JPH11128407A - Flexibility measuring of golf club shaft - Google Patents

Abstract

PROBLEM TO BE SOLVED: To allow easy and accurate measurement of the flexibility of any portion and any direction of the shaft of a golf club during swing to coping with any speed of the head. SOLUTION: In a flexibility measuring method for the shaft 1A of a golf club 1 during swing, plural markings are applied to the shaft 1A at preset spaces in the longitudinal direction, the swing of the club 1 with the marked shaft 1A is photographed with a camera 2 set in the direction of developing the flexibility, portions of the markings of the shaft 1A on the image are digitized to find the coordinates of the marking positions and find the flexibility of the shaft 1A from the coordinates.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a method of swinging a golf club and measuring a deflection of a shaft generated during the swing.

[0002]

2. Description of the Related Art To measure the deflection of a golf club shaft, the grip end position is fixed so that the shaft is horizontal with a position distant from the grip end of the shaft by a predetermined distance as a fulcrum. A weight of a predetermined weight is hung on an inner part separated by a predetermined distance, a static measuring method for measuring the amount of vertical deformation of the shaft tip position caused by this, and a strain gauge is attached to an appropriate position of the shaft, and a gauge attaching position generated at the time of swinging There is known a dynamic measurement method for measuring the strain of a laser.

[0003]

The static method of suspending a weight at a predetermined position of the tip of a shaft set horizontally is measured when a golf club whose desired result is actually swung is swung. It has little bearing on shaft deflection for a particular head speed.

A dynamic measuring method using a strain gauge is as follows.
The lead wire connected to the gauge extends from the shaft, which is very troublesome when measuring at the time of swing.

SUMMARY OF THE INVENTION Accordingly, the present invention provides a golf club shaft flexure that can easily and accurately measure flexure in any direction of any portion of the shaft during a golf club swing, corresponding to any head speed. It is intended to provide a measuring method.

[0006]

In order to achieve the above object, the present invention relates to a method of measuring the deflection of a shaft caused by swinging a golf club and swinging the golf club at a predetermined interval in a longitudinal direction of the shaft. When a club equipped with this marked shaft is swinging with a plurality of marks, the image is taken by a camera set in a direction in which the deflection appears, and the shaft mark portion on the image is digitized to coordinate the mark position. Is obtained, and the deflection of the shaft is obtained from the coordinates.

[0007]

Preferred embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 shows the relationship between the club 1 and the camera 2 when the player P swings the golf club 1. That is, the arrangement of the camera 2 for measuring the deflection of the shaft 1A that occurs in the swing direction when swinging the golf club 1 is shown, and the shaft 1A is swung during the swing so that the entire shaft 1A is evenly in the field of view of the camera 2.
The camera 2 is tilted so that the direction of the lens is substantially orthogonal to the virtual plane drawn by the camera, and the tee position where the ball is set so that the ball impact position is the center of the screen with respect to the swing direction of the club 1. Is set. In this embodiment, the type of the club 1 is a driver, and the shaft 1A is black and a symmetrical white tape is wrapped around the shaft 1A at equal intervals in the longitudinal direction of the shaft 1A.
Marks were wound around. The camera 2, or more precisely, the imaging unit, includes a lens, an image intensifier, a relay lens, and a high-definition camera so that high-speed shooting can be performed even under weak light.

In imaging or photographing, take-back is performed from the position of the address shown in FIG. 2 and the ball B is hit by swinging. The deflection of the shaft 1A is centered on the position where the ball B is hit. If you want to measure the
Although illustration is omitted, for example, when a sensor using a photoelectric tube using light as a medium, the golf club 1 reaches a predetermined position, a detection signal is sent to an image intensifier gate unit (not shown) described later. send. In FIG. 2, 1B indicates a grip and 1C indicates a head.

The photographed image is sent to a high-vision memory (not shown), and the image shown in FIG. 3 is displayed on a high-vision monitor. The images on the monitor are substantially only bright colors (white tapes a, b, c... F) indicating the positions attached to the shaft 1A, and the positions V, W, X, Y, and Z on the swing path are displayed on one screen. It is projected on. On the other hand, image information is sent from the HDTV memory to an image processing board (not shown), and the position of the mark on the shaft 1A is digitized and coordinated as shown in FIG.

Next, as shown in FIG. 5, the position ef (straight line) near the grip 1B where the shaft 1A does not substantially bend is extended, and the position on the straight line corresponding to the positions a, b, c. A distance L from the position coordinates is calculated.

FIG. 6 shows time t on the horizontal axis and the amount of deflection L on the vertical axis in relation to the shutter interval.
A plot of the amount of deflection L of the shaft 1A at the mark position a in W, X, Y, and Z. Note that the position X substantially corresponds to the impact position. Needless to say, graphs can be similarly formed at positions other than the mark position a.

By setting the position of the camera to the rear opposite to the direction of the hit ball, the vertical deflection of the shaft 1A near the impact position can be measured.

[0014]

As described above, according to the present invention, in a method of swinging a golf club and measuring the deflection of the shaft caused during the swing, a plurality of marks are formed at predetermined intervals in the longitudinal direction of the shaft. At the same time, when swinging a club equipped with this marked shaft, take a picture with a camera set in the direction in which the flexure appears, digitize the mark of the shaft on the image to obtain the coordinates of the mark position, Since the deflection of the shaft is obtained from the coordinates, the partial deflection in the longitudinal direction of the shaft can be easily and accurately measured in accordance with the head speed, which is a powerful weapon in developing a golf club.

[Brief description of the drawings]

FIG. 1 is a view showing the positional relationship between a golf club and a camera as viewed from behind a flying ball.

FIG. 2 is a front view of the player at the time of addressing.

FIG. 3 is an image view projected on a monitor.

FIG. 4 is a diagram in which mark positions on a shaft are digitized and converted into coordinates.

FIG. 5 is an explanatory diagram for calculating bending of a shaft.

FIG. 6 is a graph showing the relationship between the passage of time and the amount of bending during the swing of the shaft.

[Explanation of symbols]

 1 golf club 1A shaft 1B grip 1C head 2 camera

Claims (1)

[Claims] 1. A method of measuring the deflection of a shaft caused by swinging a golf club and swinging the golf club, wherein a plurality of marks are provided at predetermined intervals in a longitudinal direction of the shaft, and the club having the marked shaft is provided. When swinging, take a picture with the camera set in the direction in which the deflection appears, digitize the mark of the shaft on the image, find the coordinates of the mark position, and find the deflection of the shaft from the coordinates. Of measuring the deflection of a golf club shaft.