Abstract: An ink chamber pressure enhancing control device, which includes a valve block mounted in the barrel of a writing instrument above an ink chamber, a cap axially movably mounted in the valve block above a valve port in the valve block, the cap having an air inlet, a piston supported on a spring member above the ink chamber in the barrel, wherein the piston is forced upwards by the spring member to close the valve port, enabling an air chamber to be formed within the cap and the valve block above the valve port, and from the air inlet at the cap and the valve port is forced into the ink chamber in the writing instrument when the cap is depressed.

Abstract: A pen cap for closing on a ball-point pen to prevent ink leakage, the pen cap including a cap body, a sealing cap covered on the cap body, and a ball valve mounted inside the cap body within the sealing cap and moved between inside ribs in the cap body and inside ribs in the sealing cap. Closing the pen cap on the pen causes excessive air to pass through an air passage formed by gaps among the inside ribs to the outside of the pen cap via an exhaust hole on the sealing cap, and the air passage is closed when the writing tip of the pen is engaged into a tapered hole on one cylindrical rod projecting from the ball valve.

Abstract: A writing apparatus which includes a pen holder holding an ink, a pen socket fastened to an open end of the pen holder and holding a sponge and an absorptive writing tip, an ink feeding valve assembly mounted in the pen holder and adapted to feed the ink to the sponge and the absorptive writing tip, and a steel ball movable in the ink inside the pen holder, the steel ball being movable by the pressure of the ink to close off a tapered rear opening on the ink feeding valve assembly and to stop the ink from passing to the inside of the ink feeding valve assembly when the pen holder is held in a writing position, and the steel ball being movable away from the tapered rear opening on the ink feeding valve assembly for permitting the ink to pass from the pen holder to the inside of the ink feeding valve assembly when the pen holder is placed in a horizontal position.

Abstract: A disc holder assembly including front and back cartridges defining flat outer surfaces of the assembly and one or more intermediate cartridges detachably and pivotably secured to the front and back cartridges or to each other to permit the insertion into or removal from each intermediate cartridge of a floppy diskette or compact disc when the assembly is pivoted into an open position forming a cylindrical sector.