JPH0417172Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field] This invention relates to a batting practice machine for baseball and tennis in which a ball is thrown out and the user practices hitting the thrown ball with a bat or a racket.

[Background technology]

2. Description of the Related Art Conventionally, there is a batting practice machine that rotates a pitching arm by driving a motor to store elastic force in a spring, and then releases the pitching arm to throw the ball. However, when the power was turned off after practice, the pitching arm sometimes stopped at the maximum spring biasing force. Therefore, when an impact is applied to the practice machine body during transportation, etc., the pitching arm rotates when pitching, posing the risk of injuring objects other than the batting practice machine or the body near the pitching mouth. Another problem was that when the power was turned on and batting practice started, the ball was suddenly thrown out, leaving the practitioner with no time to take a stance.

Therefore, as shown in Fig. 13, we proposed a system in which the power supply circuit for the motor 21 is provided with a position regulation switch SW ₂ for regulating the pitching arm angle in parallel with the power switch SW ₁ (Japanese Patent Application No. 122321/1982). . The position regulation switch _SW2 is turned off by being pushed by a contact provided on a gear that rotates the pitching arm. V is a power supply.

To explain the operation, when the power switch _SW1 is turned on, the motor 21 rotates and performs a series of throwing motions. When the power switch SW ₁ is turned off, the motor 21 continues to rotate while the position regulation switch SW ₂ is on, and when the position regulation switch SW ₂ is pressed by the gear for driving the pitching arm and turned off. The power will turn off. Therefore, if the motor 21 stops immediately after the power is turned off, the pitching arm will always stop at a constant angle, eliminating the above-mentioned problem of stopping the pitching arm in the state where the elastic force of the spring is stored.

However, even after the power is turned off, the motor 21 continues to rotate for some time due to inertia. As a result, the stopping position of the pitching arm is deviated, causing the above-mentioned problem of unexpected pitching motion. In extreme cases, the position regulation switch may turn on again and the motor may rotate again.

[Purpose of invention]

This invention ensures that the stopping position of the pitching arm is within a certain range when the power is turned off, and the pitching arm does not unexpectedly make a pitching motion when not in use, making it safe.
Another object of the present invention is to provide a batting practice machine that allows time for pitching when the power is turned on and practice is started.

[Disclosure of invention]

The batting practice machine of this invention includes a pitching arm that rotates and throws out a ball, a spring that rotates the pitching arm, a motor that rotates the pitching arm and stores elastic force in the spring, and its drive transmission means. , a power switch provided in the drive circuit of the motor; a position regulation switch connected in parallel with the power switch and turned off when the rotation angle of the pitching arm reaches a predetermined angle; and a position regulation switch provided in the drive circuit to control the motor. and a short circuit that short-circuits, and when the power switch and the position regulation switch are both in an OFF state, the motor acts as a generator to flow current to the short circuit and stop the pitching arm. It is something to do.

According to this configuration, when the power switch is turned off, the motor continues to rotate while the position regulation switch is on, and when the pitching arm reaches a predetermined angle, the position regulation switch is turned off and the motor power is turned off. It can be cut. Additionally, the motor that rotates due to inertia becomes a generator and current flows through the short circuit, which causes current to flow in the opposite direction to the motor, generating a force that causes the motor to rotate in the opposite direction. The inertial rotation of the motor can be stopped immediately.

Therefore, when the power switch is turned off, the pitching arm always stops at a constant angle. Therefore, by appropriately setting the stopping angle, the pitching arm can always be stopped in a state in which the spring force is released, thereby preventing the pitching arm from unexpectedly pitching due to impact during transportation. Furthermore, the next time the power switch is turned on, pitching will not start suddenly, giving you more time to catch the ball.

Embodiment A first embodiment of this invention is shown in FIGS. 1-8.
In this embodiment, as shown in FIG. 1, a short circuit D serving as an arm brake means is provided in the power supply circuit of the motor 21. As described later, the motor 21 is
This is to rotate the pitching arm and accumulate elastic force in the spring. V is the power supply, _SW1 is the power switch, and P is the AC adapter connection terminal. Position regulation switch SW ₂ for arm angle regulation in short circuit D
and a current limiting resistor R for suppressing the current level of the short circuit D. The position regulating switch SW ₂ is provided in parallel with the power switch SW ₁ and closes the short circuit D in the off state.

