JP2916676B2 - Tennis volley training equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a volley training tool for practicing a volley of tennis alone.

[0002]

2. Description of the Related Art Conventionally, to practice tennis alone, a ball is reflected on a vertical wall.

[0003]

In the above conventional practice,
The time it takes for the ball to hit the wall and fall to the ground is short,
He could practice ground strokes, but was not suitable for volley training. In addition, there was a problem that the ball returned after being bounced back had little change, and especially for advanced players, the practice was monotonous and not interesting.

[0004] It is an object of the present invention to provide a tennis volley training tool which is suitable for volley training and is interesting even for advanced tennis players and useful for improving the skill level.

According to the first aspect of the present invention, there is provided a tennis volley training device, wherein a rebound plate for repelling a ball volleyed by a trainer, and a pair of left and right arranged rearward of left and right edges of the rebound plate so as to be fixed to a building. With a vertical holding member , the flip plate is placed horizontally on the rear surface of the flip plate,
Jump when a tennis ball is dropped from a height of 1m
Reinforcing material is provided so that the bounce height is 0.2m or more.
To the left and right sides of the front projection provided at the top of the holding member.
The upper end of the rebound plate is formed by a screw member having a stretchable shaft.
Fixed, the lower part of the holding member and the lower end of the bounce plate
Between the screw and unscrew direction.
To adjust the tilt angle of the bounce plate to change the distance between them
The same member is interposed .

In order to fix the left and right vertical holding members to the building, for example, the left and right ends of the holding members are respectively arranged on the left and right sides.
A long hole may be provided, and each holding member may be attached to a wall or a pillar of the building by a bolt. When practicing volleying by slightly tilting the bounce plate upward, the ball that travels horizontally and hits the bounce plate bounces obliquely upward, increasing the time until falling, making it easier to practice volley. The angle that the bounce plate makes with the vertical plane is preferably 1 to 5 °,
2 to 3.5 ° is most preferred. In addition, as a hard tennis ball for confirming that the rebound height is 0.2 m or more, for example, a fault of Dunlop is good. By setting the rebound height to 0.2 m or more using the reinforcing material, the rebound amount of the ball by the rebound plate is secured.

[0007] The inclination angle of the bounce plate of this volley training tool
Can be changed as follows. First, the holding part
Loosen the screw member fixing the bounce plate to the material, and then
Screw-in or unscrew the screw member for adjusting the tilt angle
Turn in the direction. This allows the lower end of the bounce plate to be
Moving forward, i.e., the rebound plate is
Swing around the center. The angle of inclination of the bounce plate is the desired value
The spring plate is fixed to the holding member.
Screw. The screw member for adjusting the tilt angle
For example, one bolt and two lock nuts
The screw part at the tip of the bolt is
With two lock nuts and bolts
Bounce the base end of the rear panel at the lower left and lower right corners of the board.
By turning the two lock nuts,
The distance between the lower end of the bounce plate and the left and right holding members can be changed.
What should be done.

The volley practice of tennis according to the invention of claim 2
The tool is a bounce plate that bounces the ball volleyed by the trainer
And the bounce plate is held at an angle of elevation and the building or
And a holding member made as may be fixed on the ground, sloshing plate are those that are adapted to be warped to any concave and convex from horizontal cross section a straight line. In this way, the ball, which should go straight and return straight, changes back and forth in the left-right direction, so that even a tennis expert can perform a practice that is interesting and useful for improving the skill level.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. In this specification , left and right are shown in FIG.
4 are referred to as left and right, and the left and right in FIG.

FIGS. 1 to 7 show a tennis volley training tool according to the present invention. A horizontal rectangular bounce plate (4) for bouncing a volley ball by a trainee and a predetermined elevation angle are provided. A pair of left and right holding members that can be inclinedly held and fixed vertically to the building or the ground
(1)

The left and right holding members (1) have long holes (30) long at the upper and lower ends, and bolts (31) are formed in walls and columns.
Can be attached by The rebound plate (4) can be tilted to a predetermined elevation angle by adjusting the tilt angle adjusting bolts and nuts (20) and (23) provided near the lower ends of the left and right holding members (1) ( (See FIG. 4)
By adjusting the turnbuckle (21), it is possible to warp from a straight horizontal cross section to any of a concave shape (see FIG. 7) and a convex shape.

