JPS6154426B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an automatic ball throwing device used for tennis practice.

The ball cutting section of this type of automatic ball throwing device uses a rotating plate having a plurality of ball cutting holes or notches, and the balls that have entered the holes or notches of the rotating plate are dropped one by one from the discharge port by their own weight or are transported by air. There is something that is sent to the ball launcher.

However, since the rotary plate is a rigid body, the balls that have entered the holes or notches may get caught between the rotary plate and the discharge port when being discharged. The higher the rotational speed of the rotary plate, the higher the probability of such jamming.

Further, the time during which the cut balls are transported by air or their own weight to the firing section is unstable depending on the diameter of the ball and the state of the progress of transport, and the firing interval is not constant. Furthermore, the mechanism was complex, prone to breakdowns and wear, lacked durability, and was expensive.

In view of the above-mentioned conventional drawbacks, the present invention reliably cuts out the balls, feeds the balls directly to the firing wheel so that the firing interval is constant, and
To obtain an automatic ball throwing device which can arbitrarily adjust the firing interval and is equipped with a durable and inexpensive ball cutting device.

Hereinafter, the present invention will be explained in detail with reference to an embodiment shown in the drawings.

In the embodiment shown in FIGS. 1 to 3, reference numeral 1 denotes a firing section main body of an automatic ball throwing device, and within this firing section main body 1 a firing tube 2 is fixedly installed. The firing tube 2 has wheel insertion holes 3, 3 formed at the upper and lower portions of the center, and a ball inlet 4 at the upper surface near the rear. 5
is a hose that sequentially drops the balls 6 in an aligned state into the ball inlet 4 by their own weight,
This hose 5 is attached to the ball inlet 4 by a hose joint 7. Reference numeral 8 denotes a check plate that is attached to the rear end of the firing tube 2 and prevents the ball 6 falling from the ball inlet 4 from moving in the counter-launching direction. Reference numerals 9 and 9 denote a pair of upper and lower wheels rotatably provided in a direction in which a ball can be fired into the firing section main body 1, which is partially inserted into the wheel insertion holes 3 and 3 of the firing tube 2. The upper and lower wheels 9, 9 are fixed to shafts 11, 11 of upper and lower drive motors 10, 10 fixed to the ejecting section main body 1 by set screws 12, 12. Reference numeral 13 denotes a ball cutting device, and this ball cutting device 13 is formed in a notch 14 formed on the side surface of the firing tube 2 from the rear to approximately the center, and in the check plate 8 at a position corresponding to the notch 14. a cutout portion 15 , a cutout motor mounting plate 16 fixed to the outer surface of the firing section main body 1 , and a cutout motor 17 fixed to the cutout motor mounting plate 16 .
and the cutout portions 14, 1 fixed to the rotating shaft 18 of the cutting motor 17 with a set screw 19.
5, and has a plurality of blades 20, five blades 20 in this embodiment, spaced apart so that one ball 6 can fit therein.

In the above configuration, the balls 6 are sequentially placed inside the hose 5.
and upper/lower drive motors 10,
10 and the cutting motor 17 are driven at a predetermined speed, the upper and lower wheels 9, 9 and the cutting blade 21 are driven to rotate in the direction of the arrow, as shown in FIGS. 2 and 3. Therefore, the blades 20 of the cut-out blades 21 ensure that only one ball 6 enters the firing tube 2 from the ball inlet 4 due to its own weight from inside the hose 5 and is placed between the upper and lower wheels 9 and 9. pushed into. For this reason, the ball 6 pushed between the upper and lower wheels 9, 9
9 is fired because it is rotating at high speed.

Note that the inner diameter of the launch tube 2, the inner diameter of the ball inlet 4, and the dimensions between the blades 20 of the cut-out blade 21 are each slightly larger than the diameter of the ball 6 without getting caught and two balls 6 entering. It is set.

As is clear from the above description, the present invention has the following effects.

(1) The ball that falls into the launch tube from the ball inlet of the launch tube can be reliably pushed between a pair of wheels.

(2) Since the ball is pushed between a pair of wheels by the rotation of the cut-out blade, there is no failure and it has excellent durability.

(3) Simple structure and low cost.

(4) Since the blade spacing of the cut-out blades is made large enough to accommodate one ball, it is possible to reliably push the balls one by one between the pair of wheels.

(5) Since the rotational speed of the cutting motor can be changed arbitrarily, the ball firing interval can be set arbitrarily.

(6) Since the distance between the ball inlet and the pair of wheels can be made as small as the radius of the cutting blade, the time from cutting out to firing the ball can be shortened.

(7) The cutting blades cut out the balls one by one and send the cut balls directly to the firing wheel, so it is not possible to cut out the balls and send the balls to the firing wheel as in the conventional method. There is no need to use a separate mechanism for feeding and feeding, the number of parts can be reduced, the structure can be simplified, costs can be reduced, and the occurrence of failures can be reduced.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing one embodiment of the present invention, and FIG.
3 and 3 are explanatory diagrams of essential parts of the present invention, respectively. 1: Launcher body, 2: Launch tube, 3: Wheel insertion hole, 4: Ball inlet, 5: Hose, 6: Ball, 7: Hose joint, 8: Check plate, 9,
9: Upper and lower wheels, 10, 10: Upper and lower drive motors, 11: Shaft, 12: Set screw, 1
3: Ball cutting device, 14: Notch, 15:
Notch, 16: Cutting motor mounting plate, 17: Cutting motor, 18: Rotating shaft, 19: Set screw, 2
0: Feather, 21: Cut-out feather.

Claims (1)

[Claims] 1. In an aligned state, the balls are dropped into the launch tube from the ball inlet of the launch tube via a hose, and the balls that have fallen into the launch tube are pushed between a pair of opposing wheels via a ball cutting device and fired. In an automatic ball throwing device, the ball enters the launching barrel through a horizontally long slit formed in the launching barrel, which rotates in a direction perpendicular to the rotational direction of the pair of wheels, and the ball falls into the launching barrel from the ball inlet. A cutting blade that also serves as a feeder and is provided with a plurality of radial blades with an interval that accommodates one ball, and is provided so as to directly feed the balls one by one between the wheels, and the cutting blade is rotated at an arbitrary rotational speed. An automatic ball throwing device characterized by comprising a cutting motor capable of