JPH0161068B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a racket for tennis, badminton, etc.

This type of racket has an annular frame integrally formed at the tip of the grip, and strings are stretched over this frame in a mesh pattern. By the way, in conventional rackets, the strings are directly wound around the frame and stretched, and the tension is adjusted by adjusting the tension of the strings. For this reason, when tensioning the gutts on the frame, it is necessary to apply strong tension to the gutts from the beginning, and the frame may be deformed due to uneven tension in the direction of the gutts at the initial stage of tensioning. Since strong tension is applied, there is a problem that the frame is easily deformed. Also, since the string tension changes during the process of stringing the string,
He has the skill to maintain uniform tension over the entire surface of the gutt.

Furthermore, since the gut is directly fixed to the frame, there is a problem in that during use, the impact force from the impact is applied directly to the hand, causing damage to the wrists and elbows.

The object of the present invention is to solve the above problem by making it possible to adjust the degree of tension after the string is tensioned.

That is, in the racket of the present invention, an inflatable tube is attached to the entire outer circumference of the frame, and a gut is stretched over the frame so as to straddle this tube.
It is possible to allow fluid to flow into the tube and to adjust its internal pressure.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the accompanying drawings showing embodiments thereof.

As shown in FIG. 1, the racket of the present invention also has an annular frame 2 integrally formed at the tip of a grip 1, and strings 3 are stretched over this frame 2 in a mesh pattern. An inflatable tube 4 is attached to the entire outer circumference of the frame 2, and a gut 3 is stretched across the tube 4 as shown in FIG. Various materials can be used for the tube 4,
For example, it is made of synthetic resin, metal, glass fiber, etc. If it is made of resin, it may be covered with reinforcing fibers as shown in the figure, or it may be mixed with reinforcing fibers.

The ends of the tubes 4 communicate with each other at the base of the frame 2 and are connected to a cylinder 6 provided at the base of the grip 1 via a guide hole 5 formed in the grip 1. As shown in FIG. 2, a piston 7 is movably fitted into the cylinder 6, and the tube 4, the guide hole 5, and the cylinder 6 are filled with a fluid such as air or oil. A screw 8 is screwed into the opening side of the cylinder 6, and a spring 9 is generated depending on the screwing degree of this screw 8.
As the piston 7 moves forward and backward through the tube 4, liquid enters and exits the tube 4 through the guide hole 5, and its internal pressure is adjusted.

The racket of this invention is constructed as described above,
When tensioning the gut 3, move the piston 7 backward to lower the internal pressure of the tube 4, and then tension the gut 3 so as to straddle the tube 4 to the extent that the frame 2 is not deformed, and complete the tensioning of the gut 3. After, piston 7
is advanced to cause fluid to flow into the tube 4, and the tube 4 is changed from the state shown in FIG. 4 to the state shown in FIG.
is expanded to apply tension to the gut 3, and when the tension reaches a desired value, the movement of the piston 7 is stopped and fixed. When the string 3 is tensioned, a uniform tension is applied to the entire string 3 that comes into pressure contact with the tube 4 according to Pascal's principle, so that a uniform tension is applied to the entire surface of the string 3.

In use, when an impact force is applied to the gut 3 due to a blow, the impact force is alleviated by fluctuations in the fluid within the tube 4, and the impact transmitted to the grip 1 is softened. At this time, if the spring 9 is interposed between the piston 7 and the screw 8 as in the embodiment, the piston 7 will retreat via the spring 9 due to the impact force, and the buffering effect will be further improved. Further, when the fluid is air, the fluid itself has a buffering property.

Next, when not in use, by retracting the piston 7 to lower the internal pressure of the tube 4, the tension in the gut 3 will also decrease, preventing the gut 3 from stretching, and extending the life of the gut 3. .

In the embodiment described above, both ends of the tube 4 are made to communicate with each other, but one end may be sealed and the other end may be made to communicate with the guide hole 5. Also, the piston 7 may be screwed in, depending on the degree of screwing of the piston 7. It is also possible to directly adjust the internal pressure of the tube 4.

Furthermore, depending on the cylinder 6, if it is not possible to apply tension from the beginning of tensioning the gut 3, a branch hole is formed in the guide hole 5, and a constant fluid is supplied from the pressure tank etc. from the branch hole through the check valve. It is also possible to introduce a certain amount.

Further, as shown in FIG. 6, a groove 10 is formed all around the outer surface of the frame 2, a tube 4 is fitted into this groove 10, and a rigid plate 11 made of synthetic resin, steel, etc. is covered on the outer surface of the tube 4. , if the guts 3 are stretched on the frame 2 so as to straddle this rigid plate 11,
Since the gut 3 does not dig into the tube 4, the durability of the tube 4 is increased.

As mentioned above, according to the racket of this invention,
A tube that can be expanded and contracted is attached to the entire outer circumference of the frame, and a gut is stretched across the tube so that fluid can flow into the tube and its internal pressure can be adjusted. The tension can be easily adjusted without requiring any skill, and the tension can be maintained uniformly over the entire surface of the gut without causing deformation of the frame, and the expansion and contraction properties of the tube soften the impact force caused by hits. , won't hurt your wrists or elbows.

Furthermore, by weakening the internal pressure of the tube when not in use, it is possible to prevent the string from elongating, which has the effect of extending the life of the string.

[Brief explanation of drawings]

FIG. 1 is a front view of an embodiment of the racket of the present invention, FIG. 2 is a sectional view of the main part of FIG. 1, and FIG.
4 and 5 are partially cutaway front views for explaining the expansion of the tube, and FIG. 6 is a partially removed perspective view of the main portion of another embodiment. 1...Grip, 2...Frame, 3...Gut, 4...Tube, 6...Cylinder, 7...Piston, 10...Groove, 11...Rigid plate.

Claims (1)

[Claims] 1. An inflatable tube is attached to the entire outer circumference of the frame, and a gut is stretched over the frame so as to straddle this tube, so that fluid can flow into the tube and the internal pressure can be reduced. A racket that is adjustable. 2. The racket according to claim 1, wherein the tube is fitted into a groove formed all around the outer surface of the frame, and a gut is straddled over the outer surface of the tube via a rigid plate. 3. The racket according to claim 1 or 2, wherein the end of the tube is connected to a cylinder with a piston provided in the grip, and the internal pressure of the tube can be adjusted by moving the piston back and forth within the cylinder.