The bounce plate (4) is integrally provided with upper and lower rearward projections (5) along the upper and lower edges thereof. The upper and lower rear projections (5) are provided with five notches (24) at equal intervals from the approximately 1/3 position to the approximately 2/3 position from the left to facilitate warping into a concave or convex horizontal cross section. A pair of upper and lower edge reinforcing plates (15) sandwiching these cuts (24) from both upper and lower sides are attached by bolts and nuts (32). Of these upper and lower edge reinforcing plates (15), the bolt insertion holes at both ends are long slots on the left and right (33), and those between them are long slots on the front and back (34). .

Similarly, left and right rear projecting portions (6) are integrally provided along the left and right edges of the bounce plate (4). The left and right rear protruding portions (6) are provided with four notches (25) at equal intervals from approximately 1/3 to approximately 2/3 from the top to facilitate warping into a concave or convex vertical cross section. A pair of left and right edge reinforcing plates (16) sandwiching these cuts (25) from both left and right sides are attached by bolts and nuts (35). Of these left and right edge reinforcement plates (16), the bolt insertion holes at both ends are vertically long slots (36), and those between them are front and rear long slots (37). .

The upper ends of the left and right rear protruding portions (6) of the bounce plate (4) are respectively connected to bolts and nuts (1a) near the upper ends of the left and right holding members (1). 38). The bounce plate (4) can be swung about the axis of the bolt / nut (38) by loosening the bolt / nut (38).

The screw portion at the tip of the tilt angle adjusting bolt (20) is connected to two inwardly projecting ears (1b) with bolt insertion holes near the lower ends of the left and right holding members (1). 23). The base end of the tilt angle adjusting bolt (20) has a ring shape, and is applied to the lower left and lower right corners of the bounce plate (4) from the rear side, and the left and right rearward by bolts and nuts (39). It is fixed to the projection (6).
By turning the two lock nuts (23), the bounce plate
It is possible to adjust the distance between the lower end portion of (4) and the left and right holding members (1), and hence the inclination angle of the rebound plate (4).

A plurality of reinforcing members (7) (9) (10) (11) (12) are provided on the rear surface of the bounce plate (4). Reinforcement member (7)
(9) (10) (11) (12) are a circular center reinforcing plate (7) spot welded to the center of the bounce plate (4) and four frames arranged at the four corners of the bounce plate (4). And (9), (10), (11) and (12). The diameter of the central reinforcing plate (7) is approximately 1/3 of the average of the width and height of the bounce plate (4), and each frame-shaped reinforcing member
The width and height of (9), (10), (11) and (12) are approximately one third of that of the bounce plate (4).

A turnbuckle mounting plate (17) with a bolt insertion hole to which a front end of a turnbuckle (21) described later is mounted is fixed to the rear surface of the central reinforcing plate (7).

As shown in FIG. 2, the upper right frame-shaped reinforcing member (10) has a rectangular frame-shaped main body which abuts on the rear surface of the rebound plate (4).
(51) and upper, right, lower, and left rear projecting portions (52), (53), (54), and (55) provided integrally with the main body (51). The upper and right rear protrusions (52) (53)
(51) at the right corner. The lower and left rear projections (54) (55) are crossed near the left corner of the body (51). The lower left frame-shaped reinforcing member (11) is obtained by turning the upper right frame-shaped reinforcing member (10) upside down, and the upper left and lower right frame-shaped reinforcing members (9) and (12) correspond to the upper right frame. Reinforcing member (10)
Is a mistake.

Each of the frame-shaped reinforcing members (9), (10), (11) and (12) is provided with bolts and nuts (40) on the rear protruding portions (5) and (6) of the vertical and left and right edges of the rebound plate (4). And the upper and lower and left and right strips in which the frame-shaped reinforcing members (9), (10), (11), and (12) are arranged so as to surround the central reinforcing plate (7) and have wide surfaces facing each other. They are connected by plates (13) and (14).

A horizontal member (3) is passed between the upper and lower central portions of the left holding member (1) and the upper and lower central portions of the right holding member (1). The left and right ends of the cross member (3) have long bolt insertion holes (42) on the left and right sides, and are attached to the holding member (1) by bolts and nuts (43). A turnbuckle mounting plate (28) with bolt insertion holes is fixed to the left and right centers of the crosspiece (3), approximately one-third from the left and about one-third from the right of the crosspiece (3). , Spring mounting plate with bolt insertion holes (29)
Has been fixed.

As shown in FIG. 3, the turnbuckle (21) is composed of a central tubular body frame (56), right and left screws (57) and left and right screws (58) screwed into front and rear ends thereof, respectively. And lock nuts (59) and (60) for screws and left screws. The ring-shaped head of the right screw (57) at the front end of the turnbuckle (21) is attached to the turnbuckle mounting plate (17) of the central reinforcing plate (7), and the left screw (58) at the rear end of the turnbuckle (21). The ring-shaped head is mounted on a turnbuckle mounting plate (28) of the cross member (3).