Note that FIG. 1a shows a state in which the power switch SW ₁ is turned on and the motor 21 is operating (FIG. 5,
6). FIG. 1b shows a state in which the position regulation switch _SW2 is turned off after the power switch _SW1 is turned off, and the motor 21 is stopped (the state shown in FIGS. 7 and 8).

Explain the overall structure. In FIG. 3, reference numeral 1 denotes a main body case, which has a ball throwing opening 2 on the front and a ball supply section 11 on the side.
A first ball stocker 9 formed of a pipe material is connected to this, and a second ball stocker 9 is connected to the first ball stocker 9.
A ball stocker 10 is connected to the ball stocker 10. 12 is a leg, and 13 is a feed cover.

The main body case 1 is divided at the center into a left main body cover 1A and a right main body cover 1B, and a front cover 1.
C is provided. The left main body cover 1A and the right main body cover 1B are assembled as shown in FIG. That is, a pair of nuts 41 and 42, which are integrally connected by a connecting piece 44, are fitted and fixed into the mounting holes 5 formed at the bottom front ends of the left main body cover 1A and the right main body cover 1B, respectively, and the left main body cover 1A The peripheries of the openings of the right main body cover 1B and the right main body cover 1B are overlapped and fixed with screws 43. Said pair of nuts 4
1 and 42 are connected by a connecting piece 44,
Unlike the case where separate nuts are fixed to the left main body cover 1A and the right main body cover 1B, the nuts do not come off or rattle, and furthermore, the main body case 1 can be prevented from opening. The pair of nuts 41 and 42 each have a pair of legs 4 with rubber feet 47 attached to their tips and screws formed on the circumferential side.
5 and 46 are screwed on. The legs 45 and 46 are attached to the main body case 1 by changing the amount of protrusion from the main body case 1.
The inclination angle of the ball M is adjusted, and the throwing angle of the ball M is adjusted.

Explain the internal structure. A ball feeding port 3 is provided on the side surface of the right main body cover 1B, and a pair of parallel guide rails 4 for receiving balls M fed therefrom are provided on the left main body cover 1A and the right main body cover 1B. Further, the pitching arm 6, the ball setting arm 7, and their drive mechanism are housed together with the frame 8. The pitching arm 6 has a pair of parallel leg pieces 6A and 6B (fourth leg pieces) made of wire springs.
(Figure). One end of each leg piece 6A, 6B is inclined in the rotating direction and connected, and the ball M is connected between the parallel part of both leg pieces 6A, 6B and the connecting part.
A ball mounting portion 6C is configured to hold the ball at a point. A stepped portion 51 for fixing the damper stopper 80 is formed near one end of each leg piece 6A, 6B, and a bent portion 52 for fixing the cam follower shaft 17 on which the cam follower 16 is rotatably mounted is formed near the other end. There is. The cam follower shaft 17 is disposed at the bent portion 52 and is pressed and fixed to the pitching arm 6 by a click spring 53. The damper stopper 80 is disposed on the stepped portion 51 and is fixed to the pitching arm 6 by welding and caulking. The damper stopper 80 serves to stop the rotation of the pitching arm 6 by colliding with the damper 31 when the pitching arm 6 moves while being accelerated to throw the ball M. The damper stopper 80 is located between the cam follower 16 and the ball rest 6C. The surface of the damper 31 that collides with the damper stopper 80 is an uneven surface, as shown in FIG. 5, to reduce the impact upon collision. The damper 31 is made of a rubber-based material, and by providing a through hole 31a (FIG. 5) as necessary, it is possible to further soften the impact and reduce the impact noise. Coil springs 14 and 15 constituting ball throwing springs are integrally connected to the other ends of each of the leg pieces 6A and 6B.
The coil springs 14 and 15 are made of wire springs like the leg pieces 6A and 6B, and are wound clockwise and counterclockwise, respectively. The pitching arm 6 is a coil spring 1
A pipe-shaped support shaft 1 that comes into contact with the inner circumferential surfaces of 4 and 15
Both ends of the support shaft 18 are fixed to a pair of opposing side walls of the frame 8, respectively. Each free end 14A, 1 of the coil spring 14, 15
5A are engaged in hemispherical recesses 28 and 29 formed at the edge of the connecting piece 35 of the frame 8, respectively. A plurality of recesses 28 and 29 are formed symmetrically at positions corresponding to the free ends 14A and 15A of the coil springs 14 and 15, respectively.

