Abstract: A pressing device for a pen having a spring, a center stick engaging the spring and a nib part. The pressing device comprises a penholder having a guide slot, a movable tube having an outwardly projecting engaging piece that extends through the guide slot, a bounce device, a press or push cap, and a clipping part. The clipping part has a pen clip provided with a clamping piece that engages the engaging piece when the nib part is extended outwardly from the penholder in a writting position. When the pen is being attached to an article such as a pocket, the clamping piece will touch the article such that the pen clip is urged to move outward. As a result, the clamping piece will disengage the engaging piece. The engaging piece will move upward along the guide slot causing the spring to be stretched pressing the center stick upward such that the nib part will be received in the penholder.

Abstract: A pressing device for a pen and the pen further comprises a spring, and a center stick fitting with the spring and having a nib part. The pressing device further comprises a penholder, a movable tube, a bounce device, a press cap, and a clipping part. While the clamping piece on the clipping part touches a clipped article, the pen clip is urged to move outward and the clamping piece disengages with the engaging piece. The engaging piece moves upward along the guide slot because of the stretching of the spring and the pressing of the center stick till the stop ring has pressed against the upper opening. Accordingly, the nib part of the center stick may be received in the penholder automatically.

Abstract: A press type mechanical pencil includes an upper barrel, a press device, a refill tube, an abutting rod, a clamp/release device and a lower barrel. An insert post of the clamp/release device has a top portion connected to the abutting rod which is centrally provided with a refill hole for passage of refills. A refill tube is disposed between the abutting rod and the press device. A storage tube has a tube chamber for receiving a plurality of refills, and an open end connected to a tube plug. The tube plug is adapted to guide the refills and for connection with the abutting rod. A neck hole therein provides passage for only one refill through the refill hole into the clamp/release device.

Abstract: An automatic bounce device for a center stick in a pen comprises a pen holder, a center stick, a restore resilient part, and a push part. A locating hole and an engaging hole is provided on the pen holder. The push part is composed of an upper cap and a lock key tube. The upper cap movably fits with an opening end on the pen holder and a clip extends from the upper cap. The clip has a projection corresponding to the locating hole. The key tube is sleeved in the opening end and extends out of the pen holder. A inverse elastic hook part with an engaging hook is provided on the lock key tube and the center stick is received in the key tube. When the lock key tube is pressed, the engaging hook is moved away the engaging hole and slides into the locating hole to expose the nib on the center stick.

Abstract: A mold assembly for injection molding including a female mold having a first pair of opposite inside walls and a second pair of opposite inside walls disposed at four sides and defining a trapezoidal cavitys two trapezoidal locating plates respectively fastened to the first pair of opposite inside walls inside the female mold, and defining two symmetrical pairs of sliding ways within the female mold at different elevations between the trapezoidal locating plates and the second pair of opposite inside walls, and a mold set fitting the trapezoidal cavity of the mold set, the female mold consisting of a left mold half and a right mold half detachably abutted together, each mold half having two sliding tongues at different elevations and slidably fitted into the sliding ways.