JP5999616B2 - Throwing machine - Google Patents

Description

  The present invention relates to a ball thrower that is effective when used for practicing ball sports such as baseball, table tennis, tennis, soccer, and volleyball.

For example, a baseball pitching machine will be described as an example. A roller-type pitching machine that can throw a change ball such as a straight ball, a curve, and a shoot at an arbitrary ball speed (over 80 to 150 km / h) is known.
However, pitching such as a straight ball or a curve is one in which the ball rotates in the pitching direction.
That is, the rotation axis of the ball is in a plane perpendicular to the batter.
However, such a ball type in which the rotation axis of the ball is only in a plane orthogonal to the pitching direction is insufficient as a practice pitcher, and a rotation in a predetermined twisting direction is added to the ball shooting direction. Non-rotating ball types called gyro balls, cut balls, knuckle and fork balls are also required.
Patent Documents 1 and 2 disclose two-roller type and three-roller type pitching machines in which the rotation shaft of the roller is twisted and arranged at a predetermined angle with respect to the ball firing direction.
However, in the two-roller type disclosed in Patent Document 1, the rotating shaft of the firing roller is twisted, but in reality, the friction between the ball and the roller surface is considered even if it is theoretically possible. As a result, the torsional component of the rotational force that imparts torsion was reduced by slippage between the ball and the roller surface, and almost no torsional rotation was imparted to the ball.
Further, in the three-roller type disclosed in Patent Document 2, it is not easy to provide a torsion mechanism to all three rollers.
Actually, in the pitcher, not only the gyro ball but also the ball that rotates in the pitching direction such as a straight ball or a curve is required, and the mechanical structure is twisted because the roller of the twisting mechanism is twisted back in the opposite direction. It becomes complicated.
In addition, the rotational speed of the roller for firing the ball and the number of gyro rotations in the twisting direction cannot be arbitrarily changed.
Patent Document 3 discloses a technique in which a rotating cylindrical portion is provided separately from the firing roller, but the entire three firing rollers must be rotated, the structure becomes complicated, and the gyro rotation speed in the torsional direction is limited. However, there is a problem that it is difficult to raise the pitcher's throwing rotation.

Japanese Patent No. 3986124 JP 2006-67735 A JP 2010-273930 A

  An object of the present invention is to provide a pitcher that can arbitrarily set rotation in a pitching direction and rotation in a torsional direction on a ball to be launched.

The throwing machine according to the present invention rotates at a predetermined twist angle (γ) with respect to the rotation direction of the shooting roller and a plurality of shooting rollers rotating in the direction in which the ball is pinched and discharged, and contacts the outer peripheral surface of the ball The predetermined twist angle (γ) can be variably adjusted from γ = 0 ° to a predetermined range, and the ball to be fired can be imparted with either torsional rotation or non-rotation. Features.
The pitcher according to the present invention is not limited to the baseball pitch described above as an example, and can be applied to all ball games.
For example, some table tennis ball lines are subject to a large gyro rotation, and the ball may be small in size.
The pitcher according to the present invention can cope with such a ball type.
Further, it can be used for launching a ball in various ball games such as launching a soccer ball larger than a baseball.
In this specification, the gyro roller refers to a roller that rotates in a direction different from that of the firing roller and applies a torsional force to the ball or does not rotate.

As a specific configuration example of such a throwing machine, two firing rollers are disposed to face each other, and two gyro rollers are disposed to face each other in a direction substantially perpendicular to the two opposed firing rollers. There are three or more firing rollers around the circumference of the ball in the firing direction, and at least one gyro roller is provided between the firing rollers.
The launch roller is two rollers facing each other, or three or more rollers around the ball, and a plurality of rollers rotating in the ball launch direction by throwing the ball into the space formed in the center The ball is sandwiched by force and fired forward.
Therefore, at least the outer peripheral portion of the firing roller is preferably made of a material having rubber elasticity, and preferably has compressibility and elasticity.
The diameter of the firing roller is preferably about 2 to 8 times the diameter of the ball, although it depends on the size and type of the target ball.
For example, in the case of a baseball, the diameter is preferably in the range of 200 mm to 450 mm.
The outer peripheral surface of the firing roller is preferably a flat surface or a gentle shape with a radius of curvature of 80 mm or more.
On the other hand, the gyro roller makes contact with the side surface of the ball by friction when the ball passes between the firing rollers, and applies a rotational force in a torsional direction to a right angle direction to the ball to be fired, or the firing ball. The frictional force is applied so as to be non-rotating.
Therefore, the gyro roller is disposed so as not to interfere with the firing roller.
Since the gyro roller contacts the outer peripheral surface of the ball at a predetermined twist angle with respect to the rotation direction of the firing roller, the outer peripheral surface is preferably a curved surface having a convex direction, and is about 1/2 to 4 times the ball radius. The diameter of the gyro roller is preferably smaller than that of the firing roller.

  In the present invention, in addition to the firing roller that rotates to fire the ball, a gyro roller that rotates in a torsional direction or does not rotate when the ball is fired is provided in an independently controlled state. Rotating balls and non-rotating balls can be fired.

The example of arrangement | positioning of the roller of the pitcher which concerns on this invention is shown. (A) is a perspective view, (b) shows a front view. An example of the twist angle of the gyro roller with respect to the firing roller viewed from the front is shown. (A) is an example of twist angle γ = 0 °, (b) is an example of twist angle γ = 30 °, and (c) is an example of twist angle γ = 90 °. The relationship between the twist angle of the gyro roller and the rotational force of the ball is shown. (A) is an example of γ = 0 °, (b) is γ = 30 °, and (c) is an example of γ = 90 °. A pitching simulation result when a combination of two firing rollers and two gyro rollers is used is shown. An example of a structure in which three firing rollers and one gyro roller are combined is shown. An example in which one gyro roller is twisted with respect to three firing rollers is shown. (A) shows an example of twist angle γ = 90 °, and (b) shows an example of γ = 45 °. A simulation result in the case of combining three firing rollers and one gyro roller is shown.

