Abstract: An input pen is capable of being held in any one of input pen holding parts, respectively having different shapes, of various personal digital assistants. The input pen has a barrel, and stopping members fitted in opposite end parts of a metal tube. An elastic member is placed between the stopping members so as to push the stopping members outwardly. The metal tube is fitted in openings formed in the barrel. When the input pen is inserted into an input pen holding part of the personal digital assistant, the stopping members, properly projecting exteriorly through the openings of the barrel, are pressed against an inner surface of the input pen holding part. Thus, the input pen will not move even if there is a space between the barrel and the inner surface of the input pen holding part.

Abstract: A pen cylinder has at its front end a front input member made of a synthetic resin and at its rear end a rear input member made of a soft elastic material such as rubber. When performing an input operation onto a hard panel or an input operation of fine letters, an accurate input is achieved by using the front input member of synthetic resin provided on the front end of the pen cylinder. When performing input onto a soft panel or pointing input, an input free from damage to the panel is achieved by using the rear input member composed of soft elastic material.

Abstract: An input pen is capable of being held in any one of input pen holding parts (212A) respectively having different shapes of various personal digital assistants (212). The input pen has a barrel (201), and stopping members (209) fitted in the opposite end parts of the metal tube (208). An elastic member (210) is placed between the stopping members (209) so as to push the stopping members (209) outward. The metal tube (208) is fitted in openings (207A) formed in the barrel (201). When the input pen is inserted in an input pen holding part (212A) of the personal digital assistant (212), the stopping members (209) properly projecting outside through the openings (207A) of the barrel (201) are pressed against the inner surface of the input pen holding part (212A). Thus, the input pen will not move even if there is a space between the barrel (201) and the inner surface of the input pen holding part (212A).

Abstract: A input pen for a portable information processing terminal device with an input tip (12) biased axially forward by pressure applied thereto by a return spring (13). The pressure applied to the input tip (12) is optionally adjustable. A front barrel 10 is detachably attached to a front portion of a barrel (1). The input tip (12) is axially slidably inserted in the front barrel 10. The return spring 13 extended in the front barrel (10) applies pressure to the input tip (12) so as to bias the input tip (12) forward.

Abstract: A writing instrument with an input member for pressure-sensitive handwriting at one end, and a removable writing pen on the opposite end of a cylindrical body. A single cap of a diameter smaller than that of the cylindrical body may cover either the writing pen or the input member. The diameter of the cap is smaller that the diameter of the cylindrical body to lessen the chance of it being inadvertently dislodged.

Abstract: In a mechanical pencil, a tubular lead reservoir is connected to the rearward end of a lead chuck. A cylindrical weight is fitted slidably around the lead reservoir and is adapted to strike against the chuck to open the same to allow forward feed of the lead when a forward shake is applied to the pen barrel. In order to prevent forward feed of the lead as a result of unintended forward shake while carrying the pencil, a slider disposed rearwardly of the lead reservoir has a radially outwardly extending engagement projection which is adapted to slidably engage either a longitudinal guide slot in the pen barrel or a lateral slot circumferentially and rearwardly extending in the pen barrel. When the engagement projection is in engagement with the lateral slot, the chuck is caused to take an advanced position in which the chuck is open so that a forward stroke cannot feed the lead forward.