A drive device for rotating the pitching arm 6 will be explained. Cam 1 in rolling contact with the cam follower 16
9 has a diameter that gradually increases in the direction of rotation, and becomes discontinuously small along the way. The drive of the cam 19 is
This is done by a motor together with the ball setting arm 7. This drive transmission system will be explained. frame 8
A geared motor 21 (FIG. 4) in which a motor and a speed reducer are integrated is fixed to , and a small gear 23 is press-fitted and fixed to the output shaft 21 a of the geared motor 21 . Further, a large gear 26 having a protrusion 25 on the cam shaft 24 for operating the cam 19 and the ball set arm 7 is provided.
are connected and rotatably fitted to the camshaft 24. By installing the camshaft 24 in this way, the large gear 26 meshes with the small gear 23. In addition,
The ball set arm 7 is for feeding the balls M one by one from the ball supply section 11 (FIG. 3).

A ball set arm 7 is rotatably installed on the right main body cover 1B at a boss portion 50 (FIG. 4). A ball setter 100 is fixed to the ball set arm 7 on the outside of the right body cover 1B with a pin or the like so as to be integrated with the ball set arm 7. Further, the ball set arm 7 is always pressed in the F direction by a set arm spring 151 at the boss portion 50 of the right main body cover 1B. Further, the other end of the ball set arm 7 to which the ball setter 100 is fixed is rotatably fitted into the boss portion 101a of the ball feeding case 101. The other end of the ball set arm 7 extends above the set and engages with the protrusion 25 of the large gear 24 during assembly. The ball setter 100 is formed by bending a pair of leg pieces 100A and 100B in a V-shape in opposite directions of ball movement relative to the fixed stopper 110. In addition, in Fig. 8,
A indicates the width through which the ball M passes.

The frame 8 is provided with the above-mentioned normally closed position regulating switch SW ₂ , and the position regulating switch SW ₂ is operated by a contact protruding wall 92 provided on the large gear 26 . Note that the power switch SW ₁ has a knob 90.

Operation Next, the operation will be explained based on FIGS. 5 to 8. As shown in FIG. 5, when the ball M is sent inside from the ball feeding port 3, the ball M is
It is held by the ball rest part 6C at the tip of the ball. cam 1
9 rotates in the direction of the arrow in Fig. 5, and the cam follower 1
The pitching arm 6 is connected to the coil springs 14 and 15 through the coil springs 14 and 15.
The coil spring 14 is driven in the direction of winding the coil spring 14,
15 stores elasticity. FIG. 6 shows the state of the pitching arm 6 just before the ball M is thrown out.
When the cam follower 16 comes off the maximum radius of the cam 19, the elastic force stored in the coil springs 14 and 15 of the pitching arm 6 is suddenly released, and the pitching arm 6
is kicked out while holding the ball M for 3 points.
Pitching arm 6 moves while holding ball M
When it comes into contact with the damper 31, the ball suddenly stops moving, and only the ball M is thrown out with an initial velocity accelerated by the energy of the coil springs 14 and 15.

Pitching is started and stopped by turning power switch SW ₁ on and off. The position regulation switch SW ₂ is turned off by being pushed by the contact wall 92 provided on the large gear 26 every time the pitching arm 6 makes one rotation, but the motor 21 is not driven while the power switch SW ₁ is on. I can continue.

When power switch SW ₁ is turned off, position regulation switch SW ₂ is turned on, so motor 2
1 continues to rotate without stopping. Figures 5 and 6
The figure shows a state in which the power switch SW ₁ is off, the position regulation switch SW ₂ is on, and the motor 21 is rotating. After the motor 21 continues to rotate and the pitching arm 6 throws out the ball M, the movable piece 91 of the position regulation switch SW ₂ is pushed by the contact projection wall 92 of the large gear 26, and the position regulation switch SW ₂ is turned off. Therefore, the motor 21 stops (FIG. 7). At this time, the motor 21 attempts to continue rotating for some time due to inertia, but stops instantaneously as follows. That is, when the motor 21 rotates due to inertia (states shown in Figures 7 and 1b), it becomes a generator and the direction of the current changes from I ₁ to I ₂ , so a force that rotates in the opposite direction is generated. It turns out. Therefore, the motor 21 instantaneously stops rotating. Figure 2 a, b
indicates the current of the motor 21. As shown in the figure, the time t ₂ during which the motor 21 continues to rotate after the power is turned off due to the generation of current in the opposite direction is longer than the time t ₂ during which the conventional example in FIG. 13 continues to rotate due to inertia (Figure 14). significantly shorter.