1 to 4 show an example in which two opposing gyro rollers 21 and 22 are used for two opposing firing rollers 11 and 12.
Both gyro rollers have a structure capable of varying the angle γ from 0 ° to 90 ° in the XY plane.
FIG. 2 is a configuration example of a pitching machine viewed from the front of two opposed firing rollers 11 and 12. The firing rollers 11 and 12 have motors M ₁ and M ₂ respectively having rotation axes d ₁ and d _2. They are arranged in parallel.
Although not shown, the distance between the two firing rollers 11 and 12 is controlled to be adjustable.
Although two gyro rollers 21 and 22 are arranged opposite to each other in a direction substantially orthogonal to the two firing rollers 11 and 12 and are rotationally controlled by motors M _j1 and M _j2 , the illustration is omitted. 22 and the torsion angle γ of the rotation axes d _j1 and d _j2 are controlled to be adjustable up to γ = 0 to 90 ° with respect to the arrangement surface of the two firing rollers.
The gyro ball can be arbitrarily selected from the three elements (ball speed, rotation axis, spin number) of the flying ball by throwing the ball at different angles such as γ = 30, 60, 90 °, etc.
Moreover, general changing spheres such as a straight sphere and a curve can be obtained by eliminating the twist angle.

A pitching simulation was performed with analysis software (ANSYS / LS-DYNA) using the structural example of the pitcher.
The result is shown in FIG.
The ball is a hard baseball, and the rotation speed of each firing roller is N ₁ = N ₂ = 2050 [min ⁻¹ ], and the rotation speed of the opposing gyro roller is N _J1 = N _J2 = 5467 [min ^{− 1} ].
By setting the rotation speeds of the firing roller and the gyro roller in this way, the outer peripheral speeds V _R of the four rollers were set to be equal to 34.35 m / s.
FIG. 4 shows that a non-rotating ball with almost no spin is thrown when γ = 0 °, and a counterclockwise gyroball is thrown at γ = 30 ° and 90 °.
Of course, the spin amount of each ball can be changed by adjusting the number of rotations of each roller. Note that the rotational axis of γ = 30 ° and 90 ° is in the direction directly in front of the batter, resulting in a very beautiful gyro ball.
Comparing the spin amount S between γ = 30 ° and 90 °, γ = 90 ° is higher.
This is of course considered to be due to the greater spin force acting at γ = 90 °.
On the other hand, the ball speed V decreases as γ increases.
This is presumably because the translational force of the ball decreases as the spin force increases.
As a result of the pitching simulation, it became clear that a two-roller type pitcher with a two-gyro roller can throw a beautiful gyro ball by adding a twist angle γ.
Of course, if the number of rotations of the four rollers is changed in the present pitching machine, a changing ball such as a straight ball or a curve can be thrown.
In addition, when the two gyro rollers are provided so as to face each other, the ball is supported by the rotational force in the twisting direction from both sides, so that the torsional frictional force is effectively transmitted to the ball.

5 and 6, three firing rollers 11, 12, and 13 are arranged around the circumference, and a gyro roller 21 for throwing a gyro ball is provided on the upper portion. The rotation angle (torsion angle; γ) and the rotation speed N of this roller are provided. By changing _J , the rotation axis of the ball can be set in any three-dimensional direction, and the gyro rotation number (spin number) can be arbitrarily given by the rotation number of the gyro roller.

For example, even with a gyro ball having the same ball speed, a gyro ball having a different spin number can be thrown by changing the rotation speed of the gyro roller.
It is also possible to throw a straight ball or a curve other than the gyro ball system.
FIG. 7 shows the result of the pitching simulation performed using the analysis software (ANSYS / LS-DYNA).
The ball is a hard baseball, and the rotation speeds of the three firing rollers are N ₁ = N ₂ = N ₃ = 2050 [min ⁻¹ ] and the rotation speed of the gyro roller N _J = 5467 [min ⁻¹ ]. did.
This roller rotation speed was set equal to the peripheral speed V _R = 34.35 m / s of the four rollers.

As a result, it can be seen that a straight ball with little spin can be thrown when γ = 0 °, a reverse-spin cut ball is thrown when γ = 45 °, and a counterclockwise gyroball is thrown when γ = 90 °.
Of course, the spin amount of each ball can be changed by adjusting the number of rotations of each roller.

1 Ball 11 Firing Roller 12 Firing Roller 21 Gyro Roller 22 Gyro Roller

Claims (3)

A plurality of firing rollers that rotate in the direction of pinching and firing the ball;
A gyro roller that rotates at a predetermined twist angle (γ) with respect to the rotation direction of the firing roller and contacts the outer peripheral surface of the ball,
The predetermined twist angle (γ) can be variably adjusted from γ = 0 ° to a predetermined range,
A pitcher capable of imparting both torsional rotation and non-rotation to a ball to be fired. The firing roller has two firing rollers arranged opposite to each other,
2. The pitcher according to claim 1, wherein the two gyro rollers are disposed so as to face each other in a direction substantially orthogonal to the two opposing firing rollers.   2. The pitcher according to claim 1, wherein there are three or more firing rollers around the circumference of the ball in the firing direction, and at least one gyro roller is provided between the firing rollers.