3610223 is referenced by 59 patents and cites 3 patents.

A tennis ball launcher described wherein one ball at a time is selected from a hopper containing a supply of balls and positioned in a ball feed mechanism on a pair of spaced parallel supports. A mounted rotatable cylinder through which the balls pass from the hopper to the ball feed assembly has a spiral selector fixedly connected thereto. The selector extends into the hopper. The ball feed assembly is mounted independently of the rotatable cylinder and is vertically adjustable. A spring-loaded striker is released from a cocked position and passes between the parallel supports to impact the ball and propel the ball from the launcher. The striker is moved to a cocked position by a striker trigger assembly having a trigger actuator which engages a pin on the striker to move the trigger to a cocked position where the striker is released by the trigger actuator being cammed out of contact with the pin.

Title
Automatically operated spring-type projectile projecting device
Application Number
05/015,752
Publication Number
3610223
Application Date
March 2, 1970
Publication Date
October 5, 1971
Inventor
Green Wallace V
IPC
F41b 07/00
A63B 47/00
A63B 69/40
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