Automatic tennis ball supply device

Abstract

An automatic tennis ball supply device, includes: a spring for transmitting the power via its elasticity; a first shaft which is joined to part 'b' which is the first part of a steel band of the spring; a handle for winding the spring; a first gear which rotates in the same direction as the first shaft; a second gear which rotates to the left when the wound spring runs down; a latch for disengaging the first and second gears from each other when the spring is wound, and for engaging the first and second gears with each other when the wound spring runs down; a third gear which rotates to the right, when the second gear rotates to the left; a second shaft which rotates in the same direction as the rotating third gear; a rotative speed control unit for controlling a rotative speed of the second shaft; a ball pick up unit for picking up and conveying one of the plural tennis balls in a container; a ball guide unit for guiding the tennis ball to outside. The automatic tennis ball supply device of the present invention, is given the power generated by the spring which is wound and then runs down, and thus picks up the plural tennis balls in the container one by one, before supplying the ball to the user, for user's tennis posture practice. Therefore, it is convenient to automatically supply the balls, instead of other people's throwing the balls to the user directly.