In this way, when the position regulating switch SW ₂ is turned off, the motor 21 stops instantaneously, so the pitching arm 6 always stops with the energy of the coil springs 14 and 15 released. Therefore, unexpected pitching motions due to shocks during transportation, etc. are prevented, and when the power switch SW ₁ is turned on next time, pitching is not suddenly started, and there is enough time to catch the ball. In addition, since the pitching arm 6 stops at a fixed position, the ball setting arm 7
Since the ball always stops at a fixed position, the reliability of the ball feeding operation is improved. That is, conventionally, due to the inertia of the motor 21, the ball setter 100 would stop while the waiting ball M was being sent from the ball setter 100, and the next ball M would be caught by the ball setter 100, and the operation would start again. Sometimes the ball could not be fed. However, in this embodiment, such problems are eliminated.

Note that the resistance R of the short circuit D is for current control, and may be set within a range that does not exceed the full width of the contact protruding wall 92 of the large gear 26. By suppressing _I2 , Burnout of the brushes of the motor 21 due to rush current and damage to gears and bearings due to reversing force can be reduced.

FIG. 9 shows another embodiment. In this example, the short circuit C of the motor 21 serving as the braking means is always kept closed. In this case, the constant current is the sum I ₁ +I ₃ of the current I ₁ flowing through the motor 21 and the current I ₃ flowing through the resistor R, which has the disadvantage of shortening the battery life. However, if you use an AC adapter as the power source, you don't have to worry about its lifespan.
Effective. The rest is similar to the first embodiment.

In the first and second embodiments, a cam 19 whose diameter gradually increases and becomes discontinuously small in the middle is provided on the motor shaft, and the cam follower 16 provided on the pitching arm 6 is pushed by the cam 19. , a batting practice machine that rotates the pitching arm and stores elastic force in the coil springs 14 and 15; It may also be used as a batting practice machine that opens and throws out the ball.

10 to 12 show a third embodiment. In this example, the shape of the cam 19' is shown by the solid line in FIG. 12. In other words, the conventional cam 19 has a diameter that does not touch the cam follower 16 at the small diameter portion (range of angle θ ₂ ) immediately after the discontinuous portion of the cam surface, as shown by the broken line in the same figure. Cam follower 16 as shown by the solid line
This part has a diameter that comes into contact with the brake member, and this part constitutes the brake means. Specifically, the diameter of the cam 19' is set as _R2 in the angle range of _θ1 , and _R3 is set as the diameter from the angle of _θ1 to the angle of _θ2 . _R3 > _R2 . The motor drive circuit is similar to the example shown in FIG. In addition, the first
FIG. 0 shows a state in which the power switch SW ₁ is turned off, the position regulation switch SW ₂ is turned on, and the motor 21 (FIG. 13) is operating. Similarly, FIG. 11 also shows a state in which the motor 21 is operating. Figure 12 shows that after the power switch SW ₁ is turned off, the position regulation switch SW ₂ is turned off, and the motor is turned off, the motor 2
1 has stopped rotating and the pitching arm 6 has stopped.

The operation of this example will be explained in comparison with a conventional example.
In the conventional example in which the cam 19 is formed as shown by the broken line in FIG.
and the cam follower 16 of the pitching arm 6 _.
There is a gap of −R ₁ and this gap exists between angles θ ₂ . Therefore, during this time, there is no load on the motor 21, and even if the power to the motor 21 is turned off, the cam 19 and the large gear 26 can rotate within the angle range of θ ₂ due to inertial force.

In contrast, in this embodiment, the cam follower 16 comes into contact with the cam follower 19' immediately after pitching, so the large gear 2
6 and cam 19 resist the force of rotation due to inertia force, and come to a stop at the angle θ ₁ mentioned above. Here, the distance R ₂ is slightly smaller than the distance from the cam center to the cam follower 16, and is designed to prevent the cam follower 16 from colliding with the small diameter portion of the cam 19' when the step 16 comes off the cam 19' during pitching. , cam follower 16
and large gear 26 from being damaged. Therefore, the rotation of the motor 21 is stopped during the angle _θ1 .

In this way, by making the cam shape as described above, the accuracy of stopping the entire device in a fixed position is improved,
Unexpected throwing by the pitching arm 6 is eliminated,
In addition, the ball feeding state can be started at the same time as the pitching arm 6 moves, and even when the pitching arm 6 stops due to an overrun, the ball setting arm 7 does not stop in the activated state, and a reliable ball feeding operation can be realized. .

