Pressure control device

A pressure control device installed inside an ink reservoir. The ink reservoir further includes a pressure regulator. The pressure control device at least includes a nozzle stand, a plugging block and a spring-loaded structure. The nozzle stand is attached to the bottom wall of the ink reservoir. The nozzle stand further includes a nozzle hole for linking up the interior of the ink reservoir with the exterior. The nozzle stand has a groove near the upper end of the nozzle. The plugging block is placed inside the groove for partitioning the interior of the ink reservoir from the exterior. The spring-loaded structure has a first section and a second section that connect with each other. The first section presses against the outer edge of the plugging block with an elastic force. The pressure regulator pushes the second section and lifts the first section away from the outer edge of the plugging block. A limiting structure may also be installed somewhere crossing the path of movement of the spring-loaded structure so that the range of movement of the spring-loaded structure is confined.