JP3262873B2 - Method and apparatus for measuring drag and lift of pseudo golf ball - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pseudo golf ball (measurement object) having dimples of a predetermined shape formed on the outer peripheral surface of a cylindrical body or the like. characteristics, measuring the drag-lift pseudo golf ball made it possible to particularly measuring the drag coefficient and lift coefficient
It is related to a fixing device .

[0002]

2. Description of the Related Art Conventionally, when measuring the aerodynamic characteristics of a golf ball, in particular, the drag coefficient and the lift coefficient, after the golf ball is commercialized, the drag coefficient and the lift coefficient are measured using the golf ball and measured in a wind tunnel device or the like. Was measured using The aerodynamic characteristics of the golf ball, particularly the drag coefficient and the lift coefficient, are factors that have a significant effect on the flight distance of the golf ball, and the ratio between the drag coefficient and the lift coefficient, that is, the lift-drag ratio is large, By determining whether the distance is small, the flight distance of the golf ball can be determined.

[0003]

However, conventionally, when designing a new golf ball, there is no apparatus or method for measuring the drag coefficient and the lift coefficient until the golf ball is commercialized to some extent. Therefore, a great deal of cost, labor, and a long period of time are required before designing a desired golf ball.

The present invention has been devised in view of such a conventional problem. The shape of a dimple formed on the surface of a golf ball is formed on the surface of an object to be measured such as a cylinder , and the shape of the dimple is determined. An object of the present invention is to provide a pseudo golf ball drag / lift measurement device that can easily measure a drag coefficient and a lift coefficient of a target golf ball by simulation by using a pseudo golf ball as a measurement body. Things.

[0005]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention forms a concave portion or a groove portion on the outer peripheral surface having a shape similar to the shape of a dimple formed on the surface of a golf ball.
Drag the cylindrical object to be measured via the shaft.
A lift-measuring device, and a wind-tunnel device for installing the object to be measured, wherein the drag-lift measuring device is a strain-type center shaft 3 that connects and supports a rotatable shaft via a rotation drive control device.
A component force detector, a signal processor connected to the strain type central axis 3 component force detector via a DC type strain amplifier, and calculating a signal processed by the signal processor to obtain a drag coefficient and a lift coefficient. And a control device for determining

[0006]

The present invention is constructed as described above, and has a concave or groove formed on the outer peripheral surface of the shaft of the drag / lift measuring device, the concave or groove having the same shape as the dimple formed on the surface of the golf ball at the tip of the shaft. A column-shaped object to be measured is attached, and the object to be measured is arranged in a measuring section of the wind tunnel device, and while the object to be measured is rotated at a predetermined number of revolutions in the measuring portion, and a predetermined flow rate from one side of the wind tunnel device Rectification to the measuring section,
At this time, the distortion generated in the shaft is transmitted to the sensing part of the strain-type central three-component force detector of the drag / lift measurement device and converted into an electric signal, and the converted electric signal is processed by a signal processor. By calculating the output from the measuring instrument with a computer and determining the drag coefficient and the lift coefficient of the measured object, the drag coefficient and the lift coefficient can be easily measured with the measured object having the target dimple. Things.

[0007]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 shows the drag force of the present invention.
FIG. 1 shows a schematic configuration diagram of a lift measuring device 1. The drag / lift measuring device 1 has a cylindrical object 2 mainly formed with a groove having a shape similar to the shape of a dimple formed on the surface of a golf ball on an outer peripheral surface. An aluminum shaft 3 to which the aluminum shaft 3 is attached, a strain type central shaft 3 component force detector 4 in which the aluminum shaft 3 is connected via an acrylic resin plate 3a, and a DC type strain amplifier 5 And a signal processor 6 connected via the

A base end of the aluminum shaft 3 is connected to a power controller 8 via a drive motor 7, and a digital tachometer 9 is connected to a side surface of the aluminum shaft 3. As shown in FIG. 2, for example, the cylindrical object 2 is formed in a cylindrical shape having a diameter substantially equal to the diameter of a large golf ball (42.67 mm) and a length of 100 mm. On the outer peripheral surface, a long groove 10 is formed at predetermined intervals in the circumferential direction and has the same shape as the cross-sectional shape of the dimple, and a long groove 10 is formed in the longitudinal direction to simulate an actual golf ball.

When measuring the drag coefficient and the lift coefficient of the measured object 2 by attaching the cylindrical measured object 2 to the aluminum shaft 3 as described above, the wind tunnel apparatus 1 shown in FIG.
1 is performed. This wind tunnel device 11 is a suction type wind tunnel manufactured for the purpose of performing aerodynamic measurement and flow visualization, and can measure an average flow velocity of 0 to 60 m / sec. The wind tunnel device 11 mainly includes the rectifier 1
2, a contraction section 13 having a contraction length ratio of 0.9 and a contraction area ratio of 9: 1, a measuring section 14 having a square cross section, and a measuring box 15 through which a person can enter and exit, and rectification. The section 12 is composed of a rectifying wire mesh 16a and a rectifying grid 16b, the measuring section 14 is made of a transparent acrylic resin plate, and is configured so that the measurement state can be visualized from the outside. An opening / closing door (not shown) is provided to facilitate installation of the device under test 2.