In addition, in the conventional example in which the cam 19 is formed as shown by the broken line in FIG. 12, the contact type is Projection wall 92
was formed to be somewhat long. However, there are variations in the amount of movement due to inertia, and it is necessary to make the range of the contact protruding wall 92 as large as possible for safety. This is because if the contact protruding wall 92 is short, the contact protruding wall 92 may overrun, making it impossible to shut off the position regulating switch SW ₂ , and the device will not stop. However, if the contact protruding wall 72 is made too long, the stopping position will vary depending on the cut-off position of the power switch _SW1 of the device, and drawbacks will also arise from other directions. In other words, the pin 25 provided on the large gear 26 operates the ball set arm 7 for supplying the ball M, and from the viewpoint of ball supply, the ball M is supplied at the same time as the pitching arms 6A and 6B operate. It is best to
It is better that the gap between the two is as small as possible. This is where the absurdity arises. In other words, in the conventional example, it is desirable to lengthen the contact wall 92 in order to stop the equipment, but
In this case, the pin 25 must also be formed at a distance from the ball throwing position in consideration of the inertia of the motor, and from the standpoint of ball supply, the contact protruding wall 92 must be made as short as possible and stopped at a fixed position. It goes against the grain. This embodiment can eliminate both of these absurdities.

[Effect of idea]

In the batting practice machine of this invention, even when the power switch is turned off, the pitching arm rotates until the position regulation switch is turned off. Furthermore, when the power switch and the position regulation switch are turned off, the motor rotating due to inertia becomes a generator, and current flows in the opposite direction to the motor in a short circuit. This generates a force that causes the motor to rotate in the opposite direction, making it possible to instantaneously stop the motor. Therefore, the stopping position of the pitching arm can be secured within a certain range when the power is turned off, and the pitching arm will not unexpectedly make a pitching motion when not in use, making it safe. This has the effect of giving you more time before pitching.

[Brief explanation of the drawing]

Fig. 1a is an electric circuit diagram showing the motor in operation according to the first embodiment of this invention, Fig. 1b is an electric circuit diagram when the motor is stopped, and Fig. 2 is an explanation of the motor drive circuit current. Figure 3 is a perspective view of the whole, Figure 4 is a cutaway front view,
Fig. 5 is a cutaway side view with the power switch turned off and the position control switch turned on, Fig. 6 is a cutaway side view immediately before pitching, and Fig. 7 is a cutaway front view immediately after pitching. , FIG. 8 is an explanatory diagram of the operation on the ball supply side, FIG. 9 a is an electric circuit diagram showing the motor in operation in the second embodiment, and FIG. 9 b is an electric circuit diagram showing the motor in a stopped state. 10 is a cutaway side view of the power switch off and position regulation switch of the third embodiment, FIG. 11 is a cutaway side view of the state immediately before the pitching operation, and FIG. 12 is a cutaway side view of the state immediately after the pitching operation. A broken side view, Fig. 13 is an electric circuit diagram of the conventional example, Fig. 1
FIG. 4 is an explanatory diagram of its operation. 1...Main case, 2...Ball throwing opening,
4...Guide rail, 6...Pitching arm, 7...
Ball set arm, 8... Frame, 14, 1
5...Coil spring, 16...Cam follower, 1
9, 19'...cam, 21...motor, 26...
Large gear, M...Ball, SW ₁ ...Power switch,
SW ₂ ...Position regulation switch, D...Short circuit (braking means).

Claims (1)

[Claims for Utility Model Registration] (1) A pitching arm that rotates and throws out a ball, a spring that rotates the pitching arm, a motor that rotates the pitching arm and stores elastic force in the spring, and its drive. a transmission means, a power switch provided in the drive circuit of the motor, a position regulation switch connected in parallel with the power switch and turned off when the rotation angle of the pitching arm reaches a predetermined angle, and a position regulation switch provided in the drive circuit. and a short-circuit circuit that short-circuits the motor, and when the power switch and the position regulation switch are both in an OFF state, the motor acts as a generator to flow current through the short-circuit circuit and stop the pitching arm. A batting practice machine featuring (2) The drive transmission means includes a cam that is attached to the output shaft of the motor and whose diameter gradually increases in the rotation direction and discontinuously decreases in diameter along the way, and a cam follower that is provided on the arm and contacts the cam. A batting practice machine according to claim (1), wherein the cam is shaped such that a small diameter portion immediately after the discontinuity comes into contact with the cam follower.