Electropneumatic paintball gun

An electropneumatic paintball gun is any of a class of markers that utilizes a pneumatic solenoid to actuate the hammer's movement.

History and Basic Operation

The origin of the electropneumatic paintball gun is the subject of a (warning: biased viewpoint in link) , but is generally acknowledged to have happened more or less simultaneously with the introduction of 's Angel V6 and ' Shocker, both in 1996.

Ignoring minor differences (WDP used a single, five-port solenoid, whereas the Shocker used the slightly less elegant solution of two separate solenoids, one for each movement), the two guns used the same operating principles. A trigger pull was translated into a microswitch activation, interpreted by a fire control PCB, and resulted in the solenoid(s) being switched to their hammer-forward configuration for a period of time known as the "dwell", after which the solenoid(s) were reset to rest position. In the process of moving the hammer forward, the chambered paintball was pushed past ball detents (intended to prevent the ball from rolling out of the barrel), and a cup seal was opened at the end of the hammer's throw, allowing air from the pressure chamber to flow through the bolt and onto the paintball.

The Backlash

The increased availability and use of these markers also coalesced a movement that had already been chafing at the technology advances of paintball. These players desired a return to the days of pump markers, ten-paintball clips, and 12-gram CO₂ "powerlets". The movement became that which we know today as "Stock-Class Paintball".

The Necessities of Very Fast Guns

The Angel and the Shocker exacerbated a fundamental problem that had been brewing in the sport—as guns got quieter, with less vibration and kick, the vibration that used to keep paintballs from jamming in the hopper feedneck went away. The solution was a move to motorized loaders, most notably the ViewLoader Revolution, which used a paddle to agitate the balls whenever an infrared beam in the feedneck became uninterrupted.

However, the reality of gravity set in, and it was obvious that to satisfy the appetites of the modern marker, the loader manufacturers were going to need to force the paintballs down the feedneck faster than mere gravity would allow. On modern guns, you'll see ViewLoader's eVLution, Odyssey's Halo, and the Q-Loader system doing just that, feeding at rates of up to one hundred balls per second.

Ball Detection Systems

(or, The Necessities of Very Fast Guns, pt. 2)

Two main ball-detection systems were created to ensure that a ball is present in the chamber when the user pulls the trigger. These systems were needed because, even as the loaders fed paint ever-faster into the guns, so too did the guns develop shorter firing cycles and more responsive electronics. Descriptions of the two BDS's and their subtypes follow:

Infrared Eye

Makes use of an infrared emitter and receiver to detect the presense of a ball.

Reflective

Detects whether a ball is present based on amount of emitted light reflected back to a sensor.

Break-Beam

Detects whether a ball is present based on whether or not a ball in the feed tube blocks a beam from reaching a receiver on the opposite side.

Weight Sensor

Detects presence of a ball based on force applied to a rod within the at the base of the chamber, which converts that force to an electrical signal via a piezoelectric "pad".

COPS/COPS2

Sensi

External Links

has an extensive tutorial on how the modern Angel paintball marker works.