Each of the left and right springs (22) is provided with a bolt insertion ring at both ends, and a rear end of the left and right springs (22) is a spring mounting plate.
(29), and the front end is attached to the left and right strips (14). Therefore, the left and right springs (22)
Through (14), all frame-shaped reinforcing members (9) (10) (11) (12)
Is pressed against the rear surface of the bounce plate (4).

An L-shaped steel is used for the holding member (1), a channel steel is used for the cross member (3), a 0.5 mm steel plate is used for the rebound plate (4), and reinforcing members (7) (8) In (9), (10), (11) and (12), a steel plate alone or a combination of a shaped steel plate and a steel plate is used.

When a steel plate having a thickness of 0.5 mm is used alone as the bounce plate (4), the bounce plate (4) itself is greatly deformed when hit with a tennis ball, so that the bounce amount is small, and Not suitable for practice. The central reinforcing plate (7) and the frame-shaped reinforcing members (8), (9), (10), (11), and (12) provide the rebound characteristics of the bounce plate (4). ) (8) (9) (10) (11) (12)
(4) shall be placed horizontally so that the rebound height when a hard tennis ball is dropped from a height of 1 m is 0.2 m or more, that is, 0.45 or more in terms of coefficient of restitution. Is preferred. Here, the used hard tennis ball is a fault of Dunlop Co., and the rebound height is about 0.5 to 0.55 on the concrete surface.
The thickness of the reinforcing members (7) (8) (9) (10) (11) (12) is 3 m
m or more is preferable. A more preferable value of the rebound height is
0.4-0.5 m (0.63-0.
71). By providing the reinforcing members (7), (8), (9), (10), (11), and (12), the material of the rebound plate (4) can be made of plastic or plywood other than steel. The dimensions of the bounce plate (4) are, for example, 1200 mm in width and 900 mm in height,
The distance between the lower end of the bounce plate (4) and the left and right holding members (1) set by the tilt angle adjustment bolts / nuts (20) and (23) is about 45 to 50 mm, which is converted to the tilt angle from the vertical plane. Most preferably, 2.9 to 3.2 °. In the case of the above dimensions, it is possible to practice at a position about 3.5 m away from the volley training tool for tennis, and a large practice area is not required.

When the rebound plate (4) is tilted and then deflected from a straight horizontal cross section to a concave or convex shape, the following procedure is performed.

The bolts and nuts (35) for attaching the left and right edge reinforcing plates (16) are tightened in advance, and the upper and lower edge reinforcing plates are
Loosely tighten the bolts and nuts (32) for attaching (15). Then, the body frame (56) of the turnbuckle (21) is rotated clockwise or counterclockwise. The bounce plate (4)
The four corners are supported by the left and right holding members (1).
Since it is prevented from bending in the vertical direction by the left and right edge part reinforcing plates (16), it is deformed into a concave or convex shape when viewed from a plane. At this time, as the cuts (24) of the upper and lower rearward projections (5) become narrower or wider, the upper and lower rearward projections (5) also deform into concave or convex shapes when viewed from a plane. The bolts and nuts (32) for attaching the upper and lower edge reinforcement plates are
It moves along the bolt insertion long holes (33) and (34) of 5) and does not hinder deformation. In this state, the installation is completed by tightening the bolts and nuts (32).

The forward and backward movement amount of the central portion (4c) of the rebound plate (4) is most preferably about ± 10 mm.
The a) and the right part (4b) have a width of 425 mm and bend about 1.35 ° from the extension of the central part (4c).

After loosely tightening the bolts and nuts (35) for attaching the left and right edge reinforcing plates (16) and the bolts and nuts (32) for attaching the upper and lower edge reinforcing plates (15), By rotating the body frame (56) of the buckle (21) clockwise or counterclockwise, it can be deformed into a concave or convex shape when viewed from the side. The principle will be described with reference to the side view of FIG. 8, the plan view of FIG. 9, and the side view of FIG. In these figures, the angle formed by the bounce plate (4) with the vertical plane is exaggerated.

