4
object electromagnetically. The threshold voltage value ought to be between 1.2 to 2.5V.
5. Set the output voltage slightly over the detected threshold so that the object can barely stick to the iron core.
Do not apply voltage exceeding DC 4V (maximum input voltage) to BRU.
Do not apply voltage well over the abovementioned threshold voltage value. Otherwise, electromagnetic
attraction generated by BRU will be too intense and residual magnetic flux will remain in the coil, due to
which BRU will release the free-falling object (plastic ball) delayed than theoretically expected.
How to use “Ball Launcher”:
Fig. 7 Ball launcher
Barrel is equipped with an actuator located on the inside of the barrel. In synchronization with triggering and releasing the
spring firing pin, designed to cut off a power supply to the coil of Ball Release Unit (BRU) to release a ball.
1. Grasp the knob of a Spring Firing Pin (SFP) , slowly take SFP from the barrel (
①
), and then, latch SFP at one of its four
equally spaced shallow cuts (grooves) (
②
) to determine the magnitude of launching the ball (see Fig. 8).
2. Attach a “Free-falling Object” beneath BRU in such a way that the small steel part of the ball surface directly contacts
with the iron core of BRU.
3. Put a “Projectile” in the barrel.
4. When pressing the trigger button of the ball launcher to release the spring firing pin, synchronously, power supply to the
coil of BRU will be cut off. Thus, the “Free-falling Object” will also be released simultaneously (see Fig. 8). As a result, the
projectile and the object will collide with each other.
Built-in lead wires (Red & Black, one each)
Barrel
Supporting rod (for adjusting firing angle)
Trigger / Stopper Button
Spring Firing Pin