Next, a method of using the apparatus of the present invention will be described. First, in the measurement by the drag / lift measuring apparatus 1, the object 2 is fixed to the tip of an aluminum shaft 3, and the object 2 and the aluminum The shaft 3 is installed on the measuring unit 14 of the wind tunnel device 11. In this state, the device under test 2 is moved in the measuring section 14 by the drive motor 7 and the power controller 8.
At a predetermined rotation speed, and at the same time, wind of a predetermined flow velocity is sent from a blower (not shown) provided on one side of the wind tunnel device 11, and the wind is rectified by the rectifier 12 to be measured. The body 2 is sent to the measuring unit 14 in which the body 2 is installed.

When the object 2 is rotated at a constant speed in such a state, a distortion occurs in the aluminum shaft 3, and this distortion is transmitted to the sensing part of the strain type central shaft 3 component force detector 4. Converted to electrical signals. The converted electric signal is signal-processed by a signal processor 6 via a DC-type distortion amplifier 5, and the processed signal is used to calculate an output from a measuring instrument by a computer to obtain a drag coefficient and a lift coefficient. Things.

In practice, first, before the measurement, the Reynolds number and the rotation speed of the aluminum shaft 3 are changed,
Measure each component force. At this time, the flow velocity is 20 to 53 m / sec.
c, The rotation speed can be up to 100,000 rpm. In the same manner as the aluminum shaft 3, the cylindrical object 2 was measured for the Reynolds number, the number of revolutions, and each component force when the shape of the cylindrical surface was changed, and the object 2 as a pseudo golf ball was measured. A value obtained by subtracting the measured value of the aluminum shaft 3 from the measured value is subjected to an averaging operation by the signal processor 6 to remove a disturbance component, and thereafter, the measurement is performed by the above-described method.

According to the present invention, as described above, a cylindrical recess or groove formed on the outer peripheral surface of the aluminum shaft 3 of the drag / lift measurement device 1 is formed at the tip of the aluminum shaft 3 in the same shape as the dimple formed on the surface of the golf ball. Attach the object to be measured 2,
Since the measured object 2 is arranged in the measuring section 14 of the wind tunnel device 11 and the drag coefficient and the lift coefficient of the measured object 2 are obtained by the drag / lift measuring device 1, the actual golf ball is manufactured as a conventional product. Even if the golf ball is not formed, the drag and lift can be measured in substantially the same state as the golf ball, whereby the drag coefficient and lift coefficient similar to those of the golf ball having the desired dimple can be easily obtained. It can be measured.

[0014]

According to the present invention, there is provided a reaction force for mounting a cylindrical object to be measured having a concave or groove having the same shape as the dimple formed on the surface of the golf ball as described above on the outer peripheral surface thereof through a shaft. A lift force measuring device and a wind tunnel device for installing the object to be measured, wherein the drag force / lift force measuring device is a strain-type central shaft three-component force detector that supports and supports a rotatable shaft via a rotation drive control device. A signal processor connected to the strain-type central axis three-component detector via a DC-type strain amplifier, and a control device that calculates a signal processed by the signal processor to obtain a drag coefficient and a lift coefficient And the following excellent
It is effective. (I). Golf ball when fruit not been commercialized, it is possible to measure the drag-lift substantially in the same state as a golf ball. (B). Golf balls actually is not commercialized, inexpensive, and a similar drag coefficient and a golf ball having dimples of interest and the coefficient of lift can be conveniently measured in a short time. (C). Because the structure of the measured object is simple,
It can be easily manufactured.

[Brief description of the drawings]

FIG. 1 is a graph showing the resistance of a pseudo golf ball embodying the present invention;
It is a schematic structure figure of a lift measuring device.

FIG. 2 is a partial perspective view of an object to be measured simulated for a golf ball.

FIG. 3 Implements a drag / lift measurement device for a pseudo golf ball.
It is a schematic front view of the wind tunnel apparatus used at the time of performing.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 drag / lift measurement device 2 object to be measured 3 shaft (aluminum shaft) 4 strain type center shaft 3
Component force detector 5 DC type distortion amplifier 6 Signal processor 7 Drive motor 8 Power controller 9 Digital tachometer 10 Long groove 11 Wind tunnel device 12 Rectification unit 14 Measurement unit

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-1-175872 (JP, A) JP-A-61-175541 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G01M 9/00-9/06 G01L 5/16 A63B 37/00

Claims (1)

(57) [Claims] 1. A recess or groove having a shape similar to the shape of a dimple formed on the surface of a golf ball is formed on the outer peripheral surface.
And a wind tunnel device for installing the measured object, wherein the drag / lift measuring device is rotatable via a rotation drive control device. Strain-type three-component force detector for connecting and supporting a simple shaft, a signal processor connected to the strain-type three-component force detector via a DC-type strain amplifier, and a signal processed by the signal processor. And a control device for calculating a drag coefficient and a lift coefficient by calculating a drag coefficient and a lift coefficient.