FIG. 8 shows a bounce plate inclined with respect to the vertical.
This is a comparison of the motion of the ball bounced back by (4) with the case where the bounce surface is a vertical plane (V). In the same figure, when the ball launched from point A hits the bounce plate (4), which travels horizontally and is inclined at an angle α from the vertical plane (V),
It is rebounded obliquely upward by an angle 2α with respect to the horizontal, and returns near point A along a solid line. On the other hand, the ball launched from point A advances horizontally and
If it were to be bounced off by (V), the ball would be bounced horizontally and then fall back along the dashed line. Both the line and the line differ depending on the speed at which the ball hits the bounce plate (4), but are basically the same as those shown in the figure, and the ball is not slanted upward but obliquely upward or downward. Even if it does, that tendency does not change. As is clear from FIG. 8, the ball of the line formed by the vertical plane (V) falls to the ground quickly and is difficult to volley, whereas the ball of the line formed by the inclined rebound plate (4) is It will be much easier to volley. However, the direction of the ball being launched can swing up and down and left and right.To continue volleying, it is necessary to quickly switch between the forehand and backhand, or to perform fast footwork. Will be able to keep up and agility will be developed.

FIG. 9 shows the movement of the ball bounced off by the left portion (4a) of the bounce plate (4), which is concave when viewed from the plane, in comparison with the case where the bounce surface remains linear as viewed from the plane. It was done. In this figure, a point A is a reference vertical plane.
When the ball hit at right angles to (V) and horizontally hits the left part (4a) inclined by an angle β with respect to the center part (4c) parallel to the reference vertical plane (V), the ball bounces rightward. And returns to the reference vertical plane (V) along the line shown by the solid line.
Here, assuming that the rebound surface is not inclined, the ball will only return on the same course along the line shown by the chain line. When the angle β = 2.7 ° and the distance from the reference vertical plane (V) to the rebound plane is 3.5 m, the distance that the ball of the line shifts from side to side is 350 cm × tan 2.7 ° = 1
6.5 cm. On the other hand, in the case of a ball that has been hit horizontally at a predetermined angle θ from point A, the left side (4
In the case of a), the reference vertical plane is taken along the solid line.
Returning to (V), assuming the bounce surface is not inclined, the ball returns along the dashed line. Assuming that the distance from the reference vertical plane (V) to the rebound surface is D, and the incident angle when the rebound surface is not inclined is θ, the difference in the amount of change in the lateral direction is W = Dtan (θ + 2β) − Dtan θ
It is expressed as As is clear from FIG. 9, when the rebound surface is inclined, the amount of change in the lateral direction of the rebounded ball is larger than that of the non-inclined surface. Despite the practice, it is not monotonous, and it is possible to practice interesting and useful for improving the skill level. In the state shown in FIG. 9, if the player practiced by facing the center part (4c) of the bounce plate (4), if the ball hits the center part (4c) of the bounce plate (4), as shown in FIG. Bounced in the same way, left part (4a) of the bounce plate (4)
When the ball hits, the amount of movement of the ball to the left is smaller than usual. Thus, a beginner may practice in this manner. FIG. 9 shows a state in which the bounce plate (4) is deformed into a concave shape. However, when the bounce plate (4) is deformed into a convex shape, a variety of exercises can be performed on the same principle.

FIG. 10 shows a bounce plate which is concave when viewed from the side.
The movement of the ball bounced back by (4) (shown by a solid line) is compared with the case where the bounce surface is flat (shown by a chain line). In the same figure, the rebound angle when the ball hit horizontally hits the center of the rebound plate (4) is a line shown by a solid line and a line shown by a chain line,
The rebound angle of both is the same. When the ball hit downwards hits the lower part of the bounce plate (4), the bounce angle becomes a line shown by a solid line and a line shown by a chain line, and the larger the bounce plate (4) is concave. , Because it takes longer to fall, it is easier to hit. When the ball hit upward faces the upper part of the bounce plate (4), the bounce angle becomes a line shown by a solid line and a line shown by a chain line, and the smaller the bounce plate (4) is concave, the smaller the bounce angle. Because the ball does not rise too much, it is easier to hit. By bending up and down in this way, adjustment according to the level of the trainee can be performed.

In the above, by deforming the bounce plate (4) into a concave or convex shape, a high level of practice is possible even for advanced users. However, even if the volley technique is used in the state shown in FIG. Learning is possible. FIGS. 11 to 13 show tennis volley training tools exclusively used in the state of FIG.

A plywood having a thickness of 12 mm is used as the bounce plate (64). Rearward protruding portions (65) and (66) are provided on the upper and lower edges and on the left and right edges of the bounce plate (64). Since a sufficient repulsive force cannot be obtained with plywood alone, reinforcing cross members (67) having an L-shaped cross section are provided at the upper and lower edges of the rebound plate (64). Between them, reinforcing cross members (68) having a T-shaped cross section are provided at equal intervals. Further, a reinforcing vertical member (69) having an L-shaped cross section is provided on the left and right edges of the bounce plate (64).

