS. 1 and 2 and in these figures the ball 17
Hits the center line of the racket. In the conventional string system of Figure 1, the ball contacts at most four longitudinal strings. Inner pair 15 and 14 and outer pair 13 and 1
6 is woven asymmetrically with respect to the center line. The resultant force is tilted with respect to the plane of the frame. Therefore, the ball does not bounce along the direction perpendicular to the frame even if it hits the center line of the frame. Players have long tolerated this inaccuracy as a tool. Good players have learned to compensate for this error.

However, when the same ball 17 hits the centerline string 21 of the frame of FIG. 2, the ball contacts the three vertical string segments 21, 22 and 23, and in the case of a strong hit, two more balls from the outside. The string can be touched. The resultant force, including the force from the transverse string segments, is approximately perpendicular to the center plane of the frame due to the mirror image string construction of the string. This improvement is important for experienced players. They can be confident that if the ball hits the racket centerline it will be returned along a line perpendicular to the racket frame.

Another advantage of the present invention is shown in FIG. 3 and the view along section plane 4-4 is shown in FIG. In a type of string pattern in which multiple strings are fixed to the frame at multiple points that are separated from the center plane M of the frame by a certain distance, the weave pattern is exactly symmetrical and the vertical string segment portion near the frame boundary is centered. It is inclined to the axis. This not only improves the stress distribution and reduces distortion of the frame along the two sides, but it also makes the racket easier to handle because the structure and string network are balanced against the centerline of the frame. The ends of the segments are frame-opening (elevated openi
ng) is wrapped around the frame instead of going through for fixing). Details regarding the distortion of this frame are described in FIGS.

In FIG. 3, the end point 4 of the central vertical string 21
1 is fixed to the upper half L of the frame and the ends 42 of adjacent string segments are on the opposite half H of the frame. Fixed points in the same region, such as 41 and 43, are located along line 44, which line 44 is approximately with respect to line 44 and plane M formed by the endpoints of the opposite region as shown in FIG. It is symmetrical. Similarly, the end points of the lateral string segments are also spaced apart from the center plane of the frame. The endpoint trajectory line 44 may be a curve, a straight line or a compound line including line and arc elements.

FIG. 5 is a sectional view taken along line 6-6 of FIG. This figure shows a transverse string segment 61 fixed to side 2 of the frame. This horizontal string is 2 in the lower half L
All of the odd numbered vertical strings, such as 1, 63, etc., are woven up and down, and in the upper half H, the even numbered segments, such as 62, are woven up and down.
The transverse string adjacent to 61 is 64, which is tilted at an angle to the M plane opposite 61. This tilt stretches the string, increasing the string tension when the ball strikes. Control is improved when the string segments are wound symmetrically on both sides of the frame. FIG. 5 shows a so-called mirror image structure. The string pattern remains symmetrical about the centerline 8 when the player rotates the racket 180 °.
Since the conventional racket had asymmetrical inclination at both ends,
If the left endpoint is above, the right endpoint is below. This is not a desirable feature.

FIG. 6 shows the string pattern of the frame of FIG. 2, in which one string 81 spans the entire vertical string system. The segment within the frame boundary is a mirror image about axis 8 but loop 6
The overall string pattern including 6, 67 is asymmetric about axis 8. In fact, if a single string is used to complete the longitudinal string system from end a to end b, the frame will disperse couples 82 and 83.
Strongly twisted by. FIG. 7 shows the same frame as in FIG. 2 stretched by two strings of a first piece 84 and a second piece 85. Since these strings are joined by a fork 86 near the axis of the frame, there will be two identical strings that are split at 86 and extend outwards, forming a two symmetrical longitudinal string system. This is the mirror image pattern preferred by the present invention. The second end d of 84 is fixed to the frame. Alternatively, the second end can be tied to an adjacent string. Of course, the fork 86 may be located in the head portion instead of the throat. Alternatively, the string may be specially formed for the present invention and the two pieces may be joined at 86 to form a fork rather than being joined by tying as shown. Other ways of joining the two pieces together are possible. All of these practical configurations are referred to herein as fork devices. In the configuration of FIG. 7, the two end forces 87 and 88 are parallel forces, pulling in the same axial direction. This is a significant improvement over the single string configuration of FIG. Note that the fork device causes loops such as 68, 69 to be mirror images of axis 8.

The mirror image gut tension pattern improves vibration and controllability. Centered string and odd number of symmetrical mirror image vertical string pattern,
And without the two fork devices in a vertical string configuration, these improvements would not be possible.

Therefore, it will be apparent to those skilled in the art that modifications may be made to the invention without departing from the principles and scope of the invention.

[Brief description of drawings]

FIG. 1 is a prior art tennis racket frame.

FIG. 2 shows an embodiment of the present invention.

FIG. 3 shows another embodiment of the present invention.

FIG. 4 is a sectional view of a portion 4-4 in FIG.

5 is a cross-sectional view taken along line 6-6 of FIG.

FIG. 6 shows a gut tension pattern with a single vertical string.

FIG. 7 shows a gut tension pattern with two vertical strings.

[Explanation of symbols]

20 frame 1 top part 2 side frame 3 throat 4 shank 5 handle 6 string network 7 longitudinal string system 8 centerline 9 lateral string system 21, 22, 23, 41, 42, 43, 61, 64
Horizontal string segment 62, 63 Vertical string segment

 ──────────────────────────────────────────────────の Continuation of front page (71) Applicant 596166106 1839 Jackson Road Pen field New York 14526 United States of America

Claims (9)

[Claims] 1. A sports racket, the sports racket having a handle and a frame, the frame having a vertical axis which is a central axis of the racket, the frame having a top portion, two sides and a throat. Has a central plane that generally defines the area that the ball hits and that evenly divides the thickness of the frame, the plane of symmetry perpendicular to said central plane including the central axis and being substantially parallel to said longitudinal axis of the frame And having an odd number of vertical string segments extending from the top portion of the frame towards the handle, the vertical string segments each having a top portion and two ends secured by the opposite frame. , The odd-numbered string segments have at least a central string segment substantially coincident with the central axis of the racket, and the vertical string segment A plurality of horizontal string segments at an angle with each other, each of the horizontal string segments having two ends fixed separately on both sides of the frame, the vertical string segment and the horizontal string segment having the central plane. In a substantially planar string network, wherein the plurality of string segments form a plurality of string loops to secure the plurality of string segments to a frame, the plurality of string segments and the string loops with respect to the plane of symmetry. A sports racket placed as a mirror image. 2. The sport of claim 1, wherein a majority of the plurality of vertical string segments comprises at least two strings joined together by a fork device to allow the mirror image gut tension pattern. racket. 3. The sports racket according to claim 2, wherein the fork device is arranged substantially along a central axis of the frame. 4. The sports racket of claim 2, wherein the at least two strings include string segments and loops for the cross string system. 5. The sports racket of claim 4, wherein three strings are used to provide the string segments and loops of the racket. 6. The end of each of the plurality of string segments measured from the center plane to the end is different from each other in a direction perpendicular to the center plane, and these values are from zero to a maximum value. Sports racket. 7. The sports racket of claim 6, wherein the ends of adjacent segments of the plurality of transverse string segments are oriented in opposite directions from the center plane of the frame. 8. The sports racket of claim 7, wherein the ends of adjacent segments of the plurality of transverse string segments are located along a substantially straight line parallel to the center plane of the frame. 9. The sports racket of claim 6, wherein the plurality of ends of the plurality of string segments are wrapped around and supported by a frame instead of passing through an opening formed inside the frame.