The left and right holding members (1) and the tilt angle adjusting bolts / nuts (20) and (23) are the same as those in the first embodiment, and are denoted by the same reference numerals. The description is omitted.

The reinforcing horizontal members (67) and (68) in the tennis volley training tool of this embodiment have a rebound height of 0.2 m when the rigid tennis ball is dropped with the rebound plate (64) placed horizontally. As described above, it is provided so as to be 0.45 or more in terms of the coefficient of restitution, and by adjusting the repulsion force in this way, despite using plywood and having a simple configuration, High level practice is possible.

In the above two embodiments, the tilt angles of the bounce plates (4) and (64) are adjusted by adjusting the tilt angles of the bolts and nuts.
(20) (23) Adjustable, but bounce plate (4)
(64) may be fixed to the holding member (1) at, for example, an inclination angle of 3 °. In addition, bolts and nuts for adjusting the tilt angle
Instead of (20) and (23), turnbuckles may be used. A horizontally extending leg may be attached to the lower end of the holding member (1), and the leg may be fixed to the floor or the ground of the building.

[0037] According to the volley training device of tennis of the first aspect of the present invention, since the water humbly willing ball hits the splash plate is bounced diagonally upward, time until the fall is longer, become easier to volley practice . In addition, since the rebound amount of the ball by the splash plate by the reinforcing material is secured, and has a suitable Ri by the volley technology acquisition. Furthermore, the change of the tilt angle of the bounce plate is performed by adjusting the tilt angle.
It can be performed only by turning the adjusting screw member in the screw-in or screw-back direction.

According to the volley training tool for tennis according to the second aspect of the present invention, the rebound ball, which should go straight and return straight, changes back and forth in the left-right direction, which is also interesting for advanced tennis players. You can also practice to help improve your skill level.

[Brief description of the drawings]

FIG. 1 is a front view of a tennis volley training tool according to the present invention.

FIG. 2 is an exploded perspective view showing a main part of a tennis volley training tool, focusing on a rebound member.

FIG. 3 is an exploded perspective view showing a main part of a volley training tool for tennis, showing components that support a rebound member.

FIG. 4 is a side view of a volley training tool for tennis.

FIG. 5 is a sectional view taken along the line VV of FIG. 1;

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

FIG. 7 is a plan view of a volley training tool for tennis.

FIG. 8 is a side view showing the principle of the movement of the ball of the volley training tool for tennis according to the present invention.

FIG. 9 is a plan view showing the principle of the movement of the ball when the bounce plate is concave when viewed from a plane in the tennis volley training tool according to the present invention.

FIG. 10 is a side view showing the principle of the movement of the ball when the bounce plate is concave when viewed from the side in the tennis volley training tool according to the present invention.

FIG. 11 is a front view showing another embodiment of a tennis volley training tool according to the present invention.

FIG. 12 is a side view of the same.

FIG. 13 is a sectional view taken along the line XIII-XIII of FIG. 11;

[Explanation of symbols]

(1) Left and right holding members (1a) Front protruding ears (4) (64) Bounce plate (20) (23) Angle adjustment bolts and nuts (67) (68) Reinforcement cross members (69) Reinforcement vertical members

Claims (2)

(57) [Claims] 1. A rebound plate (64) for repelling a ball volleyed by a trainer, and disposed on the left and right edges of the rebound plate (64).
And a pair of left and right vertical holding members (1) adapted to be fixed to the building by means of a rebound plate (64).
Place the hardboard (64) horizontally and place a hard tennis ball 1m in height.
The rebound height when dropped from the position is 0.2m or more
Reinforcement members (67), (68), (69) are provided so that
The front projection (1a) provided at the top of (1) extends left and right.
The upper end of the rebound plate (64) by a screw member (38) having a shaft
Part is fixed, the lower part of the holding member (1) and the bounce plate
Between the lower end of (64) and
Bounce plate tilt that changes the distance between the two by turning
A volley training tool for tennis in which angle adjusting screw members (20) (23) are interposed . 2. A bouncing ball in which a trainee bounces a volleyed ball.
The bounce plate (4) and the bounce plate (4) are tilted and held at a predetermined elevation angle
And secured to the building or ground
Member (1) and a, sloshing plate (4) horizontal section linearly from the concave and volley training device of <br/> have Rute varnish either to be made as may warp convex.